Jurassic mountain building and Mesozoic-Cenozoic geodynamic evolution of the Northern Calcareous Alps as proven in the Berchtesgaden Alps (Germany)

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1 Facies (2011) 57: DOI /s ORIGINAL ARTICLE Jurassic mountain building and Mesozoic-Cenozoic geodynamic evolution of the Northern Calcareous Alps as proven in the Berchtesgaden Alps (Germany) Sigrid Missoni Hans-Jürgen Gawlick Received: 5 February 2010 / Accepted: 27 July 2010 / Published online: 25 August 2010 Springer-Verlag 2010 Abstract New data from the Berchtesgaden Alps result in a reconstruction of the Mesozoic-Cenozoic geodynamic history of the Northern Calcareous Alps. The closure of the western part of the Neotethys Ocean started in the late Early Jurassic and is evidenced by the onset of thick clayrich sediments in the outer shelf area (=Hallstatt realm). The Middle to early Late Jurassic contraction is documented by the migration of trench-like basins formed in front of a propagating thrust belt. Due to ophiolite obduction, these basins propagated from the outer shelf area, forming there the Bajocian to Oxfordian Hallstatt Mélange, to the Hauptdolomit/Dachstein platform area, where the Oxfordian Rofan and Tauglboden Mélanges were formed. The basins were separated by nappe fronts forming structural highs. This scenario mirrors syn-orogenic erosion and deposition in an evolving thrust belt. Active basin formation and nappe thrusting ended around the Oxfordian/Kimmeridgian boundary, which was followed by the onset of carbonate platforms on structural highs prograding towards the former basins in latest Oxfordian to Early Tithonian time. UnderWlled basins remained between the platforms. Rapid deepening around the Early/Late Tithonian boundary was induced by extension due to mountain uplift and resulted in the reconwguration of the platforms and basins related to normal and probably strike-slip faults. Erosion of the uplifted nappe stack including obducted ophiolites caused Wnal drowning and demise of the platforms in the Berriasian. The remaining Early Cretaceous basins were S. Missoni (&) H.-J. Gawlick Department for Applied Geosciences and Geophysics: Prospection and Applied Sedimentology, University of Leoben, Peter-Tunner-Str. 5, 8700 Leoben, Austria s.missoni@daad-alumni.de H.-J. Gawlick hans-juergen.gawlick@mu-leoben.at Wlled up with molasse sediments including siliciclastics until Aptian. Around the Early/Late Cretaceous boundary again extension and strike-slip movements started, followed by Eocene thrusting and Miocene strike-slip movements with block rotations. These younger tectonic movements destroyed the Triassic to Early Cretaceous palaeogeography and arranged the modern block conwguration. The described Jurassic to Early Cretaceous history corresponds with that of the Western Carpathians, the Dinarides, and the Albanides, where (1) age dating of the metamorphic soles prove late Early to Middle Jurassic inneroceanic thrusting followed by late Middle to early Late Jurassic ophiolite obduction, (2) Kimmeridgian to Tithonian shallow-water platforms formed on top of the obducted ophiolites, and (3) latest Jurassic to Early Cretaceous sediments show postorogenic character. Therefore, we correlate the Jurassic geodynamic evolution of the Northern Calcareous Alps with the closure of the western part of the Neotethys Ocean. Keywords Eastern Alps Neotethys Ocean Stratigraphy Carbonates Radiolarites Mélange Subduction Introduction The aim of this paper is to outline the Mesozoic-Cenozoic geodynamic history of the Northern Calcareous Alps and a contribution to the question: strike-slip tectonics (e.g., Channell et al. 1990, 1992; Frank and Schlager 2006) versus subduction-related tectonics in the Jurassic; the latter resulted in thrusting and formation of a nappe stack/thrust belt (Kimmeri(di)c orogeny of Sengör 1985a; Gawlick et al. 1999a). From the Berchtesgaden Alps we present:

2 138 Facies (2011) 57: (A) New data from the Berchtesgaden unit, which prove its palaeogeographic position in the Tirolic Hauptdolomit/ Dachstein carbonate platform realm rather than a palaeogeographic position as an isolated carbonate platform in the outer hemipelagic shelf area (Juvavic realm; Hallstatt Zone). (B) New data from the Trattberg Rise showing its evolution from an Oxfordian nappe front in an evolving thrust belt to a Kimmeridgian to Early Tithonian morphological high with a prograding shallow-water carbonate platform on top, and its Wnal Late Tithonian collapse due to extensional and probably strike-slip tectonics. (C) New data from the Hallstatt realm in Toarcian/Aalenian times to explain the late Early Jurassic extension in the inner parts of the Northern Calcareous Alps probably as a result of the onset of thrusting in the Neotethys Ocean to the east. NW-ward thrusting (in palaeogeographic coordinates) was responsible for the formation of a forebulge in the interior of the Austroalpine lower plate, e.g., in the Tirolic realm of the Northern Calcareous Alps. This contrasts the extension model, which considers late Early Jurassic extension as result due to the opening of the Penninic Ocean to the west (Eberli 1988; Ratschbacher et al. 2004). Contemporaneous inneroceanic thrusting is well dated in the Dinaridic/Albanide/Hellenide ophiolite zones (Karamata 2006). (D) New data on Middle to Late Jurassic trench-like basins, which prove a coarsening-upward trend in each basin and termination of sedimentation by the approach of huge slides, which can partly be interpreted as overthrust nappe relics. (E) New insights in the type area of the Sillenkopf Basin, which was interpreted as a radiolaritic trench-like basin (Missoni et al. 2001a; Gawlick and Frisch 2003) but in fact represents a deep-water starved basin like the Kimmeridgian Tauglboden Basin in between independent parts of the Plassen Carbonate Platform sensu lato. (F) New data from the type locality of the Early Cretaceous Rossfeld Formation, which show a lack of components from both the Hallstatt Zone as well as the Berchtesgaden unit. The Hallstatt outliers on top of the Rossfeld Formation are explained as southward-thrust elements of the Hallstatt Mélange during Miocene tectonic extrusion. (G) New data on the diagenetic and metamorphic overprint of the area including metamorphic slides in the nonmetamorphic Late Jurassic Hallstatt Mélange. This conwrms a Jurassic metamorphic overprint in the provenance area of the Hallstatt Limestone and Late Jurassic exhumation of the metamorphic rocks. Our results together with the known facts enable a more precise reconstruction of the Jurassic to Early Cretaceous tectonic evolution of the Northern Calcareous Alps. A comparison with the Western Carpathians, the Dinarides, or the Albanides show a homogenous picture for the sedimentological, facies and geodynamic evolution in Triassic to Early Cretaceous times along the Neotethys north-western margin. N S geographic directions refer to the present, caused by a complex rotation pattern of the Eastern Alps since Late Cretaceous (e.g., Haubold et al. 1999; Csontos and Vörös 2004; Thöny et al. 2006; Pueyo et al. 2007). NW SE directions refer to Triassic to Early Cretaceous palaeogeographic reconstructions. Juvavic and Tirolic nappes in the Berchtesgaden Alps: classical concept and historical alternatives The classic tectonic subdivision of the Northern Calcareous Alps (Figs. 1, 2) (in its fundamentals established by Haug 1906, later modiwcations by, e.g., Hahn 1913; Kober 1923; Spengler 1951; Plöchinger 1980; Tollmann 1985) dewned three nappe groups, from bottom to top: Bavaric, Tirolic, and Juvavic nappe group. This tectonic concept, established in the Berchtesgaden Alps and in the Salzkammergut area, was widely accepted. Later, a subdivision into three tectonic units ( Stockwerke sensu Lebling et al. 1935) was proposed for the Berchtesgaden Alps: the Tirolic unit ( Tirolische Einheit sensu Hahn 1913) at the base, overlain by the Lower Juvavic unit ( Tiefjuvavische Einheit sensu Kühnel 1929; Hallstatt nappes), and the Upper Juvavic unit ( Hochjuvavische Einheit sensu Kühnel 1929; Berchtesgaden nappe). According to this concept, the Tirolic unit in the north (Mt. Hochstaufen) should dip to the south, and the Tirolic unit in the south (Watzmann and Hochkalter massifs, Mt. Hoher Göll and Steinernes Meer massif) should dip to the north, thus forming a bowl-shaped structure under the rather Xat-lying Juvavic units (e.g., Ampferer 1936; Tollmann 1976b, 1985; Ganss and Grünfelder 1979; Risch 1993; Langenscheidt 1994; Braun 1998; modiwed by Dorner et al. 2009) (Figs. 2A, 22A). In the salt-mine of Hallein Medwenitsch (1962) subdivided the Lower Juvavic nappe into a Lower ( Untere Hallstätter Decke ) and an Upper Hallstatt nappe ( Obere Hallstätter Decke ). In this concept fragmentary blocks of Lower Juvavic Hallstatt Limestones (Tollmann 1976b) framed the Upper Juvavic Berchtesgaden nappe (Reiteralm, Lattengebirge and Untersberg massifs) (Fig. 2A). Pichler (1963) subdivided the Tirolic unit into two synclines: The today uplifted Rossfeld syncline in the south characterized by a thick Early Cretaceous succession with isolated fragments of the Lower Juvavic nappe on top, and the Dürrnberg- Berchtesgaden syncline in the north, surrounded by a

3 Facies (2011) 57: Fig. 1 Tectonic sketch map of the Eastern Alps and study area (after Tollmann 1977; Frisch and Gawlick 2003). GPU Graz Palaeozoic unit, GU Gurktal unit, GWZ Greywacke Zone, RFZ Rhenodanubian Flysch Zone continuous Lower Juvavic nappe layer with prominent Permian evaporites (e.g., Schweigl and Neubauer 1997a). Another tectonic concept, which takes into account synsedimentary fracturing in Triassic limestones and the relevance of Jurassic breccias, was drawn by Fischer (1965). He suggested movements along the Torrener-Lammer fault zone in Triassic and, mainly, in Jurassic times, before the Upper Austroalpine nappe complex was sheared ov from its basement in Early Cretaceous (pre-gosauic) times. He postulated that the Juvavic thrust sheets (Berchtesgaden Schubmasse ) of the area represented submarine slide blocks from the so-called Pongau Swell ( Pongauer Schwelle ) in Neocomian times. In an alternative concept evaporites, subsumed as Alpine Haselgebirge (Permian salt-claystone succession; Ha- selgebirge Mélange according to Spötl et al. 1998), acted as a ductile paste and motor of gravitational tectonics. Gravitational tectonics in the Juvavic units should have started in the Oxfordian (e.g., Tollmann 1981, 1987; Mandl 1982; Lein 1985, 1987a) or Late Tithonian (Plöchinger 1974, 1976, 1984) and should be responsible for Late Jurassic to Early Cretaceous sliding of Alpine Haselgebirge and Hallstatt Limestone successions towards the north. According to these models (summarized in, e.g., Tollmann 1987; Lein 1987a), sliding began with signiwcant radiolaritic sedimentation in the Oxfordian when troughs with marine sedimentation were arranged along the median longitudinal axis of the Northern Calcareous Alps (Diersche 1980). In contrast to the Salzkammergut region, where material from the south (Hallstatt material) and the north (local material) should have Wlled up the Oxfordian radiolarite basin (e.g., Tollmann 1981, 1987; Mandl 1982), the radiolarite basin in the Salzburg/Berchtesgaden area was subdivided into two parts by the intermediate Steinplatte-Adnet-Trattberg Rise: the Schwendt-Glasenbach Basin to the north and the Berchtesgaden-Kühroint Basin to the south (Diersche 1980). The Schwendt-Glasenbach Basin received blocks and mass- Xow deposits from the Trattberg Rise, e.g., in the Osterhorn Mts. (Tauglboden Breccia; Schlager and Schlager 1969, 1973) or in the Unken syncline (Schwarzbergklamm breccia; Garrison and Fischer 1969). According to Diersche (1980), the southern Kühroint-Berchtesgaden Basin in the central Berchtesgaden Alps was surrounded by submarine ridges forming the source areas for the slide masses. Mainly based on ammonite stratigraphy (summarized in Diersche 1980), the onset of radiolarite sedimentation was estimated as Oxfordian. Hence, the Kühroint-Berchtesgaden Basin was Wlled up by deep-water cherty limestones to radiolarites with intercalated breccias and turbidites of the Tauglboden Formation in sense of Diersche (1980). Slump folds are a characteristic feature in these sediments (e.g., Garrison and Fischer 1969; Schlager and Schlager 1973; Diersche 1980;

4 140 Facies (2011) 57: Tollmann 1987; Braun 1998). The formation of the generally asymmetric radiolarite basins was attributed to extensional tectonics (e.g., Schlager and Schlager 1973; Diersche 1980; Vecsei et al. 1989). Another group of authors attributed basin formation and breccia mobilization to strike-slip tectonics (e.g., Wächter 1987; Frank and Schlager 2006; Ortner et al pars). Triassic palaeogeography: controversies The reconstruction of the Triassic palaeogeography, i.e., the facies zones of the Hauptdolomit/Dachstein carbonate platform and its transition to the hemipelagic Hallstatt Zone, plays a crucial role in the diverent tectonic concepts (Fig. 2B, C, E, F). Various models exist, which diver in the

5 Facies (2011) 57: Fig. 2 Controversial tectonic models based on diverent facies concepts for the Northern Calcareous Alps. A Classical nappe subdivision with the Tirolic nappes at the base, overlain by the Lower (subdivided in a lower and an upper Hallstatt nappe) and Upper Juvavic nappes (after Tollmann 1985). B Facies reconstruction of the Late Triassic shelf with several long lasting hemipelagic Hallstatt facies channels in between shallow-water carbonate areals (after Tollmann 1985; based on Zankl 1967). C Schematic cross section through the Late Triassic shelf conwguration (after Tollmann 1987; Mandl 2000). T 2 Middle Triassic, T 3 Late Triassic. D Recent block conwguration in the central Northern Calcareous Alps (Frisch and Gawlick 2003). E Palaeogeographic reconstruction and facies distribution of the northwestern Neotethys realm in Late Triassic time (palaeogeographic position of Austroalpine realm modiwed after Krystyn and Lein in Haas et al. 1995). See text for explanation. IAZ Iberia-Adria-Zone; AAT future Austroalpine-Adria-transform; TTT future Tisza-Tatratransform; TMT future Tisza-Moesia-transform. AA Austroalpine; BI Bihor; BR Brianconnais; BU Bükk; C Csovar; Co Corsica; DI Dinarids; DO Dolomites; DR Drau Range; HA Hallstatt; JU Juvavicum; JL Julian Alps; ME Meliaticum; MK Mecsec; MO Moma unit; MP Moesian platform; P Pilis-Buda; R Rudabanyaicum; SI Silicicum; SL Slovenian trough; SM Serbo-Macedonian unit; TA Tatricum; TO Tornaicum; TR Transdanubian Range; VA Vascau unit; WC central West Carpathians. F Schematic cross section through the north-western passive margin facing the Neotethys Ocean (Austroalpine realm) in Late Triassic time showing a typical passive continental margin facies distribution (after Gawlick and Frisch 2003). For other reconstructions of the western (Neo)Tethyan realm see e.g., Frisch (1980), Sengör (1985a, b), Channell et al. (1990), Dercourt et al. (1986, 1993), Marcoux and Baud (1996), Channell and Kozur (1997), StampXi and Borel (2002), and StampXi and Kozur (2006) palaeogeographic restoration of the Triassic facies zones in the north-western Neotethys realm and in the assumed positions of the Austroalpine basement complexes. In the single shelf model all facies belts have been arranged in a characteristic shore parallel fashion (Fig. 2F) with a gradual transition from the outer shallow-water carbonate platform (Dachstein Limestone reefs) to the hemipelagic Hallstatt Zone (e.g., Lein 1985; Plöchinger 1995; Gawlick et al. 1999a; Gawlick and Frisch 2003; Gawlick et al. 2007a). Another reconstruction shows a broad transitional area from platform to hemipelagic conditions with isolated shallow-water platforms within the Hallstatt realm ( Juvavic platforms, Fig. 2C) (e.g., Schlager 1967; Zankl 1967, 1971; Tollmann 1985, 1987; Krystyn and Lein in Haas et al. 1995; Mandl 2000). In these concepts, the position of the later Neotethys suture zone is situated south of the Northern Calcareous Alps. In the dual shelf model (Neubauer 1994; Schweigl and Neubauer 1997a) the current tectonic position of the Hallstatt Zone between the Tirolic and the Upper Juvavic nappes suggests a position of the oceanic suture within the Northern Calcareous Alps ( Meliata-Hallstatt Ocean ; compare also e.g., Kozur 1991; Schweigl and Neubauer 1997a; Neubauer et al. 2000; StampXi et al. 2001; StampXi and Kozur 2006). The various models are still under discussion and contrast diverent tectonic interpretations of the Alpine/Carpathian mountain belt. The Berchtesgaden Alps, and especially the original conwguration of the Hauptdolomit/Dachstein carbonate platform and its transition to the hemipelagic Hallstatt facies realm, are crucial for understanding the palinspastic position of the Juvavic realm and Jurassic tectonic movements. DiVerent reconstructions of the Triassic shelf con- Wguration result in diverent models for Jurassic tectonics (e.g., Gawlick et al. 1999a; Frank and Schlager 2006). Schlager (1967) and Zankl (1967) proposed that Hallstatt facies belts formed autochthonous channels within the carbonate platform as shown by lateral interwngering with the Dachstein Limestone reef facies. In reef slope Wssures (Mt. Hohes Brett) cephalopods may be trapped and embedded in red Hallstatt limestones (Zankl 1971). In this model the faunal elements and the lateral interwngering of the Hallstatt facies with reefal sediments suggested a deposition on a distal slope of the shelf (see discussion in Rieche 1971). According to this model, the Hallstatt depositional basins were characterized by permanent vertical tectonic movements and corresponding changes in relief, which resulted in thick accumulation of reefal sediments and signiwcantly less subsiding basins with low sedimentation rates (Schwarzacher 1948; Zankl 1967, 1971). The broad hemipelagic troughs in between shallow-water platforms should be connected by channels (Fig. 2B, C) ( Berchtesgaden- Hallstätter Kanal sensu Mojsisovics 1903; discussion in Tollmann 1985). In this model the later Berchtesgaden nappe formed an isolated Triassic platform in the Hallstatt realm. The platform should be separated by intensely deformed Permo-Scythian evaporites and red beds as well as Triassic basinal sediments (Frank and Schlager 2006; Mandl: plate 8 in Pestal et al. 2009). Palaeogeographically the platform was located north of the southern Hallstattchannel ( Südkanal or Euhallstätter Kanal sensu Tollmann 1981, 1985; Zankl 1967) and south of the middle Hallstatt-channel (Fig. 2B, C). The southern channel should be the depositional area of the Hallstatt Limestone successions and all northern channels for the Pötschen Limestone/Dolomite successions. One key point in this discussion is the palaeogeographic position of the variegated and grey facies of the Hallstatt Limestone successions ( Hallstätter Buntkalk or Hallstätter Salzberg facies on one hand and Pötschen/Zlambach facies with shallow-water debris on the other; Lein 1985, 1987b; Gawlick et al. 1999a). The Late Anisian to Early Jurassic sedimentary succession (Figs. 3, 4) represented an open marine, distal periplatform setting on the Triassic European continental margin facing the Neotethys Ocean (=Meliata Ocean according to several authors) (Fig. 2E). The variegated Hallstatt facies represents the oceanward belt on this margin, giving way to siliceous limestones and radiolarites towards the Neotethys Ocean (=Meliata facies; Fig. 2F).

6 142 Facies (2011) 57: Fig. 3 Stratigraphic table of Triassic formations and tectonic events in the Northern Calcareous Alps (modiwed after Gawlick and Frisch 2003). The main detachment horizons are shown because they were used during Jurassic nappe stacking and disintegration of the sequence in the course of mélange formation There are no coarser than silt-sized siliciclastic or carbonate platform components in the Hallstatt and Pötschen Limestone sensu stricto sections. The fauna (mostly radiolarians, conodonts, Wlaments, ammonoids, no shallow-water elements) is characteristic for a hemipelagic/deep-benthic setting. The carbonate mud of the Hallstatt Limestone successions was most likely derived from the Triassic carbonate platforms (Wetterstein, Hauptdolomit/Dachstein platforms). In times of rapid progradation of these platforms only the Zlambach facies zone (Fig. 2F) received reefal detritus, which is missing in the Hallstatt Salzberg facies and in the Meliata facies zones (Fig. 3). In this oceanward facies belts only an increase of carbonate mud deposition can be measured (Gawlick and Böhm 2000). In deep-water settings (like the Hallstatt Zone) adjacent to large, Xat-topped carbonate platforms, the shedding of carbonate sand and mud during sea-level highstands has a major control on sediment accumulation rates (Schlager et al. 1994). Highstand shedding during short-order sealevel oscillations in a proximal periplatform setting of the Sevatian Dachstein carbonate platform was investigated by Reijmer and Everaas (1991). They found increased bed thicknesses during intervals of input from the platform interior, assumed to represent sea-level highstands (Schlager et al. 1994). The highstand shedding concept predicts:

7 Facies (2011) 57: Fig. 4 Stratigraphic table and main tectonic events of the Jurassic to Early Cretaceous period (after Gawlick et al. 2009a)

8 144 Facies (2011) 57: (a) Condensed sedimentation during relative sea-level lowstands, when the platform is emerged; (b) moderate accumulation during transgression, when most platform-produced carbonate is stored on the platform; and (c) highest sedimentation rates during the highstand phase, when the platform starts to prograde and exports excess sediment (Coniglio and Dix 1992). These processes work in concert with possibly varying current activities leading to erosion and omission during lowstands (Martire 1992). Using these predictions for the interpretation of the sedimentary environment of the Hallstatt Salzberg facies with relatively stable hemipelagic conditions for at least 40 Ma, the existence of large intermediate shallow-water carbonate platforms is quite unrealistic (Gawlick and Böhm 2000), despite the fact, that the Zlambach facies zone, which is situated closer to the shallow-water area, mirrors exactly the platform progradation phases (Krystyn and Lein 1996; Gawlick and Böhm 2000; Krystyn et al. 2009) by the input of shallow-water debris. For the Hallstatt Salzberg facies Gawlick and Böhm (2000) concluded that sedimentation rates of the Hallstatt Limestone successions are also strongly inxuenced by platform export, controlled by sea-level Xuctuations and platform aggradation or progradation. Middle and Late Norian tectonic inxuence slightly modiwed this model by the formation of new topographic highs in the Hallstatt realm (e.g., Lein 1981) as well as new deep basinal areas Wlled with mass-xow deposits and large slide blocks (Fig. 3; Pedata Basins, e.g., Lein 1985; Gawlick 1998). Strike-slip movements were recently discussed as reason for this Norian tectonic event (Missoni et al. 2008). However, the widely used model of topographic highs during the entire Middle and Late Triassic with condensed red Hallstatt Limestone successions on top (e.g., Mandl 2000; Hornung 2007; Pestal et al. 2009) must be replaced by a model, in which sea-level changes and carbonate export from adjacent shallow-water areas control sedimentation rates in the distal shelf areas (Gawlick and Böhm 2000). Jurassic tectonics: controversies Independent from diverent interpretations of the conwguration of the Triassic shelf the discussion on the general geodynamic regime in Middle to Late Jurassic times is also highly controversial. Mélanges deposited in newly formed basins contain blocks and slides up to nappe size. The blocks occur in a turbiditic radiolarite-rich matrix of Bajocian to Oxfordian age and consist of radiolarites as well as pelagic/hemipelagic and shallow-water limestones, all of Triassic to Early Jurassic age but of diverent palaeogeographic provenance, partly mixed. Two contrasting interpretations are currently under discussion: 1. Elongate basins formed in a strike-slip tectonic regime (Frank and Schlager 2006), and 2. trench-like basins formed in a propagating thrust belt (Gawlick et al. 1999a). In the Wrst model Jurassic strike-slip tectonics were followed by Early Cretaceous nappe stacking with active trench formation. The Early Cretaceous (Rossfeld) basin Wlls were terminated by overthrusting nappes. In the second model nappe thrusting and the formation of trench-like basins started in the Middle Jurassic and ended in the Late Jurassic, followed by mountain uplift with an extensional collapse in the latest Jurassic. This resulted in a reconwguration of the basins as well as the build-up and destruction of the newly formed Late Jurassic carbonate platforms. These basins were partly Wlled up in the late Early Cretaceous. Due to multiphase tectonic overprint of thrusts and highangle faults, an interpretation on the basis of structural kinematic analysis of thrusts and faults is diycult. But it allows in combination with an analysis of the basin Wlls the reconstruction of the geodynamic regime. In a transpressive strike-slip model the trend of grain size and bed thickness in the basinal deposits should be irregular, because source areas, transport routes and depocentres shift during strikeslip faulting (e.g., Steel and Gloppen 1980; Cemen et al. 1985; Frank and Schlager 2006). In trenches in front of advancing nappes a coarsening-upward trend should be observed and sedimentation terminated by the emplacement of a nappe (Hsü 1982). Therefore, in order to get precise information about the tectonic regime, we analysed the basin Wll sediments deposited in relation to the tectonic movements. Stratigraphic results: Tirolic realm For all investigated localities see Fig. 5. Berchtesgaden nappe The sedimentary succession of the Berchtesgaden nappe (Figs. 3, 4, 6, 21, 22) started in the Early Triassic with brownish-grey Werfen siliciclastics, overlain by greenishgrey carbonates of the Werfen Formation (Böse 1898; Barth 1968; Risch 1993), followed by brownish limestones and dolomites with evaporites (Rauhwackes of the Reichenhall Formation) in the southern part, and by partly thick successions of clay-rich evaporites of the Reichenhall Formation in the northern part. In the southern part of the Berchtesgaden nappe the Reichenhall Formation is

9 Facies (2011) 57: Fig. 5 Topographic sketch map with localities mentioned in the text. Inset indicates the study area in Germany and Austria. The Berchtesgaden Alps are part of the Northern Calcareous Alps (NCA) described by Lebling et al. (1935) from the northern part of Mt. Grünstein and in a brooklet near the Engert-Alm (Schwerd et al. 1998). To the north, the Reichenhall Formation occurs as greenish-grey-blue leached saline clay in the Gschirrkopf area (Risch 1993) and is drilled in the saltdeposit of Bad Reichenhall (Schauberger and Zankl 1976). The Reichenhall Formation is partly the detachment horizon for the Eocene Berchtesgaden nappe, especially in its northern parts, where the original sedimentary succession is partly incomplete. In the southern part the Reichenhall Formation is followed by Anisian carbonate ramp deposits of the Gutenstein and Steinalm Formations. The Steinalm Formation is overlain by a drowning sequence of hemipelagic sediments of the ReiXing Formation. Shallow-water do-lomites of the Steinalm Formation, hemipelagic ReiXing Dolomite and shallow-water dolomites of the Wetterstein carbonate platform were formerly subsumed under the term Ramsau Dolomite (e.g., Risch 1993; Schwerd et al. 1998). The light-grey Ramsau Dolomite (Böse 1895) is problematic and complex in its lithological features with a mixture of facial and stratigraphical orders (Summesberger 1966), due to its assumed continuous dolomitic shallowmarine facies from the Late Anisian to Early Carnian (e.g., Risch 1993). The Anisian shallow-water carbonates are mostly overlain by dolomitized hemipelagic grey carbonates of the ReiXing Formation which are mostly rich in

10 146 Facies (2011) 57: Fig. 6 Comparison of sedimentary sequences of the Eocene Berchtesgaden nappe, Steinernes Meer analogue, Watzmann-Hochkalter analogue, and the Kehlstein-Göll-Freieck analogue. The typical Steinernes Meer section at the southern rim of Steinernes Meer massif belongs to the Upper Tirolic nappe (Fig. 2D) and contains the type locality (Clessinsperre section) of the Steinalm Formation (Pia 1930): in the topmost parts of the shallow-water Steinalm carbonates occur a rich algal Xora with, e.g., Physoporella dissita Gümbel, Physoporella pauciforata Gümbel, Teutloporella peniculiformis Ott (Pia 1930; crinoids, Wlaments and chert. Drowning of the Steinalm carbonate ramp in the Late Anisian is proven in the Gschirrkopf area and in the Weiherbach brooklet by conodont taxa (Figs. 5, 6). The age range of the ReiXing Formation is Illyrian to Langobardian (Missoni et al. 2001b; Missoni 2003). On Mt. Kienberg (Fig. 5) at the western margin of the Berchtesgaden unit the Steinalm Formation is overlain by reddish to grey bedded hemipelagic limestones (Häusler and Berg 1980), dated by conodonts as Late Anisian (Fig. 6). Upsection follow ReiXing Dolomites up to the Ladinian. Characteristic conodonts, which would document a Late Langobardian or Early Carnian progradation of the Wetterstein carbonate platform, were not found in these dolomites. Due to these stratigraphic and facies Wagner 1970; Tollmann 1976a), overlain by bedded hemipelagic limestones with a rich ammonoid fauna (Broili 1927; Schnetzer 1934) including Paraceratites trinodus Mojsisovics (Schnetzer 1934; Wagner 1970). This indicates a lowermost Illyrian age in sense of Krystyn et al. (2004) (ReiXing Limestone in sense of Pia 1930). In all sections the microfacies changes from shallow-water carbonates to sediments with pelagic inxuence containing crinoids, Wlaments and partly Wne-grained shallow-water debris, and Wnally to hemipelagic sediments with Wlaments and radiolarians characteristics, Mt. Kienberg does not belong to the Hallstatt Mélange, in this area named Saalach Zone (Fig. 2), as it was assumed by Häusler and Berg (1980). The sedimentary succession is similar to the succession in the Maria Gern area and therefore belongs to the Berchtesgaden nappe (Fig. 6). Due to strong dolomitization, the stratigraphic overturn from the Ladinian ReiXing Formation (dolomite) to the reefal Wetterstein Dolomite is not exactly dateable in the Berchtesgaden nappe. Upsection limestones and dolomites of the Wetterstein carbonate platform follow (Mt. Hirscheck, Mt. Grünstein, Mt. Untersberg), overlain by proximal Julian Cidaris beds containing the conodont taxon Metapolygnathus polygnathiformis (Budurov and Stefanov) on the eastern edge of Mt. Untersberg. Oolithic sandstones are

11 Facies (2011) 57: also common in the late Early Carnian Raibl Formation (Risch 1993; Prey 1969). Due to intense deformation in this level, the typical gradual decrease of siliciclastic input upsection, as elsewhere in the central Northern Calcareous Alps (Grottenthaler 1978), is not preserved. The?Late Carnian dolomitic ramp deposit of the Opponitz Formation (Mt. Hirscheck, Mt. Untersberg; see Risch 1993 for Late Carnian occurrences) is followed by Norian shallow-water Dachstein Limestone in the northern part of the Berchtesgaden nappe. The upper part of the lagoonal Dachstein Limestone section is eroded (Froh 1976; Risch 1993). Rhaetian to Early Jurassic sediments are only proven as small and rare Wssure Wllings (Risch 1993; Oetken 1991). Steinernes Meer analogue The typical Middle Triassic section of the Steinernes Meer massif can be drawn as follows: above of the Early Anisian Gutenstein Formation follow Middle Anisian shallowwater carbonates of the Steinalm Formation (Pia 1923). The drowning of the Steinalm carbonate ramp took place in the Late Pelsonian (L. Krystyn and R. Lein, pers. comm.), followed by Late Anisian to Ladinian ReiXing Limestone (section Clessinsperre; Fig. 6). The facies changes from shallow-water carbonates to hemipelagic sediments with crinoids, Wlaments and Wne-grained shallow-water debris, then to dark-grey, laminated organism-rich sediments with marls, and later to dark-grey nodular limestones. The overlying bedded sequence (ReiXing Limestone in sense of Pia 1923; compare Tollmann 1976a) contains characteristic conodont taxa near the base: Paragondolella pseudolonga (Kovacs, Kozur and Mietto) and Paragondolella excelsa (Mosher) indicate a (Middle) Illyrian to lowermost Fassanian age (Fig. 6). The microfacies show hemipelagic sediments with Wlaments and radiolarians. In the Late Ladinian the Wetterstein carbonate platform started to prograde with a shallowing-upward cycle. The youngest sediments are lagoonal deposits. Early Carnian Raibl beds follow upsection. Late Carnian bedded dolomites are followed by the Norian-Rhaetian lagoonal Dachstein Limestone (Fischer 1964, 1975; Enos and Samankassou 1988; Schwarzacher 2005). North of the main plateau of the Steinernes Meer massif and south of the Torrener-Joch Fault zone Jurassic sequences are preserved (compare Fig. 21A). Well-dated Late Hettangian to Aalenian Hierlatz and Adnet Limestone successions (e.g., Jurgan 1969; Schöll and Wendt 1971) are rarely followed by red condensed limestones of the Klaus Formation (Diersche 1980) of Bajocian-Bathonian age. Upsection follow coarse-grained mass-xow deposits of the Early Callovian Klauskogelbach Member, topped by Callovian-Oxfordian radiolarites and a complex radiolaritic deep-water basin to shallow-water carbonate platform pattern of Kimmeridgian age, described in detail below. Watzmann-Hochkalter analogue The Watzmann-Hochkalter massif (Fig. 6) is separated from the Steinernes Meer massif by the Miocene Eisgraben Fault zone (Decker et al. 1994). In this fault zone highly deformed early Middle Triassic dolomites of the Gutenstein and Steinalm formations occur (e.g., Bodechtel et al. 1984). According to Haber et al. (1935), the sequence north-west of the Eisgraben Fault zone (compare Fig. 21A) starts with slightly northward dipping dolomites of the Wetterstein carbonate platform, overlain by thin remnants of the Raibl Formation. Upsection follow Late Carnian dolomites and Norian to Rhaetian lagoonal Dachstein Limestone with intercalated Early Rhaetian Kössen beds (Missoni et al. 2005). Therefore, the Watzmann-Hochkalter massif represents the southernmost rim of the Kössen Basin in sense of Golebiowski (1991), followed by a rapid progradation of the Rhaetian Dachstein Limestone, in its lower part with reefal patches. Strongly condensed Early to Middle Jurassic Adnet Limestone successions in the Herrenroint-Kühroint area (e.g., Haber et al. 1935; Diersche 1980) are followed by the Callovian to Oxfordian Strubberg Formation. Trattberg Rise The Trattberg Rise in the inner Northern Calcareous Alps separated the Upper and the Lower Tirolic nappe (Frisch and Gawlick 2003). This topographic high (e.g., Schlager 1953; Diersche 1980; Plöchinger 1983, 1990) shed its material into the adjacent Tauglboden Basin to the north (Schlager and Schlager 1973; Diersche 1980; Vecsei et al. 1989; Gawlick et al. 1999a, b). In the Berchtesgaden Alps it is represented in the Kehlstein-Göll-Freieck Mountains and Mt. Untersberg. The rise formed the nappe front of the Upper Tirolic nappe since the Early Oxfordian. Stratigraphy and facies of remnants of the sedimentary succession suggest that this high had its position within the Triassic lagoonal Dachstein Limestone facies zone. Late Triassic to Middle Jurassic sediments were eroded, mobilized as blocks and slides, and redeposited in the Tauglboden Basin. In the Berchtesgaden Alps, sediment redeposition from the Trattberg Rise (Mt. Mannlköpfe, Mt. Hoher Göll) into the Tauglboden Basin ended with the prograding Late Jurassic shallow-water Plassen Carbonate Platform sensu stricto (Mt. Untersberg). Around the Early/ Late Tithonian boundary the original topography of this rise and overlying Plassen Carbonate Platform on its southern limb (Mt. Untersberg Fugger 1907a) was destroyed along northward dipping normal faults (e.g., Mt. Kehlstein). The Plassen Carbonate Platform sensu stricto became again an area of erosion, and a new steep reef rim facing the Tauglboden Basin was formed (Schlagintweit and Gawlick 2007; Gawlick and Schlagintweit 2009).

12 148 Facies (2011) 57: Fig. 7 Late Triassic sedimentary succession of the Trattberg Rise, Mt. Hohes Freieck east of Mt. Hoher Göll. Insets show typical microfacies of the Late Norian to Rhaetian succession. The Rhaetian reef faces the Kössen Basin to the north. This clearly documents the palaeogeographic position of the area near the southern rim of the Kössen Basin (Fig. 3) and far away from the Dachstein Limestone reef zone facing the Hallstatt Zone Kehlstein-Göll-Freieck analogue The sedimentary succession of the Kehlstein-Göll-Freieck massif (Fig. 6) starts with bedded lagoonal Dachstein Limestone of Norian age (Zankl 1969). Several occurrences of Kössen beds from Mt. Freieck to Mt. Hoher Göll (Wegerer and Gawlick 1999) are dated by conodonts (Braun 1998; Missoni 2003) or ostracod taxa (Bolz 1971) as Early Rhaetian. Reefal to lagoonal limestones of Rhaetian age marked the end of the Triassic shallow-water carbonate sedimentation (Fig. 7). The most complete Jurassic sequence is preserved in the overturned limb of the Kehlstein anticline (Fig. 6). Whereas the Early Jurassic sediments are fairly well investigated and dated by ammonites (e.g., Fischer 1969; Braun 1998), the age of the overlying Jurassic radiolaritic sequences was a matter of speculation (Diersche 1980; Braun 1998). The sedimentary record of this overturned radiolarite sequence starts with Early Callovian grey to reddish cherty, partly laminated limestones to radiolarites. Further upsection occur Early Oxfordian reddish cherty limestones to radiolarites of the Fludergraben Member (Fig. 4). This section overthrusts the Early to?middle Oxfordian grey cherty laminated limestones with mass-xow deposits (Tauglboden Formation Missoni 2003), described in detail below. The inverted Triassic to Early Oxfordian sequence on top of the Early/?Middle Oxfordian Tauglboden Formation documents Early/Middle Oxfordian folding and thrusting of the Mt. Kehlstein, as part of the Trattberg Rise, over the Tauglboden Basin ( overthrusting : Böse 1898; Kühnel 1925; synsedimentary tectonics of the Dürreckberg fold with an inverted anticline : Otholt 1987). The normal limb of the anticline showed mainly incomplete successions (e.g., Plöchinger 1952, 1955; Braun 1998) with some remnants of Early Jurassic sediments (Zankl 1969). On top of Mt. Kehlstein the deeply eroded ramp anticline of Rhaetian lagoonal Dachstein Limestone (Schlagintweit et al. 2002) is transgressively overlain by mass-xow deposits (Barmstein Limestone) of the Plassen Carbonate Platform sensu stricto (Fig. 8) with intercalated hemipelagic limestones of late Early to Late Tithonian age, and later by uniform Late Tithonian/Early Berriasian deepwater sediments of the Oberalm Formation. This succession is dated by shallow-water organisms deriving from the Plassen Carbonate Platform sensu stricto to the south: Dasycladales (e.g., sample Ber 101/1b) Clypeina jurassica (Favre and Richards), Clypeina parasolkani Farinacci and Radoicic; foraminifer Cladocoropsis mirabilis Felix, and incertae sedis Tubiphytes sp. Late Tithonian in the higher hemipelagic sequences is dated by calpionellids (Braun 1998). The Oberalm Formation and Barmstein Limestone sealed the Rhaetian lagoonal Dachstein Limestone of Mt. Kehlstein. Untersberg analogue On the western edge of Mt. Untersberg, Late Triassic to Late Jurassic sediments prevail in a highly deformed zone, which is also interpreted as frontal part of the Trattberg Rise, the analogue to the overturned Trattberg anticlines of

13 Facies (2011) 57: Fig. 8 Erosive surface of the Rhaetian lagoonal Dachstein Limestone in sedimentary contact with the Late Jurassic shallow-water carbonates of the Plassen Carbonate Platform sensu stricto. Trattberg Rise, Mt. Kehlstein (sample Ber 101/9). C clast of Rhaetian lagoonal Dachstein Limestone Mt. Kehlstein (photo in Braun 1998: Wg. 61) or north of Mt. Loser in the central Salzkammergut area (Missoni and Gawlick 2010). On Mt. Untersberg, a sequence of Late Triassic lagoonal Dachstein Limestone is preserved followed by Early Jurassic limestones of the Adnet Group and Early to Middle Oxfordian radiolaritic sediments of the Ruhpolding Radiolarite Group (Fig. 9). In all other regions of the Berchtesgaden unit (Mt. Untersberg, Lattengebirge and Reiteralm massifs) the section is mostly eroded down to a level of the Norian lagoonal Dachstein Limestone, overlain by Late Cretaceous Gosau Group sediments above an erosional surface (e.g., Herm 1962; Risch 1993). This long lasting emersion of the Dachstein Limestone may have been the reason for its strong recrystallization, which Wnds its expression in the term Dachstein Limestone of the Reiteralm type (e.g., Hahn 1913; Froh 1976). Therefore, we interpret also this part as deeply eroded continuation of the Trattberg Rise. A large area in the northern part of Mt. Untersberg is covered by reefal limestones of the Late Jurassic Plassen Formation (e.g., Fugger 1907a, b; Dya 1992). The Plassen Formation partly lies transgressively on top of the Norian Dachstein Limestone, but mostly occurs in a graben-like position together with Gosau sediments incorporated in the fault zones (Prey 1969 and unpublished data; compare Figs. 21A and 22). Stratigraphic results: Hallstatt realm Toarcian to Aalenian Birkenfeld Formation Fig. 9 Selected radiolarians of the Williriedellum dierschei subzone of the Zhamoidellum ovum zone (Early to Middle Oxfordian) (Gawlick et al. 2009a) from the western edge of Mt. Untersberg near Wolfschwang (sample Ber 23/1): 1 Parahsuum sp. sensu S Matsuoka, 2 Stichocapsa robusta Matsuoka, 3 Theocapsomma cordis Kocher, 4 Unuma gordus Hull, 5 Eucyrtidiellum unumaense (Yao), 6 Eucyrtidiellum nodosum Wakita, 7 Eucyrtidiellum ptyctum (Riedel and SanWlippo), 8 Stylocapsa spiralis Matsuoka, 9 Dictyomitrella kamoensis Mizutani and Kido, 10 Archaeodictyomitra amabilis Aita, 11 Theocapsomma cucurbiformis Baumgartner, 12 Sphaerostylus lanceola (Parona) The Hallstatt Zone is only known from blocks in the Hallstatt Mélange. From these blocks a complete sedimentary succession with Anisian Steinalm Formation, a Pelsonian to Sevatian grey and reddish hemipelagic Hallstatt Limestone succession, Rhaetian Zlambach Formation, and Hettangian to Sinemurian bedded spicula- and radiolaria-rich cherty limestones of the Dürrnberg Formation (Gawlick et al. 2001a) is reconstructable (Figs. 3, 4). In the Pliensbachian dark-grey thin-bedded cherty limestones with marls occur (O Dogherty and Gawlick 2008). The sedimentation changed in Toarcian times to a thick-bedded succession of dark-grey marly to siliceous limestones with shales, dewned here as Birkenfeld Formation. These sediments are mapped

14 150 Facies (2011) 57: Fig. 10 Selected Late Toarcian to Aalenian radiolarians (=Hexasaturnalis hexagonus subzone of the Hsuum exiguum zone; Gawlick et al. 2009a) of the salt-mine Berchtesgaden. 1 Hsuum altile Hori and Otsuka sample Ber 73/3, 2 Hsuum exiguum Yeh and Cheng sample Ber 73/6b, 3 Hexasaturnalis hexagonus (Yao) sample Ber 73/6b, 4 Parvicingula nanoconica Hori and Otsuka sample Ber 73/3, 5 Parahsuum simplum Yao sample 73/3c, 6 Parvicingula gigantocornis Kishida and Hisada sample Ber 73/4, 7 Elodium cameroni Carter sample Ber 73/3c, 8 Paronaella grahamensis Carter sample Ber 73/1, 9 Pseudopoulpus acutipodium Takemura sample Ber 73/3d, 10 Parasaturnalis diplocyclis (Yao) sample Ber 73/3c, 11 Ares sp. A Baumgartner et al. sample Ber 73/3, 12 Orbiculiforma cf. radiata De Wever sample Ber 73/3d, 13 Triactoma jakobsae Carter sample Ber 73/3, 14 Perseus hachimanensis Takemura and Nakaseko sample Ber 73/3d, 15 Napora nipponica Takemura sample Ber 73/3, 16 Zartus imlayi Pessagno and Blome sample Ber 73/3c, 17 Linaresia rifensis (El Kadiri) sample Ber 73/3. (Species are common in all samples) in the Birkenfeld gallery of the salt-mine Berchtesgaden, dated as Toarcian by ammonites (Gümbel 1888). Well-preserved radiolarians of this formation precised the age as Late Toarcian to Aalenian by characteristic taxa (Fig. 10). Birkenfeld Formation History: Wrst description as Birkenfeld Einlagerung by Gümbel (1888) in the salt-mine Berchtesgaden (for history see Kellerbauer 1996). Type area and section: type locality is the Birkenfeld gallery in the salt-mine Berchtesgaden. Derivation of name: after the Birkenfeld Schachtricht (gallery) in the salt-mine Berchtesgaden. Lithology: dark-grey cherty marls to cherty limestones (Fig. 11). Deep-water sediments. Chronostratigraphic age: Toarcian to Aalenian. Thickness: several tens of metres; probably up to 100 m. Underlying and overlying formations: Dürrnberg Formation in the footwall. Overlying formations are unknown. Geographic distribution: actually only known from the type locality; a possible other occurrence is in the Backhaus gallery in the salt-mine Hallstatt. Stratigraphic results: Middle to Late Jurassic trenchlike to underwlled foreland basins In the Alpine-Carpathian domain the sedimentation pattern diachronously changed from calcareous to siliceous in the Middle Jurassic. The tectonic regime also changed, which has been explained in diverent ways (e.g., Tollmann 1985, 1987; Gawlick et al. 1999a; Faupl and Wagreich 2000; Neubauer et al. 2000; Frank and Schlager 2006). A characteristic new feature is the formation of trench-like rapidly subsiding radiolaritic basins with deposition of up to 2,000- m-thick sequences in their southern, oceanward parts (Gawlick 1996). In contrast, their northern, continentward edges are characterized by uplift and condensed sedimentation or erosion. The derivation of the resedimented components divers. In a southern basin group the material is shed either from the Triassic to Early Jurassic distal, hemipelagic to pelagic continental margin (Hallstatt and Meliata Zones) or the Zlambach facies and the Dachstein reef rim zone, whereas in a northern basin group the material derived from the Triassic to Middle Jurassic lagoonal area (Dachstein and Hauptdolomit facies zones) (Fig. 4, compare Figs. 23, 24).

15 Facies (2011) 57: Fig. 11 Characteristic microfacies of the Birkenfeld Formation in the salt-mine Berchtesgaden, Birkenfeld gallery (Hallstatt Mélange). A Filament-, spicula- and radiolaria-rich marly wacke- to packstone, slightly bioturbated, partly rich in organic material. Sample Ber 73/1. Width of photo: 1.4 cm. B MagniWcation of A. Most spicula and radiolaria are recrystallized, but some occur as quartz. Slightly bioturbated. Each reconstruction of the Jurassic tectonic movements depends on detailed studies on the components and the stratigraphy of the siliceous matrix sediments. The following diverent carbonate-clastic, radiolaritic (wild)xysch-like sequences with characteristic Middle to Late Jurassic sedimentation in the Northern Calcareous Alps can be distinguished at the moment (Gawlick et al. 2009a) (Fig. 4): (A) Florianikogel Basin with the Florianikogel Formation. Its Middle Jurassic matrix (?Bajocian to Callovian) contains material from the Hallstatt Salzberg and Meliata facies belts as well as volcanogenic greywacke layers (Neubauer et al. 2007) in a slightly metamorphosed radiolaritic argillaceous matrix. The existence of this basin is proven in the south-eastern and central Northern Calcareous Alps (Mandl and Ondrejicková 1991, 1993; Kozur and Mostler 1992; Gawlick 1993) and the similar Meliata Formation in the Western Carpathians (Kozur 1991; Kozur and Mock 1997; Mock et al. 1998). (B) Sandlingalm Basin group with the Sandlingalm Formation (Gawlick et al. 2007a). This Early Callovian to Width of photo: 0.25 cm. C Radiolaria-rich marly wacke- to packstone, Wlaments are common, partly rich in organic material. Sample Ber 73/3c. Width of photo: 0.5 cm. D Radiolaria-rich marly wackestone, Wlaments are common, slightly bioturbated. Sample Ber 73/6b. Width of photo: 0.5 cm Late Oxfordian basin contains only material from the Hallstatt Salzberg facies zone and Pötschen Limestone, which mainly derived from the transitional area to the Meliata Zone (Fig. 4). Resedimentation started in the type area of Mt. Sandling in the Early Callovian. Similar Hallstatt Mélanges in the Salzkammergut area are Bajocian-Bathonian in age (Gawlick et al. 2009a). (C) Lammer Basin with the Strubberg Formation (Early Callovian to Middle Oxfordian; e.g., Gawlick and Frisch 2003). This basin contains mainly material from the Zlambach facies zone and the marginal Dachstein Limestone reefs. Resedimentation started in the Late Callovian respectively around the Callovian/Oxfordian boundary and therefore later than in the Sandlingalm Basin. The basal part of the Strubberg Formation (Klauskogelbach Member; Early Callovian) contains mass-xow deposits with components of the lagoonal Dachstein Limestone facies zone (Suzuki et al. 2001). These resediments of local derivation prove the onset of nappe thrusting in this basin in Early Callovian times (Gawlick et al. 2009a).

16 152 Facies (2011) 57: (D) Tauglboden Basin with the Tauglboden Formation (Schlager and Schlager 1969, 1973; Early Oxfordian to Early Tithonian: Huckriede 1971; Gawlick and Frisch 2003). The Wrst phase of resedimentation in this basin started in the Early Oxfordian (Gawlick et al. 2007a) with local material (lagoonal Dachstein Limestone facies zone) and ended around the Middle/Late Oxfordian boundary. After a period of tectonic quiescence and low sediment supply (latest Oxfordian to Early Tithonian) the second phase of intense resedimentation started slightly in Early Tithonian, increased around the Early/Late Tithonian boundary, had its climax in Late Tithonian, and lasted until the Berriasian. It occurred in an overall extensional regime (Schlagintweit and Gawlick 2007). Characteristic is the change from mainly Triassic to Middle/Late Jurassic clasts in a shaly/ marly-siliceous matrix to clasts of Late Jurassic reefal sediments in a matrix of siliceous limestones of Late Tithonian to Middle Berriasian age (Steiger 1992; Gawlick et al. 2005). The carbonate clasts in the intercalated mass Xows derived from a contemporaneous shallow-water carbonate platform as well as from the older Late Jurassic shallow-water Plassen Carbonate Platform sensu stricto (Kimmeridgian to Berriasian) (Schlagintweit and Gawlick 2007; Gawlick and Schlagintweit 2009). (E) Rofan Basin with the Rofan breccia (Wähner 1903). Resedimentation started in the Late Oxfordian with material derived from the Hauptdolomit facies zone (e.g., Wähner 1903; Wächter 1987) and prevailed until the Oxfordian/Kimmeridgian boundary or Early Kimmeridgian. By that time the sedimentation changed to mostly carbonate detritus, derived from a carbonate platform to the south (Wolfgangsee Carbonate Platform Gawlick et al. 2007b, 2009a). (F) Another type of basin represents the Sillenkopf Basin with the Sillenkopf Formation (Kimmeridgian to?tithonian: Missoni et al. 2001a) with components of mixed palaeogeographic origin. The radiolarite basins A to E were formed in sequence from south to north prograding from the Meliata to the Hauptdolomit facies zone in the time span from the Bajocian to the Oxfordian/Kimmeridgian boundary. Basins A, partly B, and C were accreted and overthrust, basin B only partly. Basins D, E, F, and partly B existed in Kimmeridgian to early Early Tithonian times as remnant basins in between newly formed shallow-water carbonate platform areas of the Plassen Carbonate Platform sensu lato. Sandlingalm Basin: material from Hallstatt Salzberg facies zones Detailed studies in stratigraphy and facies of the former Lower Juvavic Hallstatt nappe in the Berchtesgaden Alps (e.g., v. Lipold 1854; Gümbel 1861; v. Mojsisovics 1868; Bittner 1882; Schlosser 1898; Waagen 1899; Fugger 1907a; Kühnel 1929; Krumbeck 1938; Plöchinger 1955, 1976; Tollmann and Kristan-Tollmann 1970; Rieche 1971; Braun 1998; Hornung and Brandner 2005) gave various tectonic interpretations of the Pelsonian to Sinemurian history of the hemipelagic to pelagic sedimentary blocks in Hallstatt Salzberg facies. Recent studies in the central Salzkammergut area resulted in the identiwcation of the Callovian to Oxfordian carbonate-clastic, radiolaritic basin-wll sequence of the Sandlingalm Formation in the Sandlingalm Basin. This formation contains blocks up to kilometre-size, which derived only from the Hallstatt Salzberg facies and the Meliata facies zones (including cherty Pötschen Limestone without reefal detritus), but lacks in both components from the Zlambach facies zone with shallow-water debris and the marginal Dachstein Limestone reef zone. This basin was formed relatively early and was probably situated south of the Tirolic nappe system in front of the advancing Hallstatt nappes. The Hallstatt nappe stack became completely eroded and is only preserved as components in the Middle to Late Jurassic radiolaritic (wild)xysch-like sequences within the southern Tirolic units. The sedimentary succession of the Sandlingalm Basin in the Berchtesgaden Alps (=Berchtesgaden-Hallein Hallstatt zone of, e.g., Tollmann 1985) is composed of Callovian- Oxfordian sediments with a radiolaritic matrix and various slide masses derived from the Hallstatt Salzberg facies zone. The matrix of this basin Wll consists of grey to reddish cherty limestones to radiolarites and siliceous shales; slump folds and slump deposits are common in the lower part of the succession. The Callovian-Oxfordian age of these sediments (e.g., sample Ber 13/7 from the Schönau area) is proven by following radiolarian taxa: Zhamoidellum ovum Dumitrica, Eucyrtidiellum unumaense (Yao), Eucyrtidiellum unumaense pustulatum Baumgartner, Hsuum maxwelli Pessagno, Archaeodictyomitra minoensis (Mizutani), Gongylothorax av. favosus Dumitrica, Striatojaponocapsa plicarum (Yao), Zhamoidellum ventricosum Dumitrica, Williriedellum dierschei Suzuki and Gawlick. The Sandlingalm Formation strikes from Antenbichl to the northern area of Schönau, and from there to the Dürrnberg area (compare Fig. 21A). The Sandlingalm Formation sensu stricto is overlain by salt deposits of the Haselgebirge

17 Facies (2011) 57: Mélange (e.g., Berchtesgaden and Hallein-Bad Dürrnberg salt-mines; compare Fig. 20). Resedimentation of Hallstatt blocks in this basin ended around the Oxfordian/ Kimmeridgian boundary or in the Early Kimmeridgian (Fig. 12) when the sedimentation of grey siliceous hemipelagic limestones started. These limestones belong to the basinal sequence aside the early Plassen Carbonate Platform sensu lato and were deposited on top of slide masses sealing the chaotic basin Wlls (compare Fig. 20). This situation mirrors the situations around Mt. Sandling or Mt. Plassen (Suzuki and Gawlick 2009) in the Salzkammergut area. Lammer Basin: material from Zlambach facies and Dachstein reef zones The westward continuation of the Lammer Basin in the Salzburg Calcareous Alps into the Berchtesgaden Alps has been proven by Missoni et al. (2001b, 2005), Gawlick et al. (2003), and Missoni (2003). The basin Wll in the type area (Gawlick 1996) and the Berchtesgaden Alps is composed of late Middle to early Late Jurassic deep-water shales to cherty matrix sediments intercalated with mass-xow deposits and kilometre-sized slides, dewned as Strubberg Formation (Cornelius and Plöchinger 1952) (Figs. 13, 14). In the Berchtesgaden Alps, in an early stage of sedimentation the basin was Wlled by slide blocks, which derived from the Zlambach facies zone. In a later stage the source area shifted to the Late Triassic reef rim; the component size of the matrix- to grain-supported mass-xow deposits and olistoliths in the basin showed a general coarseningupward trend (Figs. 13, 20). In the Krautkaser brooklet the sedimentation started in?late Callovian times with dark, partly manganese-rich, partly laminated argillaceous to cherty limestones and radiolarites. Most components of the polymict mass-xow deposits are small clasts from the distal Zlambach facies zone (limestones of the ReiXing and Pötschen Formations, partly with shallow-water detritus) with an age range from Late Pelsonian to Julian, resp. Lacian (Fig. 14A, B). Further upsection, in the Gschirrkopf area, slides and mass Xows bear clasts from a more proximal Zlambach facies zone than those in the Krautkaser brooklet. The slides mostly consist of dolomites of the Pötschen and Pedata Formations with an age range from Julian to Sevatian. In a later stage of sedimentation polymict breccias and mass-xow deposits contain millimetre- to centimetresized components of the proximal Zlambach facies zone in transition to the Late Triassic reef rim. In the Herrenroint- Kühroint area reef slope to forereef components occur rarely, whereas these components are numerous in the polymict breccias of the Hanselgraben brooklet (Fig. 14C). In the late stage of sedimentation the component size of the breccias and mass-xow deposits increased. In the Büchsenkopf Fig. 12 Selected Kimmeridgian radiolarians (sample Ber 5/11/1) of the Podocapsa amphitreptera zone (Gawlick et al. 2009a), and selected Tithonian radiolarians (sample Ber 71/1, RTW 30) from hemipelagic sediments which overlie the Sandlingalm Basin in the Berchtesgaden Alps. 1 Podocapsa cf. amphitreptera Foreman, 2 Angulobracchia cf. biordinalis Ozvoldova, 3 Podobursa cf. triacantha triacantha (Fischli), 4 Emiluvia chica Foreman, 5 Hsuum cf. brevicostatum (Ozvoldova), 6 Fultacapsa sphaerica (Ozvoldova), 7 Zhamoidellum ventricosum Dumitrica, 8 Eucyrtidiellum pyramis (Aita), 9 Archaeodictyomitra apiarium (Rüst), 10 Wrangellium puga (Schaaf), 11 Protunuma multicostatus (Heitzer), 12 Sphaerostylus lanceola (Parona), 13 Tetracapsa zweilii (Jud), 14 Hiscocapsa cf. uterculus (Parona), 15 Sphaerostylus squinaboli (Tan), 16 Zhamoidellum ovum Dumitrica. 1 to 6 from sample Ber 5/11/1 (Zauberwald). 7 to 11 from sample Ber 71/1 (Dürrnberg area). 12 to 16 from sample RTW 30 (Dürrnberg area) area, the basal part of the section contains polymict mass-xow deposits bearing various clasts derived from the Dachstein reef zone (Figs. 14D, 20). Further upsection metre-sized olistoliths and large slides occur, which derived from a fore slope facies of the Late Triassic reef rim (Lacian 1 to basal Early Jurassic) incorporated in laminated grey cherty matrix sediments of Early/Middle Oxfordian age (Fig. 13C).

18 154 Facies (2011) 57: Fig. 13 Late Triassic to late Middle Jurassic successions with clasts and slide blocks contained in the Strubberg Formation: A Mt. Hohes Brett, view from Mt. Jenner. B Mt. Jenner, view from the Büchsenkopf area. C Büchsenkopf area, view from the slope of Mt. Jenner. Component sizes show a general coarsening-upward trend from centimetre- (Büchsenkopf area) to kilometre-sized (Mt. Hohes Brett). Compare Fig. 14 Upsection follow several hundred metres to kilometresized slides with completely preserved sequences. Mt. Jenner represents a huge slide with a Late Carnian to Sevatian succession of the slope of the Dachstein reef rim, underlain by grey Late Callovian to Middle Oxfordian matrix sediments (Fig. 13B). The Callovian to Oxfordian age of the Strubberg Formation near the base of Mt. Jenner is proven by characteristic radiolarian taxa (sample Ber 54/10): Archaeodictyomitra amabilis Aita, Eucyrtidiellum unumaense dentatum Baumgartner, and Eucyrtidiellum unumaense unumaense (Yao), Gongylothorax av. favosus Dumitrica, Praezhamoidellum yaoi Kozur, Striatojaponocapsa conexa (Matsuoka), Striatojaponocapsa plicarum (Yao), Tricolocapsa sp. M sensu Baumgartner et al., Unuma gordus Hull, Williriedellum dierschei Suzuki and Gawlick, Williriedellum glomerulus (Chiari, Marcucci and Prela), and Williriedellum marcucciae Cortese. The reef block of Mt. Hohes Brett (Zankl 1969) terminated the carbonate-clastic, radiolaritic basin Wll of the Lammer Basin (Fig. 13A): the Late Triassic sedimentary succession of Mt. Hohes Brett, where Zankl (1971) manifested the interwngering of Hallstatt Limestone with reefal Dachstein Limestone, started in the?middle or Late Norian, as evidenced by the occurrence of conodont taxa:

19 Facies (2011) 57: Norigondolella steinbergensis (Mosher), and Neohindeodella sp. (samples Ber 86/1, Ber 86/9). Hemipelagic intercalations were dated as Sevatian with the conodont taxon Epigondolella bidenta Mosher (Otholt 1987; Braun 1998). The reef slope and reef sediments near the top of this mountain were sealed by crinoidal limestones (Donnerkogel Formation: Krystyn et al. 2009; Fig. 3), dated as Early Rhaetian with the conodont taxa Norigondolella steinbergensis (Mosher), Oncodella paucidentata (Mostler), and juvenile Misikella hernsteini (Mostler) (sample Ber 86/15). Hence, the age range of the forereef/reef Dachstein Limestone of Mt. Hohes Brett is?middle or Late Alaunian to Sevatian/Early Rhaetian. The interwngering of reddish to greyish hemipelagic limestones with shallow-water material (not Hallstatt Limestone) at the base of the succession results from a short-term transgression in context with Middle to Late Norian tectonic movements. This tectonic event is characterized by a transgression of the hemipelagic facies towards the Hauptdolomit/Dachstein carbonate platform followed by a rapid progradation of the Dachstein reefs towards the Hallstatt Zone. This scenario with a major transgression in the Alaunian 3 is, e.g., known from Mt. Hohe Wand (Krystyn and Lein 1996), Mt. Grimming (Böhm 1988), Lake Gosausee (Krystyn 1991), Mt. Gosaukamm (Schauer 2002; Krystyn et al. 2009), Mt. Hochkönig, and several other Dachstein reefs (L. Krystyn, pers. comm.; M. Schauer, pers. comm.). Also, the Early Rhaetian transgression with a backstepping of the Dachstein reefs is remarked in various Dachstein Limestone reefs in the Northern Calcareous Alps, e.g., Mt. Gosaukamm and Lake Gosausee (Schauer 2002; Krystyn et al. 2009). The model of (permanent) extension near the Dachstein reef rim towards the Hallstatt Zone (Zankl 1971) must be replaced by a model of Middle to Late Norian tectonic movements with the creation of new accommodation space and widespread transgression towards the platforms, followed by rapid progradation of the Dachstein reefs in Late Norian and the drowning/backstepping of the reefs during the Early Rhaetian transgression. Due to later tectonic movements, the basal Middle to early Late Triassic sedimentary succession of the Dachstein reef rim zone in the area of the Berchtesgaden Alps is not very well preserved. It is compared with the situation at Gollinger Schwarzenberg to the east (Gawlick and Gawlick 1999; Gawlick et al. 1999a). Reconstructions can only be done from diverent slices in the negative Xower structure of the Torrener-Joch Fault zone south of Mt. Hohes Brett (compare Figs. 3, 5, 21A): the Steinalm Formation is proven by the occurrence of the algae Physoporella pauciforata Gümbel (H. Zankl, pers. comm.), the ReiXing Formation is unproven, the Wetterstein Formation is indirectly proven by the dasycladale Poikiloporella duplicata Pia from the overlying Leckkogel Formation (Moussavi 1985). The Leckkogel Formation is followed by bedded cherty dolomites of the Waxeneck Formation on Mt. PfaVenkegel. Early Norian sediments are not preserved.?middle Alaunian to Early Rhaetian reef slope sediments are proven in a section north of Mt. PfaVenkegel to Mt. Hohes Brett (see above).?rhaetian Dachstein reefal limestone is indirectly proven by Hettangian Wssure Wllings (e.g., Zankl 1971). According to Braun (1998), Domerian to Late Toarcian Wssure Wlls of brown-greyish limestones with chert nodules and marly intercalations occur between Mt. Brettriedel and Mt. Großer Archenkopf. The Callovian to Middle Oxfordian age of the Strubberg Formation near the base of Mt. Hohes Brett is proven by characteristic radiolarian taxa in dark-grey radiolarites (sample Ber 8/3): Praezhamoidellum buekkense Kozur, Praezhamoidellum yaoi Kozur, Theocapsomma cf. cucurbiformis Baumgartner, Striatojaponocapsa conexa (Matsuoka), Striatojaponocapsa cf. plicarum (Yao), Tricolocapsa sp. M sensu Baumgartner et al., and Williriedellum marcucciae Cortese (Fig. 13A). Deep- or shallowwater sediments younger than Oxfordian are unknown in the Lammer Basin. In general, the sedimentary record of the Strubberg Formation in the Berchtesgaden Alps documents a shift of depocentres in the basin, from the accreted proximal Zlambach facies zone to the reef-margin of the Late Triassic carbonate platform facies (compare Figs. 23, 24). This is shown in two independent general coarseningupward trends (Figs. 13, 20). Tauglboden Basin: material from lagoonal Dachstein Limestone facies zone Remnants of the westward continuation of the Tauglboden Basin of the type area in the Osterhorn Mts. (Schlager and Schlager 1973) with components of the Late Triassic lagoonal Dachstein Limestone facies zone are preserved in the western Dürreckberg area (Gawlick et al. 2002) below a ramp anticline (compare Fig. 22B). There, the Tauglboden Formation is composed of Late Jurassic cherty matrix sediments with intercalated polymict breccias and mass-xow deposits derived from the Trattberg Rise to the south (Mt. Hoher Göll Mt. Kehlstein area; Fig. 21A). Components of rare Rhaetian lagoonal Dachstein Limestone occur together with clasts of the underlying Kössen Formation and of the dominating Early Jurassic grey hemipelagic carbonates of the Enzesfeld and Scheibelberg Formations and with Middle Jurassic grey radiolarites, typical erosional products of the Trattberg Rise (Fig. 15). Sediment redeposition in the Tauglboden Basin ended in the Berchtesgaden Alps in Oxfordian times, with the overthrust of the Trattberg Rise, described above (compare Fig. 24).

20 156 Facies (2011) 57: Fig. 14 Microfacies of the Strubberg Formation. Matrix and components of the diverent mass-xow deposits. A DiVerent grey limestone clasts of the Pötschen Formation reworked in a dark-grey cherty matrix with recrystallized radiolarians. Most clasts are hemipelagic limestones of Late Triassic age, some contain reefal detritus of the nearby Dachstein reef belt. Sample Ber 9/8/1, Unterer Krautkaser (valley). Width of photo: 1.4 cm. B Subangular clasts of the Middle Norian Pötschen Formation with Wne-grained shallow-water debris, which derive all from the Zlambach facies belt, in a cherty-marly matrix. Sample Ber 46/1b, Unterer Krautkaser (valley). Width of photo: 0.5 cm. C Polymictic breccia with clasts from the fore slope of the Dachstein reef belt beside crinoid-rich clasts. Sample Ber 69/9, Kühroint. Width of photo: 0.5 cm. D Clasts of allodapic limestones with reefal material and small reef clasts in a cherty-marly matrix. Sample Bü 14c, Büchsenkopf. Width of photo: 0.5 cm. Compare Fig. 20 Sillenkopf Basin: exotic material and local clasts In Late Oxfordian time (Auer et al. 2009) resp. around the Oxfordian/Kimmeridgian boundary the Plassen Carbonate Platform sensu lato started to form on diverent topographic highs: (a) on the Trattberg Rise (Plassen Carbonate Platform sensu stricto), (b) on the Brunnwinkl Rise (Wolfgangsee Carbonate Platform), and (c) on an unnamed rise on top of the Hallstatt imbricates to the south, where the Lärchberg Carbonate Platform was formed (Missoni et al. 2001a; Schlagintweit and Gawlick 2007; Gawlick et al. 2009a). During this time, ramps and other topographic ridges with shallow-water sediments of the Plassen Carbonate Platform sensu stricto to the north and the Lärchberg Carbonate Platform to the south formed the Xanks of the Sillenkopf Basin. The Lärchberg Carbonate Platform and the platform-basin transition are preserved in the southern parts of Mts. Steinernes Meer and north of Mt. Gerhardstein (Fig. 21A; unpublished data). The Sillenkopf Basin represents from the latest Oxfordian times a starved deep-water basin in between these carbonate platforms. The Sillenkopf Formation is composed of Late Jurassic cherty matrix sediments intercalated with mass-xow deposits with partly exotic components. The sedimentary record of the Sillenkopf Basin sensu stricto (=Sillenkopf Formation) started on top of mass Xows with several lagoonal and reefal Dachstein Limestone components up to kilometre-size (Klauskogelbach Member Fig. 4), overlain by Callovian to Oxfordian radiolarites and the Late Oxfordian reddish cherty limestones to radiolarites of the Gotzen Member (Fig. 4). In the Abwärtsgraben brooklet and in the type area of the Sillenköpfe the overlying, laminated cherty limestones to radiolarites and cherty marls of latest Oxfordian to Kimmeridgian age contain mass-xow deposits, bearing various, partly exotic clasts derived from mixed allochthonous origin (Missoni et al. 2001a): millimetre- to centimetre-sized, partly encrusted

21 Facies (2011) 57: components of the Middle and Late Triassic Zlambach facies zone, Late Triassic reefal Dachstein Limestone, Middle Jurassic Bositra-wackestones, resedimented and partly encrusted clasts of the Lärchberg Carbonate Platform (e.g., Mt. Gerhardstein), small coated saline clasts (most probably derived from the Alpine Haselgebirge: salty-clay mudstones and gypsum), and weakly metamorphosed material of phyllites and carbonate-cemented sandstones. Components of small resedimented grey radiolaritic clasts rarely occur together with clasts of carbonate-cemented sandstones (party with coating), heavy minerals (apatite, zircon, garnet, tourmaline, rutile, actinolite, chlorite; moreover a rare assemblage with amphibole, epidote, anastase, and chromium spinel of ophiolitic origin; a spectrum otherwise only known from the Early Cretaceous Schrambach and Rossfeld Formations P. Faupl, pers. comm.). The metamorphic clasts (epidote, garnet, quartz, and chlorite) prove the existence of a deeply eroded hinterland in the south, which may simply be the basement of the Northern Calcareous Alps. Zircon and quartz reveal their derivation from volcanic sources, as proven by cathodoluminescence (Missoni and Kuhlemann 2001). The source for this volcanic material is possibly an ophiolite nappe stack carrying an island arc (Gawlick et al. 2008). The ophiolites are proven by the occurrence of chromium spinel; the amphiboles derive most probably from the metamorphic soles between the stacked ophiolites. A similar breccia was found in a borehole in the saltmine Berchtesgaden (Fig. 16). Components show a mixture of older local (Tirolic facies) and exotic material. This breccia is mostly grain supported. Only in few samples the argillaceous-cherty matrix, partly rich in spicula, is visible. The age of these breccias is not exactly determinable. They are best comparable with the breccias on top of the saltmine Altaussee (Breunerberg horizon), which occur there in a Kimmeridgian position. This type of breccias occurs only in Hallstatt Mélange areas in connection with the Haselgebirge Mélange (Gawlick et al. 2010). In the Tauglboden Mélange such breccias are unknown and also not expected. The determination as Tauglboden breccia as made by Braun (1998) is now corrected (Fig. 16). However, Oxfordian to Early Tithonian volcanic ashes were also described in the Tauglboden Basin (Huckriede 1971; Diersche 1980; Gawlick et al. 1999b). Stratigraphic results: Early Cretaceous Rossfeld Basin In the Rossfeld Basin type area, which represents the westward continuation of the Tauglboden Basin north of the Trattberg Rise of Mt. Kehlstein, the sedimentation lasted until the?barremian (Tollmann 1985). Around the Early/ Late Tithonian boundary the sedimentation changed from the radiolaritic Tauglboden Formation to the Late Tithonian to Middle Berriasian hemipelagic limestones of the Oberalm Formation intercalated with slope breccias of the Barmstein Limestone (Gawlick et al. 2005). In the Late Berriasian (not Valanginian) a slight increase of Wnegrained siliciclastic material led to the sedimentation of the Schrambach Formation (Tollmann 1985; Rasser et al. 2003) as proven by the occurrence of the following coccolithophorid taxa in the Schrambachgraben type locality: Nannoconus steinmannii Kamptner, Retecapsa angustiforata Black, Rucinolithus wisei Thierstein, and Conusphaera mexicana Trejo (samples B 272, B 287). The change from hemipelagic carbonates to siliciclastically inxuenced siliceous carbonates and marls occurred contemporaneously with the drowning of the Plassen Carbonate Platform sensu stricto to the south (Gawlick and Schlagintweit 2006). The Rossfeld Formation overlies the Schrambach Formation and is characterized by a coarseningupward trend. In former interpretations the Rossfeld Basin was a newly formed Early Cretaceous Xysch basin in a migrating foredeep in front of advancing Juvavic nappes (Faupl and Tollmann 1979; Tollmann 1985; Faupl and Wagreich 2000; Neubauer et al. 2000; Frank and Schlager 2006). The sedimentation should have been terminated by the overthrust of these nappes, documented by the Hallstatt outliers on top of the Rossfeld Formation (Figs. 2A, 21A, 22). By this interpretation mass-xow deposits, intercalated in calcareous sandstones and cherty limestones of the upper Rossfeld Formation should contain the complete component spectrum of the arriving nappes (e.g., Pestal et al. 2009) as documented in the Jurassic basins. However, our results on the uninvestigated carbonate components in these mass Xows of the type locality show only diverent Late Jurassic to Early Cretaceous shallowwater clasts from the Plassen Carbonate Platform sensu stricto, their drowning sequence, the following Early Cretaceous basinal sediments, and contemporaneous shallow-water clasts derived from an unexplored source in the hinterland (Fig. 17) beside the already known siliciclastic, volcanic, and ophiolitic components (Pober and Faupl 1988; Faupl and Pober 1991; Schweigl and Neubauer 1997b; v. Eynatten et al. 1996; v. Eynatten and Gaupp 1999; Faupl and Wagreich 2000). Triassic-Jurassic components from the Hallstatt Zone (Hallstatt and Pötschen Limestones) or Triassic shallow-water carbonate components of the Upper Tirolic Berchtesgaden unit as well as components of the Alpine Haselgebirge are completely absent (Fig. 17).

22 158 Facies (2011) 57:

23 Facies (2011) 57: Fig. 15 Microfacies of the Late Triassic to late Middle Jurassic succession as reconstructed from mass-xow deposits of the Tauglboden Formation, Dürreckberg area. Triassic-Jurassic components are similar to those in mass-xow deposits in the Tauglboden area (Gawlick and Frisch 2003) or at the base of Mt. Höherstein Plateau (Gawlick et al. 2007a). Overthrusting red radiolarites can be correlated with the Early Oxfordian Fludergraben Member forming the base of the Tauglboden Formation. The following radiolarians restricted to the Late Callovian to Middle Oxfordian were determined (sample Ber 43/19); Williriedellum carpathicum to Williriedellum dierschei subzones of the Zhamoidellum ovum zone (Gawlick et al. 2009a): Archaeodictyomitra cf. minoensis (Mizutani), Archaeodictyomitra mitra Dumitrica, Gongylothorax favosus Dumitrica, Gongylothorax av. favosus Dumitrica, Tricolocapsa funatoensis (Aita), Striatojaponocapsa plicarum Yao, Williriedellum crystallinum Dumitrica, Williriedellum carpathicum Dumitrica, Zhamoidellum ovum Dumitrica. A Clast of dark-grey radiolarian packstone of the distal Strubberg-Formation. Sample Alpl 12 g. B Amalgamated radiolaritic matrix with a clast of the Middle Jurassic Klaus Formation. Sample Br 11 k. C Clast of spicula-rich radiolarian wackestone of the Early Jurassic Scheibelberg Formation. Sample Br 11a. D Clast of spicula- and crinoid-rich packstone of the Early Jurassic Enzesfeld Formation. Sample Br 11d. E Clast of backreef-near lagoonal Rhaetian Dachstein Limestone. Sample Br 11e. F Clast of Early Rhaetian Kössen limestone. Sample Alpl 12f. Width of all Wgures: 1.4 cm Diagenetic to metamorphic patterns The age of the diagenetic to metamorphic overprint of the Northern Calcareous Alps is controversially discussed (e.g., Gawlick et al. 1994a; Gawlick and Höpfer 1999; Frank and Schlager 2006). The Wrst metamorphic overprint was of Jurassic age ( Ma: Neubauer et al. 2007; compare Schuster et al. 2007), avected the southernmost nappes of the Northern Calcareous Alps, i.e., the Ultra-Tirolic unit in sense of Frisch and Gawlick (2003), and predated the nappe emplacement in the Late Jurassic (e.g., Gawlick et al. 1994a). These age data resemble those at the Meliata suture zone in the Western Carpathians (Dallmeyer et al. 2008). The second metamorphic cycle around Ma (Neubauer et al. 2007) avected the southern parts of the Northern Calcareous Alps after the emplacement of the Hallstatt blocks and slides in the radiolaritic basins, respectively after the formation of the Hallstatt Mélange zones (Gawlick 1997). This event can most probably be correlated with the increasing heat-xow due to the uplift of the accreted Juvavic units in the southernmost part of the Northern Calcareous Alps. Metamorphism during the Eo-Alpine orogeny with its peak around 100 Ma (» Ma) was of diverent degree and again avected the southern parts of the Northern Calcareous Alps and also large parts of the Austroalpine crystalline basement (Frank 1987; Frank and Schlager 2006). All these events resulted in a polyphase metamorphic history of the (southern) Northern Calcareous Alps (Gawlick et al. 1994a). Pelagic carbonates of Triassic age are widely distributed in the eastern and central Northern Calcareous Alps, which enables temperature determinations by the use of the Conodont Colour Alteration Index (CAI). For CAI determination (e.g., Epstein et al. 1977; Rejebian et al. 1987; Nöth 1991, 1998; Königshof 1992; Sudar and Kovacs 2006) we used conodonts of the Tirolic Triassic sedimentary successions as well as resedimented slides and pebbles in the Jurassic mélanges in order to recognize transported thermal overprint. This can be done when the matrix sediments show low or no thermal overprint. Hence, we determined the diagenetic to metamorphic overprint in the Berchtesgaden Alps, especially of the Berchtesgaden nappe and Hallstatt Mélange (former Juvavic nappes ), in order to: (a) Prove the derivation of the Hallstatt outliers of the Ahornbüchsenkopf and the Klingeckkopf, which top the Early Cretaceous Rossfeld Formation in the type area (Figs. 21A, 22B), (b) argue for the emplacement of the diverent blocks ( Euhallstätter Deckschollen ) in?barremian times, and (c) validate the existence of the Jurassic metamorphic overprint by determining the CAI in diverent blocks of the Hallstatt Mélange. A survey of all huge Hallstatt Limestone blocks and Jurassic mass-xow deposits of the Berchtesgaden Alps showed slightly contrasting CAI values with a complicated distribution pattern (Fig. 21B). This rexects the polyphase thermal history with a slight decrease of the diagenetic overprint from CAI in the southern part (southern rim of Steinernes Meer Mts.: Gawlick et al. 1994a) to CAI (southern area of Lammer valley: Gawlick 1997) to CAI 1.0 in the north, with CAI zones CAI and CAI in between (Fig. 21B). The CAI zones generally trend east west. The thermal overprint avected both blocks and matrix of the mélange. Therefore, it is younger than Late Kimmeridgian (»150 Ma), and (as known from other areas) also avected by the youngest thermal overprint with a peak around 100 Ma (Gawlick et al. 1994a). In the Gschirrkopf area, north of the CAI 1.0 zone, occur slightly higher values of CAI (1.0 )1.5. Also the Ahornbüchsenkopf and Klingeckkopf outliers on top of the Early Cretaceous Roßfeld area show the same CAI values of CAI (Fig. 21B). This documents clearly, that the Gschirrkopf area and the Hallstatt outliers on top of the Rossfeld Formation came to their present position after the youngest diagenetic overprint ( Ma). Metre- to tens of metres-sized Hallstatt Limestone and reefal Dachstein Limestone slides contained in the uppermost Sandlingalm Formation show high conodont alteration values of CAI 6.0 (Fig. 18). These early Late Triassic carbonate blocks were found north of the salt-mine Bad

24 160 Facies (2011) 57:

25 Facies (2011) 57: Fig. 16 Components of mass-xow deposits of the Sillenkopf Formation from boreholes, salt-mine Berchtesgaden. A Clast of Rhaetian lagoonal Dachstein Limestone (D) and of spicula- and radiolaria-rich cherty limestone of the Sinemurian Dürrnberg Formation (DF) (Gawlick et al. 2001a). Sample TB Width: 1.0 cm. B Radiolaria- and spicula-rich Kimmeridgian cherty limestone on left side represents higher part of Sillenkopf Basin Wll. Reddish Late Jurassic crinoidal limestone on right side represents typical sediment below the prograding Plassen Carbonate Platform. Sample TB Width: 1.0 cm. C Early Jurassic Hierlatz Limestone (HL), radiolaria-rich Norian Pötschen Limestone (PL), and Jurassic cherty limestone of the Dürrnberg Formation (DF) in argillaceous-cherty matrix. Sample TB Width: 1.4 cm. D Mixture of Rhaetian lagoonal Dachstein Limestone (D), probably Middle Jurassic Wlament limestone (FL), Late Triassic Pötschen Dolomite (PD), and a Late Jurassic onkoid (O). Sample TB Width: 1.4 cm. E Mixture of clasts of diverent Middle to Late Jurassic radiolarites (R), Triassic and Late Jurassic shallow-water carbonates, Pötschen Dolomite, recrystallized Alpine Haselgebirge (H). Sample TB Width: 1.4 cm. F Clasts of Sinemurian-Pliensbachian Adnet Formation with Involutina liassica Jones (AF), Dachstein Limestone (D), Late Jurassic Plassen Carbonate Platform sensu lato (PCP), most probably from the Lärchberg Carbonate Platform. Sample TB Width: 1.0 cm. G Matrix-supported mud Xow with reefal components of the Plassen Carbonate Platform sensu lato (PCP), most probably from the Lärchberg Carbonate Platform and Dachstein Limestone (D), and diverent not exactly determinable Jurassic deep-water limestone clasts. Sample TB Width: 1.0 cm. H Norian detritusrich Pötschen Limestone from a reef-near facies. The diagenetic overprint of this limestone is low (see also Fig. 19). Sample TB Width: 0.5 cm Dürrnberg in a brooklet and in a meadow during artiwcial excavations (Gawlick et al. 2001b). The metamorphic blocks are contained in a non metamorphic matrix (Missoni and Gawlick 2010) and were overlain by cherty sediments without any thermal overprint. This is evidenced by the good preservation of the radiolarians, which would be otherwise destroyed (Fig. 12). Also all other blocks and slides in the surrounding of this block show no thermal overprint (CAI 1.0). The metamorphic overprint is therefore transported and predates the Late Jurassic emplacement of the slides into the youngest part of the Sandlingalm Basin (compare Fig. 24). Similar metamorphosed slides and blocks appear in the Lammer valley (Gawlick 1997) or in the uppermost Sandlingalm Formation west of Hallstatt (town). However, we were not able to conwrm another slide with strong alteration (CAI 6.0: Braun 1998) near the base of the salt-mine Berchtesgaden. Reinvestigation of the conodonts, partly corroded by evaporitic Xuids, show CAI values of 1.0 (Fig. 19). The veriwcation of metamorphic overprint in Late Triassic rocks before their emplacement in the Late Jurassic radiolaritic basins is of crucial importance for the reconstruction of the Middle to Late Jurassic tectonic history. It conwrms nappe stacking and re-exhumation of buried strata in the area to the south of the currently preserved southern rim of the Northern Calcareous Alps. The same situation was found in the mélange areas of the Western Carpathians (unpublished data) and Albania (Gawlick et al. 2008). Jurassic nappe versus strike-slip concept Alternating coarsening- and Wning-upward trends (easily visible in the Tauglboden Basin) were used as an argument for the manifestation of transpressive strike-slip tectonics (Frank and Schlager 2006). Detailed studies on the stratigraphic record in this basin showed that the Wrst coarsening-upward cycle appeared in Early to Middle Oxfordian time, followed by a relatively long time with condensed sedimentation (latest Oxfordian to Kimmeridgian/Early Tithonian) (Gawlick and Frisch 2003). In the late Early Tithonian resedimentation with slumps, blocks, and slides appeared again (Gawlick et al. 1999b). Reason is the extensional collapse of the Trattberg Rise (Gawlick et al. 2005; Schlagintweit and Gawlick 2007). This marks a new, independent event in the Jurassic geodynamic evolution (Fig. 20). The Jurassic nappe concept is based on: (A) typical coarsening-upward cycles (Fig. 20) in diverent basins with carbonate-clastic, radiolaritic deep-water deposits in the Northern Calcareous Alps and (B) the reconstruction of Triassic-Jurassic facies zones (e.g., Lein 1985; Gawlick et al. 1999a), which follow the general facies arrangements on carbonate shelfs on passive continental margins (e.g., Flügel 2004; Schlager 2005), but with sedimentological and tectonic complications as a widespread feature in the northwestern Tethyan realm in Triassic times (e.g., Schlager and Schöllnberger 1974; Lein 1985, 1987a, b). Important features are detachment horizons in the end- Permian to Early Jurassic passive margin evolution (Fig. 3). Late Anisian normal faults were related to the opening of the Neotethys Ocean. They cut both the Palaeozoic basement and the Late Permian to Pelsonian sedimentary cover including weak sedimentary horizons like evaporites, marls and shales. The Anisian faults were probably reactivated as thrusts during the Jurassic compressional tectonic event (Late Kimmeri(di)c orogeny). During Middle to Late Jurassic shortening the basal detachment climbed up ramps created by the former normal faults (in sense of Nembok et al. 2005). It jumped from the weak Late Permian and Anisian evaporites via Middle Triassic volcano-clastic sediments to Middle to Late Triassic marls and shales and eventually propagated into the weak Early Jurassic sequences (marly limestones). An extensional collapse in the Tithonian suggests that basement uplifts created local orogenic bending, which Wnally led to the formation of extensional high- and

26 162 Facies (2011) 57:

27 Facies (2011) 57: Fig. 17 Carbonate components of the Barremian mass-xow deposits from the type locality of the Rossfeld Formation (Hahnenkamm, Roßfeld). All components derive from a nearby source area and are of Late Jurassic to Early Cretaceous age, similar to the sedimentary succession of Mt. Plassen (Salzkammergut) and the overlying drowning sequence (Gawlick and Schlagintweit 2006). Triassic clasts from the Berchtesgaden nappe resp. the Upper Tirolic nappe or Hallstatt Limestone clasts are completely missing. Matrix mostly consists of carbonate grains of undeterminable origin, and quartz. A Clast of Late Jurassic condensed hemipelagic wackestone with calpionellids, ammonites and aptychi (A), together with a clast of radiolarian packstone of probably Oxfordian age (B). Matrix consists of smaller carbonate clasts. Sample B 162. B Clast of a radiolarian wackestone of Schrambach Formation (A) and of condensed hemipelagic wackestone with calpionellids, ammonites and aptychi (B). Sample B 162. C Lagoonal (A) and forereef (B) component of Plassen Carbonate Platform sensu stricto with chert component (C). Sample B 162. D Spicula-rich Early Kimmeridgian packstone (A) and radiolarian-rich wackestone (Schrambach Formation) (B). Sample B 165. E Reef (A) and lagoonal (B) clast of the Plassen Carbonate Platform together with siliceous radiolarian-rich packstone of the Schrambach Formation (C) in chertywed matrix. Sample B 165. F Saccocoma-Limestone (A), Schrambach Formation (B), and shallow-water Plassen Limestone (C). Matrix contains diverent carbonate and chert clasts beside crinoids. Sample B 165. G Plassen Limestone with Clypeina jurassica Favre and Richards (A) in Wnegrained matrix of diverent carbonate clasts and quartz. Sample B 165. H Shallow-water Plassen Limestone (A), Early Cretaceous condensed hemipelagic wackestone with calpionellids similar to the Late Berriasian drowning sequence of the Plassen Carbonate Platform (B). Sample B 166. Width of all Wgures: 0.67 cm low-angle normal faults, and likely of large-scale strike-slip movements. Upper Tirolic nappe The Eocene Berchtesgaden nappe, as part of the Miocene Berchtesgaden Block (Fig. 2D, compare Figs. 21A, 22), shows a typical sedimentary succession of the inner part of the Triassic to early Middle Jurassic passive continental margin (lagoonal Dachstein Limestone facies Figs. 3, 6). It belongs to the same facies zone as Mt. Watzmann, Mt. Hochkalter, Kehlstein-Göll massif, Steinernes Meer, Hagengebirge, and Tennengebirge massifs (compare Figs. 21, 22). Mt. Untersberg, Kehlstein-Göll massif, and Mt. Trattberg belong to the Jurassic Trattberg Rise, which formed the front of the advancing Upper Tirolic nappe (Figs. 2D, 24A). They all together are part of the Jurassic Upper Tirolic nappe. Therefore, the existence of Triassic isolated carbonate platform patches separated by deepwater channels can not be conwrmed. Hallstatt Mélange The Wrst type of Hallstatt Mélange in the Berchtesgaden Alps, comprising material from the Hallstatt Salzberg facies zone, is dated as Early Callovian to Oxfordian and can be correlated with the Sandlingalm Basin. The Sandlingalm Basin contains a far-travelled radiolaritic basin Wll derived from an area of tectonic shortening further south (southeast in palaeogeographic coordinates). The source area was the eroded Juvavic nappe stack south of the later Sillenkopf Basin. This basin Wll became involved in north (north-west in palaeogeographic coordinates) directed thrusting until the Oxfordian/Kimmeridgian boundary (compare Fig. 24). The Early Kimmeridgian cherty carbonates on top of this mélange belong to the basinal sequence of the Plassen Carbonate Platform sensu lato, representing a period of relative tectonic quiescence (Fig. 20). The second type of Hallstatt Mélange contains material from the Zlambach facies zone. Resedimentation is dated as Late Callovian to Oxfordian. It can be correlated with the Lammer Basin. The western continuation of the Lammer Basin in the Berchtesgaden Alps (Callovian to?middle Oxfordian in age) formed to the north (north-west in palaeogeographic coordinates) of the advancing (Middle Jurassic) Hallstatt nappe front and was situated within the Late Triassic lagoonal Dachstein Limestone facies zone. Further late Late Jurassic tectonic shortening, related to the uplift of the Juvavic nappe pile to the south (south-east in palaeogeographic coordinates) led to gliding along low-angle normal faults of the far-travelled Sandlingalm Hallstatt Mélange onto the Lammer Hallstatt Mélange (Fig. 24B). The Strubberg Formation of the Lammer Basin is preserved in the Gschirrkopf area in the Berchtesgaden Alps, south of the Eocene Berchtesgaden nappe, and in the Watzmann area (Fig. 21A). The Eocene Berchtesgaden nappe and the Watzmann area are today separated by remnants of the overthrusted Sandlingalm Formation (e.g., Wimbachklamm, Antenbichl), squeezed in between these tectonic units by Eocene backthrusting. Remnants of the Sandlingalm Formation are also found further north-east in the Schönau-Berchtesgaden area, as documented by several Hallstatt Limestone blocks. Also the sedimentary succession of the Dürrnberg Block (Figs. 2D, 21A) can be correlated with the mélange of the Sandlingalm Basin. The Hohes Brett Büchsenkopf area and the dismembered blocks and slides of the Torrener-Joch Fault zone belong to the mélange of the Lammer Basin (Fig. 21A). Reinvestigations in the area of the Saalach Fault zone west to south-west of the Berchtesgaden Block revealed Triassic Hallstatt slides of the Sandlingalm and Strubberg formations (Tollmann 1976b). In the central and northern part of the Saalach Fault zone the typical Strubberg Formation and the tectonically overlying Sandlingalm Formation are preserved (Lofer, Unkener Kalvarienberg, Schneizlreuth areas) (Fig. 21A). In contrast, in the southern part of the Saalach fault zone slides of the Zlambach facies zone are missing and the Lärchberg Carbonate Platform as southernmost platform of the Plassen Carbonate Platform sensu lato progrades over Callovian-Oxfordian radiolarites/mélanges

28 164 Facies (2011) 57: Fig. 18 Metamorphosed, recrystallized and slightly deformed Late Triassic conodonts with CAI values of 6.0 from Bad Dürrnberg area. All conodonts show enlarged crystallite sizes, primary conodont morphology is completely destroyed. Conodonts derived from grey reefal meta-limestones. 1 Metamorphosed and recrystallized Epigondolella quadrata Orchard (sample BD 7/99, Early Norian). 2 Detail of surface of metamorphosed Epigondolella quadrata Orchard. 3 Metamorphosed and recrystallized Metapolygnathus communisti Hayashi (sample BD 5/99, latest Carnian to earliest Norian). 4 Detail of surface of 3. 5 Metamorphosed and recrystallized Epigondolella quadrata Orchard (sample BD 7/99, Early Norian). 6 Detail of surface of 5. 7 Metamorphosed and recrystallized Metapolygnathus communisti Hayashi (sample RTW 20, latest Carnian to earliest Norian). 8 9 detail of surface of Metamorphosed and recrystallized Metapolygnathus communisti Hayashi (sample RTW 20, latest Carnian to earliest Norian) detail of surface of 10 forming a post-tectonic cover (e.g., Mt. Gerhardstein, Mt. Dietrichshorn, and Mt. Lärchberghörndl). Lower Tirolic nappe: Tauglboden Mélange In the Berchtesgaden Alps only the southernmost part of the Tauglboden Basin is preserved. The Tauglboden Formation (Dürreckberg area) was overthrusted by the Trattberg Rise (Mt. Kehlstein) immediately after its formation, which demonstrates the northward propagation of the nappe fronts. Contemporaneously the basin axis shifted northward (Figs. 23, 24A). The northern Rossfeld-Göll Block with the western Dürreckberg area is part of the Tauglboden Basin (Gawlick et al. 2002; Fig. 21). The Tauglboden Basin of the Rossfeld area shows a coarsening-upward trend until late Early Cretaceous times (Fig. 4). The sedimentary succession of the Kaltenhausen Block (Missoni 2003) recalls the sedimentary succession of the northern part of the Tauglboden Basin in the Osterhorn Mts. (Fig. 21A). The Sonntagshorn Mts. and

29 Facies (2011) 57: Fig. 19 Non-metamorphosed, recrystallized and slightly broken Late Triassic conodonts with CAI values of 1.0 from the salt-mine Berchtesgaden. Conodonts derived from blocks and components of a polymict mass- Xow deposit (Sandlingalm Formation) of the borehole core TB 152. Greyish limestone (TB 152-3) and red-colored nodular limestone (TB 152-6) are components in this mass-xow deposit. Only in few cases, a corrosion of the surface (by evaporitic Xuids) is visible. 1 Epigondolella quadrata Orchard (sample TB 152-3, Early Norian). Not recrystallized, all details well preserved. 2 Detail of surface of 1. No recrystallization or crystal growth. 3 Metapolygnathus polygnathiformis (Budurov and Stefanov) with well-preserved details (sample TB 152-6, Early Carnian). 4 Detail of surface of 3. Details of conodont surface are relatively well preserved, no recrystallization but partly corrosion. 5 Neogondolella sp. (sample TB 152-6, Early Carnian). 6 Slightly broken Metapolygnathus polygnathiformis (Budurov and Stefanov) (sample TB 152-6, Early Carnian). 7 Gladigondolella sp. (sample TB 152-6, Early Carnian). 8 Detail of surface of 7, with corrosion the Unken syncline (Hahn 1913) also belong to the Tauglboden Basin (Schlager and Schlager 1973; Gawlick et al. 2002). In Late Cretaceous times Gosau(ic) basin(s) were formed in the northern part of the Osterhorn Mts. and further to the west, south-east to south-west of the city Salzburg (from Glasenbach to Bad Reichenhall) (Fig. 21A; Pestal et al. 2009). Post-Gosauic thrusting: formation of the Berchtesgaden nappe From Turonian times on the sedimentary megacycle of the Gosau Group sealed the Jurassic to Early Cretaceous tectonic structures. It started with Xuviatil sediments passing upwards into shallow-marine environment. In the Lattengebirge massif the Gosau sequence (e.g., Herm 1962; Herm et al. 1981) is preserved in N S oriented graben structures (Risch 1993), which were probably related to gosauic strike-slip movements in sense of Decker and Wagreich (2001). Along the northern margin of the Berchtesgaden nappe the Gosau sequence occurs both on top and below the nappe front (e.g., northern slope of Mt. Untersberg; Fugger 1907b; Herm 1962; Herm et al. 1981; Risch 1993) and thus give evidence to post-gosauic (Eocene) out-of-sequence thrusting of the Berchtesgaden nappe. A similar situation is found along the northern margin of the Dachstein nappe in the Salzkammergut region. Contemporaneous south-directed backthrusting of the Berchtesgaden nappe over the Hallstatt Mélange of the Sandlingalm and Strubberg formations

30 166 Facies (2011) 57: Fig. 20 Successions and their correlation of the diverent trench-like basins. The distal Sandlingalm Basin starts to Wll with material from the distal shelf area (Hallstatt Salzberg facies) in the Early Callovian in a coarsening-upward manner until the Oxfordian/Kimmeridgian boundary. The intermediate Lammer Basin starts to Wll with material from the Zlambach facies in the?middle/late Callovian in a coarsening-upward cycle until the Middle/Late Oxfordian. The basis axis migrates during Oxfordian towards the inner part of the Hauptdolomit/ Dachstein Limestone platform and was Wlled in Oxfordian times by material from the Triassic reef rim. The Tauglboden Basin near the central Hauptdolomit/Dachstein Limestone platform starts to Wll in the Early Oxfordian with local material in a coarsening-upward cycle until the Late Oxfordian. Less sediment supply in the starved basins is characteristic for the Late Oxfordian/Kimmeridgian to Early Tithonian time span, whereas the margins of the basins were inxuenced by the prograding Plassen Carbonate Platform in a shallowing-upward cycle. The sediments in the Tauglboden Basin rexect the new tectonic cycle, which started around the Early/Late Tithonian boundary. The Late Tithonian to earliest Cretaceous sedimentary succession in this basin is characterized by a Wning- and deepening-upward cycle. Contemporaneous in the shallow-water succession of the Plassen Carbonate Platform s. str. a deepening cycle started. Colours correspond with Figs. 21, 22, 23, 24, 25. Absolute ages after Gradstein et al. (2004) in the area of Maria Gern and along the Ramsauer Ache (Fig. 21A) can be correlated with according internal structures of the Berchtesgaden nappe (Fig. 22B). These thrusts were formed contemporaneous with other post- Gosauic structures and are part of the same overall kinematic picture. Therefore, the Berchtesgaden nappe was, since the Jurassic orogenic movements, part of the Upper Tirolic nappe close to its front (=Trattberg Rise) (Fig. 22C), but did not form an independent tectonic unit until Eocene times (Fig. 22D). It became a local nappe in a relatively autochthonous position during the post-gosauic orogeny.

31 Facies (2011) 57: Fig. 21 Geologic sketch map based on the Geological Map of Salzburg 1: (Braunstingl 2005) and Pestal et al. (2009). A Preserved parts of Jurassic and Eocene (post-gosauic) nappe fronts Miocene lateral movements: block puzzle The modern block puzzle of the Berchtesgaden Alps evolved during Miocene lateral tectonic extrusion with and Miocene faults and thrusts are shown (based on Frisch and Gawlick 2003; Fig. 2D). Dashed line indicates North South cross section of Fig. 22. B Important CAI-values in the study area E W stretching and N S shortening (Ratschbacher et al. 1991; Frisch et al. 1998). Block segmentation and rearrangement occurred along a conjugate fault system with approximately NNW SSE-trending faults with minor

32 168 Facies (2011) 57: Fig. 22 Generalized geologic cross section through the Berchtesgaden Alps (for location, see Fig. 21). A Cross section after Tollmann (1976b). B Cross section based on the new results. r rotation; d duplex structure. C Tectonic situation of the Berchtesgaden nappe in Eocene time. D DeWnition of the Berchtesgaden unit as part of the Upper Tirolic nappe. Colours correspond with Figs. 20, 21, 23, 24, 25

33 Facies (2011) 57: Fig. 23 Reconstruction of the Toarcian to Callovian geodynamic evolution, basin formation and sedimentary evolution in the Northern Calcareous Alps. Absolute ages after Gradstein et al. (2004). See text for further explanation. NW SE directions refer to Triassic-Jurassic palaeogeographic coordinates (Figs. 2E, 26). Colours correspond with Figs. 20, 21, 22, 24, 25. A Toarcian/Aalenian: Onset of inneroceanic south-eastward subduction in Neotethys Ocean (Gawlick et al. 2008; for discussion see: Nicolas et al. 1999; Shallo and Dilek 2003; Karamata 2006). Late Early to early Late Jurassic inneroceanic subduction is proven by metamorphic soles in the Dinarides ( Ma: Karamata 2006), Albanides ( Ma: Dimo-Lahitte et al. 2001), and Hellenides ( Ma: Roddick et al. 1979; Spray and Roddick 1980). Occurrence of supra-subduction volcanics in ophiolite belt of Albania rexects an inneroceanic subduction stage (Shallo and Dilek 2003; Koller et al. 2006). Contemporaneously, the Wrst ophiolithic mélanges were formed (Babic et al. 2002). Slight south-eastward tilt of distal continental margin, formation of half-grabens in the Hallstatt Zone and horst-and-graben structure in Dachstein Limestone facies zone since the Late Pliensbachian (Adnet Scheck event: Bernoulli and Jenkyns 1974; Böhm et al. 1995) belong to this event. In the Hallstatt Zone the normal faults cut into the Rhaetian Zlambach marls, which probably act as source area for the clay content in the Birkenfeld Formation beside eroded ophiolites. B Early Callovian: Oldest radiolaritic trench-like basin Wll formed in Florianikogel Basin (?Bajocian-Callovian; FB) in the ocean-nearest part. In the Early Callovian continuous continentward propagating thrusting led to the formation of the Sandlingalm Basin (SaB) in the Hallstatt Zone, and to the formation of the Lammer Basin (LB) in the lagoonal Dachstein Limestone facies zone. In this early stage of the Lammer Basin only local material was shed. Continentward a red nodular limestone bulge was formed, which prevailed until the Callovian/Oxfordian boundary (e.g., Huckriede 1971; Mandl 1982) in the area of the later Tauglboden Basin. C Middle to Late Callovian: Further tectonic shortening led to the formation of nappe fronts in the Zlambach facies zone. These nappe fronts shed material from Middle Callovian to Middle Oxfordian time into the Lammer Basin

34 170 Facies (2011) 57: dextral strike-slip movements and approximately WSW ENE-trending faults with larger sinistral strike-slip movements (Frisch and Gawlick 2003). This tectonic event included also block rotations as veriwed by palaeomagnetic results (Pueyo et al. 2007). Below we outline the Torrener-Joch Fault zone, the Königssee Fault system, and the nature of the Berchtesgaden Block (Fig. 2D).

35 Facies (2011) 57: Fig. 24 Reconstruction of the Oxfordian to Tithonian geodynamic evolution, basin formation and sedimentary evolution. Absolute ages after Gradstein et al. (2004). See text for further explanation. NW SE directions refer to Triassic-Jurassic palaeogeographic reconstructions (Figs. 2E, 26). Colours correspond with Figs. 20, 21, 22, 23, 25. A Early to Middle Oxfordian: Due to further tectonic shortening and ongoing obduction of ophiolites (Dinarides: Schmid et al. 2008; Albanides: Gawlick et al. 2008), the southern basin groups were sheared ov and transported to the north west. Contemporaneously, the basin axis in the Lammer Basin propagated to the north west and the newly formed nappe of the Dachstein reef rim shed its material into this basin. In the transitional area of the lagoonal Dachstein Limestone facies to the Hauptdolomit facies, a new nappe front formed (Trattberg Rise), which shed its material into the newly formed Tauglboden Basin. The evaporitic Haselgebirge Mélange (Spötl 1989) contains Late Jurassic authigenic feldspars ( Ma: Spötl et al. 1996, 1998), interpreted as being related to Xuid circulation and mélange formation. The Haselgebirge Mélange carries metamorphosed Hallstatt and Pötschen Limestone blocks as well as volcanic rocks, partly with sodic amphiboles (Kirchner 1980a, b), and oceanic basalts, which were metamorphosed under HP/LT conditions (Vozárová et al. 1999). B Latest Oxfordian: Ongoing obduction of the ophiolites, salt Xow and tectonically uplifted metamorphosed slices of the Hallstatt Zone result in a chaotic mélange. North-westward transport of the Sandlingalm Basin led to overthrusting of the Lammer Basin and north-westward thrusting of the Trattberg Rise (TR) over the south-eastern parts of the Tauglboden Basin. At the north-western edge the Brunnwinkl Rise (BR) as a new nappe front was formed, with the Rofan Basin (RF) as trenchlike basin in front. The evaporitic Alpine Haselgebirge squeezed out in front of the arriving ophiolite nappes and took place on top of the Sandlingalm Formation, until the Early Kimmeridgian. C Early Kimmeridgian: Around the Oxfordian/Kimmeridgian boundary, the formation of shallow-water carbonates on top of the imbricated structures including the obducted ophiolites started. These platforms are summarized as Plassen Carbonate Platform sensu lato with the Wolfgangsee Carbonate Platform (WCP) in the west, the Plassen Carbonate Platform sensu stricto (PCP s. str.), and the Lärchberg Carbonate Platform (LCP) in the east. Radiolaritic basins remain as starved basins in between the individual platforms. Only in the Sillenkopf Basin (SiB) exotic material continued to arrive (compare Fig. 20). D Late Kimmeridgian to Early Tithonian: This time interval was characterized by platform progradation to the adjacent basins. Whereas into the Sillenkopf Basin the platforms on both sides supplied material, the Tauglboden Basin was shielded to the south by the uplifted Trattberg Rise. In the accretionary prism slight uplift started Torrener-Joch Fault zone The geometric conwguration and the palaeogeography around the Torrener-Joch are controversially discussed (e.g., Lebling et al. 1915, 1935; Zankl 1962; Fischer 1965; Tollmann 1985; Plöchinger 1990; Decker et al. 1994; Linzer et al. 1995; Schweigl and Neubauer 1997a; Braun 1998). Since the earliest systematic investigations of the geology of the central Northern Calcareous Alps in the late 1800s, the Torrener-Joch area has been recognized as pervasively broken by innumerable faults (e.g., Gümbel 1861; Böse 1898; Hahn 1913; Lebling et al. 1935). Lebling et al. (1935) observed diverent vertical and horizontal displacements in the basement of the Juvavic Berchtesgadener Schubmasse. Hallstatt Limestone and Lower Triassic sediments were mixed together along high-angle faults in this tectonic zone. Zankl (1962) and Braun (1998) precised the sedimentary record of the Torrener-Joch Fault zone with a discrete Triassic-Jurassic uplift, and connected it with partly subsidence and dismembering of Triassic and Jurassic sediments within the brittle Tirolic units. Zankl (1962) separated the relationships and timing of the diverent stages of deformation in the Berchtesgaden Alps. Decker et al. (1994) pointed out that the Miocene lateral extrusion process resulted in a sinistral transpressional setting along ENE-trending strike-slip faults. Transpression along the Königssee-Lammertal-Traunsee fault is indicated by contractional strike-slip duplexes (referring to the strikeslip duplex model of Woodcock and Fischer 1986) in combination with positive Xower structures (Decker et al. 1994). Examples for the Middle Miocene complex tectonic features were recognized in the Eisgraben valley and the Torrener-Joch area (Decker et al. 1994; Linzer et al. 1995, Schweigl and Neubauer 1997a). Negative Xower structures do also occur, as for instance shown by remnants of the Lammer Basin Wll in the Torrener-Joch area itself. Own Weld surveys after re-evaluation of the geological maps (e.g., Zankl 1962; Pichler 1963; Risch 1993; Decker et al. 1994; Linzer et al. 1995; Schweigl and Neubauer 1997a; Schwerd et al. 1998), the restoration of the block puzzle along the mentioned fault system combined with palaeomagnetic examinations (Pueyo et al. 2007), enabled us to redewne the Torrener-Joch Fault zone. After the palinspastic restoration of the Miocene block movements the Torrener-Joch Fault zone consists of tectonically dismembered blocks and slices originally forming a coherent sedimentary sequence of the Lammer Basin. The arrangement of the individual blocks shows a coherent picture despite the existence of a great variety of structures such as ramps, blind thrusts, and imbrications. Until now exists no agreement about the relative timing and importance of the tectonic processes (Pueyo et al and references therein). The Torrener-Joch Fault zone is redewned on base of the above described results: As part of the Jurassic Hallstatt Mélange this fault zone is bounded to the north by the Trattberg Rise of the Freieck-Göll-Kehlstein Block (Fig. 2D). A possible curvature of the northern bounding fault zone can be documented from Königssee-DörX over the northern Krautkaser brooklet to the area between Mt. Hohes Brett and Mt. Hoher Göll, and further to the Bärenwirt in the eastern Bluntau valley (Figs. 5, 21A). Structural evidence (Schweigl and Neubauer 1997a) indicates the formation of new structures or the reactivation of old ones during subsequent deformation episodes. In sense of Schweigl and Neubauer (1997a) Juvavic thrust slices and nappes (e.g., Mt. Hohes Brett) of the Torrener-Joch Fault

36 172 Facies (2011) 57: zone were thrusted over the Hoher Göll massif in the Neogene, which acquires, according to them, a Tirolic tectonic position. The polyphase movements in the Torrener-Joch Fault zone are also associated with modiwcations of the block arrangement in the Jurassic matrix (e.g., Pueyo et al. 2007). To the south, the Torrener-Joch Fault zone is bounded by a highly fractured zone to the Hagengebirge Block. This can be seen north of the Kesselwand, along the Königsbach brooklet, at the northern slope of Mt. Schneibstein in direction to Torren (Figs. 5, 21A). Königssee Fault system Movements of the Torrener-Joch Fault zone were transferred into the Königssee Fault system in a complex manner. This is evidenced by the disruption of the Sandlingalm, Strubberg, and Tauglboden formations. The amount of displacement along the Königssee Fault system can be quanti- Wed by the marker horizon of the southernmost Hochalm Member of the Kössen Formation (e.g., Golebiowski 1991; Kürschner et al. 2007). The polyphase imbricated fault zone, including the Königssee, Hellbrunn, and Dürrnberg Faults sensu Frisch and Gawlick (2003; Figs. 2D, 5, 21A), which is situated from the Königssee (lake)/königssee Ache (river) up to the Berchtesgaden Ache (river) with an integration of the imbricate-zones of the Faselsberg-, Mitterbach-, Untersalzberg-, Au- and Marktschellenberg-area, dismembered the southern rim of the Kössen Basin. Sinistral lateral movements resulted in a gap in the strike of the Kössen Basin between Mt. Watzmann and the Hagengebirge massif to the east. Further north this fault system separates the Sandlingalm Formation of the Dürrnberg Block from the Kehlstein-Göll Block and the Berchtesgaden Block (Fig. 2D). Berchtesgaden Block The parautochthonous Berchtesgaden Block (including the Eocene Berchtesgaden nappe with the Reiteralpe and Lattengebirge massifs, and Mt. Untersberg as part of the block) belongs to the same facies zone as Mt. Watzmann, Mt. Hoher Göll, and Mt. Kehlstein (Fig. 6). Whereas the Trattberg Rise of Mt. Kehlstein and Mt. Hoher Göll is situated nearly in its relative original palaeogeographic position, the Berchtesgaden Block was repeatedly avected by thrusting and faulting and attained its present position during Miocene and younger strike-slip movements and block rotations. According to Pueyo et al. (2007), the present day block puzzle is the result of both clockwise and counterclockwise rotations after the Eocene thrusting event. Tectonic movements can be determined by the displacement of facies zones and zones of diverent thermal overprint as manifested by the Conodont Colour Alteration Index zones on both sides of the Königssee Fault system as described above (Fig. 21B). Beside the Triassic sedimentary successions, another important argument for a parautochthonous character of the Berchtesgaden Block (and the Eocene Berchtesgaden nappe as part of it) comes from breccia analysis: In the mass-xow deposits or slides of the Lammer Basin, the Sandlingalm Basin, or the Sillenkopf Basin not any Triassic components or detritic materials occur that derived from the Berchtesgaden Block or its associated equivalents. Material from the Berchtesgaden Block is also missing in the mass-xow deposits of the Rossfeld Formation, but occurs in the Tauglboden Basin (compare Fig. 25). In addition, the provenance areas of the components of the Kimmeridgian polymict mass Xows drilled in the salt-mine of Berchtesgaden are clearly diverent to the sedimentary record of the Berchtesgaden Block (Figs. 16, 17). A Cretaceous or older nappe emplacement and an allochthonous origin of the Berchtesgaden nappe can therefore not be conwrmed by these data. Reconstruction of the Mesozoic-Cenozoic tectonic evolution To understand the Jurassic to Cenozoic orogenic evolution of the Austroalpine realm it is essential to interpret the relative roles of tectonic and sedimentary processes of the diverent nappes. The Jurassic mélanges of the Northern Calcareous Alps are composite in origin, and individual examples need to be assigned either to mainly sedimentary or tectonic origins. The Jurassic orogenic evolution is therefore the starting point for geodynamic interpretations of the Northern Calcareous Alps from Cretaceous to recent times. The major steps in their evolution with focus on the Berchtesgaden Alps and including earlier reconstructions are described and presented in schematic sketches in order to visualize the concept (Figs. 23, 24, 25). Jurassic period The Middle to Late Jurassic orogeny in the Northern Calcareous Alps resulted in the destruction of the Neotethysward Middle Triassic to Early Jurassic passive continental margin (the south-eastern margin of Europe; Fig. 2E) which had experienced crustal extension since Late Permian times (Schuster et al. 2001; Schuster and Stüwe 2008). The Triassic to Early Jurassic sedimentary sequences (Figs. 3, 4) of the Northern Calcareous Alps evolved in shore-line parallel facies belts from the inner part of the continental margin (Hauptdolomit facies zone) to the distal shelf area (Hallstatt Zone) (Fig. 2F). In late Early to Middle Jurassic times the geodynamic regime changed to convergent tectonics starting with inneroceanic subduction in the

37 Facies (2011) 57: Fig. 25 Reconstruction of the Tithonian to Aptian geodynamic evolution, basin formation and sedimentary evolution in the Northern Calcareous Alps. Absolute ages after Gradstein et al. (2004). See text for further explanation. NW SE directions refer to Triassic-Jurassic palaeogeographic reconstructions (Figs. 2E, 26). Colors correspond with Figs. 20, 21, 22, 23, 24. A Late Tithonian: Uplift of the metamorphic dome in the eastern part led to the formation of high- and low-angle normal and likely to strike-slip faults. This caused north-westward transport of several mélange slices and uplift and erosion of parts of the Lärchberg Carbonate Platform (LCP). At the north-western edge the Trattberg Rise broke down and the Plassen Carbonate Platform sensu stricto (PCP s. str.) built a new reef rim to the north and shed an enormous amount of carbonate material from there (Oberalm Limestone with intercalated Barmstein Limestone = mass-xows consisting mainly of reefal material). Contemporaneously the Wolfgangsee Carbonate Platform (WCP) drowned (Gawlick and Schlagintweit in press). B Late Berriasian to Early Valanginian: Ongoing uplift in the southeast and increasing sedimentation Wlled the Sillenkopf Basin in Berriasian times. This led to the drowning of the central Plassen Carbonate Platform (PCP s. str.) in the Late Berriasian and to the input of Wrst siliciclastic material in the north-western basin(s) (Schrambach Formation). C Barremian to Aptian: The Valanginian to Barremian time is characterized by a coarsening- and shallowing-upward in the Rossfeld Basin. From Valanginian times onwards mass-xow deposits occur. The Barremian mass-xow deposits in the Rossfeld type area contain material from the Plassen Carbonate Platform sensu stricto and material from the uplifted orogen in the south-east, best explained by a regressive cycle at this time (compare Gradstein et al. 2004) accompanied by intense erosion. The Rossfeld Basin Wll is characterized by a general coarsening- and shallowing-upward cycle until Aptian time

38 174 Facies (2011) 57: Neotethys Ocean. Later, as a consequence the continental margin became obducted by ophiolites and progressively imbricated, starting in the distal shelf area involving the Meliata and Hallstatt facies belts Wrst. Trench-like basins with carbonate-clastic radiolaritic deposits with olistostromes and breccias formed in front of advancing nappes. In the Pliensbachian the sedimentation pattern in the Hallstatt Zone changed to higher sedimentation rates and increasing water depth from condensed cherty limestones to massive and thick dark-grey, clay-rich siliceous marls and cherty limestones. In Toarcian to Aalenian time a thick siliceous marly sedimentary succession (Birkenfeld Formation) was deposited (Figs. 10, 23A). This change is interpreted as an evect of tilting and faulting of the distal passive margin as Wrst impression due to the onset of thrusting in the Neotethys oceanic realm. In the Hallstatt Zone mainly south-eastward dipping normal faults cut into the Zlambach Formation as possible source area for the increased sedimentation of clayey material (Fig. 23A). Another possible source area for the clays can be the accreted Neotethys ophiolites. Contemporaneous a horstand-graben morphology was formed in the lagoonal Dachstein Limestone facies zone, here interpreted as a forebulge. The Wrst stages of thrusting (Fig. 23B) formed the Meliata and distal Hallstatt nappes by imbrication of the outermost part of the former passive continental margin (Fig. 23B). The nappe fronts in the Juvavic domains became completely eroded and can therefore only be reconstructed from the resedimented material in the adjacent trench-like deep-water basins. Matrix dating in several Hallstatt Mélange areas shows that they had formed since Bajocian times. The Florianikogel Formation (Meliata Mélange) in the eastern Northern Calcareous Alps is the Neotethys Ocean nearest preserved relic of a Middle Jurassic radiolarite basin (Fig. 4). This early stage of thrust-related basin formation and sedimentation is not directly observable in the Berchtesgaden Alps, but relics are found to the east in the Lammer Basin type area. Parts of these older basin Wlls occur also as resediments in the younger basins. Further continuous shortening established the proximal Hallstatt nappes (Fig. 23B), also completely eroded today. Trench-like basins in front of these nappes started to form in the Callovian and existed until the Oxfordian. The Wrst clearly reconstructable nappe front is of Early Callovian age. In the Hallstatt realm an accreted nappe stack containing distal Pötschen and Hallstatt Limestone shed its material into the Sandlingalm Basin in Callovian to Oxfordian times. At the same time the Lammer Basin formed further north in the area of the former Dachstein Limestone lagoon (Fig. 23B). In an early stage (Early Callovian) the Lammer Basin received local material from the adjacent nappe front (Klauskogelbach Member). Later, the Zlambach facies zone became imbricated and shed its material into the Lammer Basin (?Middle/Late Callovian to Middle Oxfordian). Around the Callovian/Oxfordian boundary a shift of the basin axis can be correlated with the formation of a new nappe front in the Dachstein Limestone reef zone (Early to Middle Oxfordian) (Figs. 23C, 24A). This shift of the depocenter is well documented: the original depocenter received material from the accreted proximal Zlambach facies zone, whereas the northern depocenter, after the shift of the basin axis, received material from the reefal part of the Late Triassic carbonate platform. The Meliata and Hallstatt nappe stack, though meanwhile completely destructed, served until Late Oxfordian as a source area for the components of the Hallstatt Mélange. This evolution shows a progressive incorporation of continental margin sediments into the thrusting process. In the Early Oxfordian, in the main stage of resedimentation in the Lammer Basin, the Upper Tirolic nappe front (with the Trattberg Rise as its topographic expression) formed to the north-west of this basin by ongoing thrust propagation (Fig. 24A). Contemporaneously, the Tauglboden Basin evolved in front of the Trattberg Rise in the area of the Triassic Hauptdolomit lagoon. The Trattberg Rise was an area of intense erosion and the source area for breccias and mass Xows of the Tauglboden Basin in Early to Middle/Late Oxfordian time. Continued tectonic shortening led to thrusting over the south-eastern margin of the Tauglboden Basin. In?Middle/Late Oxfordian time tectonic shortening again propagated to the north-west, forming the Brunnwinkl Rise (Fig. 24B) as the north-westernmost preserved nappe front (Gawlick et al. 2007b), and the Rofan Basin in front of it (Rofan Breccia, Fig. 4; Gawlick et al. 2009a). In the south-eastern part of the nappe stack a period of relative tectonic quiescence began in latest Oxfordian, in the northern part in Early Kimmeridgian. The Plassen Carbonate Platform sensu lato started its progradation (Fig. 24B, C). From Late Oxfordian or Early Kimmeridgian times onwards ramps and other topographic ridges carrying the Lärchberg Carbonate Platform to the south-east and the Plassen Carbonate Platform sensu stricto to the north-west, Xanked the radiolaritic Sillenkopf Basin (Fig. 24C). This starved basin is interpreted as deep-water remnant basin in between the two prograding carbonate platforms. Late Jurassic shallow-water debris together with exotic clasts was transported through channels coming from the south, mobilized and redeposited since the latest Oxfordian or the Early Kimmeridgian. Due to the spectra of clasts in the Sillenkopf Formation, their provenance areas have been: (A) The accreted Hallstatt units and an overlying shallowwater carbonate platform;

39 Facies (2011) 57: (B) a deeply eroded hinterland further south (probably a part of the crystalline basement of the Northern Calcareous Alps); and (C) an ophiolite nappe pile probably carrying an island arcsimilar to the obducted ophiolites which acted as source for radiolaritic-ophiolitic mélanges in the Dinaridic/Albanide realm (Karamata 2006; Bortolotti et al. 2006). Schuster et al. (2007) and Suzuki et al. (2007) found remnants of Neotethys oceanic crust in the today south-eastern part of the Northern Calcareous Alps, which had been accreted in late Early to Middle Jurassic times together with Triassic radiolarites. This scenario perfectly resembles the situation known from the Mirdita zone in Albania or the Dinaridic Ophiolite Belt (Gawlick et al. 2008, 2009b; Schlagintweit et al. 2008) (compare Fig. 26). Deep-water carbonates in the basinal areas as well as shallow-water carbonates of the Plassen Carbonate Platform sensu stricto (Kimmeridgian to Early Berriasian) formed on top of the Trattberg Rise, i.e., the north-western rim of the Upper Tirolic nappe. This sedimentary cover sealed the Jurassic nappe stack (Figs. 24D, 25) but did not imply farreaching tectonic quiescence. In the late Early Tithonian the Plassen Carbonate Platform sensu stricto on top of the former Trattberg Rise (Figs. 24D, 25A) degraded in an extensional collapse. This event produced high- and lowangle normal faults and probably also large-scale strike-slip movements. The already deeply eroded ramp anticline of the former Trattberg Rise became sealed by the hemipelagic sediments of the Oberalm Formation and the Barmstein Limestone layers at the base and contained therein (Fig. 25B). In contrast, the south-eastern rim of the Tirolic unit with the Kimmeridgian to Tithonian Lärchberg Carbonate Platform became uplifted around the Jurassic/Cretaceous boundary (Figs. 4, 25A). This platform was the provenance area for breccias and slides of the Sillenkopf Basin. Younger sediments in this basin are unexplored and should be the object of further investigation. However, this situation shows that the Tirolic unit remained mobile and displayed considerable diverential vertical and horizontal movements. On the base of this well-restorable Jurassic history we favour a scenario of Middle to early Late Jurassic nappe stacking and latest Jurassic mountain uplift in the so-called but completely destroyed Juvavic nappes. Mountain uplift led to crustal extension with normal faults and probably strike-slip movements in the area further north-west (Fig. 25). Pure strike-slip tectonics as mountain building process in Middle to Late Jurassic time is according to this reconstruction unable to explain all the complex basin formation and sedimentation pattern of the southern Northern Calcareous Alps. Early Cretaceous period Ongoing uplift in the Juvavic nappe stack in the Early Cretaceous was accompanied by continued erosion, which is documented by an increasing supply of ophiolite-bearing clastic material in the former Tauglboden/Oberalm Basin area (Rossfeld Formation; Fig. 25B). The increase of clastic material supply caused drowning of the Plassen Carbonate Platform sensu stricto in Middle to Late Berriasian times and the establishment of a sedimentary succession with increasing siliciclastic input (Schrambach Formation: Middle/Late Berriasian to Valanginian; Rossfeld Formation: Hauterivian to Aptian). This environment is interpreted as underwlled foreland basin with deep-water Xyschoid molasse (Gawlick et al. 2008). The Rossfeld molasse represents the Wnal stage of the Late Kimmeri(di)c mountain building process (Fig. 25C). Around the Barremian/Aptian boundary or in the Early Aptian this basin became Wlled (Fuchs 1968; Plöchinger 1968; Faupl and Tollmann 1979), which is marked by a facies change to fresh-water conditions with local remnants of coal and amber (Grabenwald Formation: Plöchinger 1968). Late Cretaceous to recent period The partly deeply eroded nappe stack of the Northern Calcareous Alps was sealed by the sedimentary sequence of the Gosau Group from Turonian times onwards. The area was avected by further deformation and a sudden subsidence event leading to an abrupt facies change from shallow-marine to deep-water sedimentation (e.g., Faupl and Wagreich 2000). In the today south-eastern Northern Calcareous Alps, the basal Gosau conglomerates contain, among other material, late Early to Middle Jurassic amphibolites (derived from the metamorphic sole of ophiolitic imbricates Schuster et al. 2007) and Anisian to Rhaetian radiolarites (representing the sediment cover of the Neotethys Ocean Xoor Suzuki et al. 2007). This indicates continuous erosion of the accreted Juvavic and ophiolitic nappe complex. Later, in Santonian/Campanian to Maastrichtian times, the mentioned sudden deepening event, which occurred diachronously from west to east (Wagreich 1995), resulted in the deposition of hemipelagic and partly Xysch-like sequences. The facies and the widespread distribution of the deep-water Gosau sediments indicate deposition in a large coherent deep-water basin (Faupl and Wagreich 2000). However, most of this sequence has been eroded in the course of the Eocene orogeny. Eocene out-ofsequence thrusting led to the formation of the Berchtesgaden and Dachstein nappes and other thrust blocks and also avected the Gosau sequence. Palaeogene northward thrusting was accompanied by southward backthrusting (present

40 176 Facies (2011) 57: coordinates) in the entire Northern Calcareous Alps (e.g., Rossner 1972; Plöchinger and Karanitsch 2002). After peneplainization in Late Eocene times, the central and eastern Northern Calcareous Alps were sealed by the Augenstein Formation in Early Oligocene to Early Miocene times (e.g., Lebling et al. 1935; Frisch et al. 2001). In the Miocene they became dissected by the conjugate fault pattern, which formed in the course of lateral tectonic extrusion and caused the elongate shape of the Northern Calcareous Alps and the entire Eastern Alps (Ratschbacher et al. 1991; Linzer et al. 1995; Frisch et al. 1998) and established the modern block puzzle. Discussion Reinvestigation of the Permian to Early Cretaceous sedimentary succession of the Northern Calcareous Alps allows a reconstruction of the sedimentary and tectonic history of the north-western shelf of the Neotethys domain (Figs. 2E, 2F, 26). The Triassic and Early Jurassic sediments were deposited in a rifted, transtensive passive continental margin setting facing the Neotethys Ocean (Figs. 2, 3, 4). Dating of radiolarians (e.g., Halamic and Gorican 1995; Chiari et al. 1996; Gorican et al. 2005; Bortolotti et al. 2006; Gawlick et al. 2008) conwrms a continuous belt of Middle to Late Triassic oceanic lithosphere from Croatia to southern Greece. This implies the existence of a Triassic Ocean (since the Late Anisian: Gawlick et al. 2008) characterized by MORB magmatism and located between Adria-Apulia and Asia (e.g., Bortolotti et al. 2005, 2006; Bortolotti and Principi 2005). Remnants of the Middle to Late Triassic ocean Xoor have also been found in the Western Carpathians (e.g., Dumitrica and Mello 1982; De Wever 1984; Kozur and Reti 1986; Kozur 1991; Kozur and Mock 1997), and in the Northern Calcareous Alps as well (Mandl and Ondrejicková 1991; Kozur and Mostler 1992; Gawlick 1993; Suzuki et al. 2007). Beside reworked material in the Middle Jurassic Florianikogel Basin, Middle to Late Triassic radiolarites and ophiolites occur also as components in Gosauic conglomerates (Suzuki et al. 2007; Schuster et al. 2007). The ocean opened after a Late Permian to Early Triassic stage of crustal extension (Schuster and Stüwe 2008; dated in the Eastern Alps by Schuster et al. 2001). Continental break-up and Wrst formation of oceanic crust in this ocean must be slightly older than the oldest radiolarites deposited on the ocean Xoor (Illyrian Gawlick et al. 2008), and is therefore contemporaneous with the drowning of the Steinalm carbonate ramp in the Late Pelsonian (e.g., Lein 1987b; Gallet et al. 1998). The overall trend in the Triassic evolution was interrupted by characteristic events such as the drowning of the Fig. 26 Palaeogeographic position of the Northern Calcareous Alps in Late Jurassic times (after Frisch 1980; Gawlick et al. 2008). Adria-Apulia platform and equivalents according to Golonka (2002), Vlahovic et al. (2005), and Bernoulli and Jenkyns (2009). In this reconstruction the Northern Calcareous Alps are part of a Jurassic orogen (Neotethyan Belt) striking from the Carpathians to the Hellenides. The Neotethys suture is equivalent to the West-Vardar ophiolite obduction (e.g., Dinaridic Ophiolite Belt) in sense of Schmid et al. (2008); fartravelled ophiolite nappes of the western Neotethys Ocean in sense of Gawlick et al. (2008). The eastern part of the Neotethys Ocean remained open as Vardar Ocean (compare Fig. 23A)