Depositional Environments and Hydrocarbon Potential of Northern Ionian Sea

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1 Depositional Environments and Hydrocarbon Potential of Northern Ionian Sea Vasiliki Kosmidou George Makrodimitras Nick Papatheodorou

2 Contents Area of Interest Studied Dataset Workflow SWIT and Paleolatitude Heat flow BHT and Vitrinite Reflectance Data Geochemical Data Erosion, Uplift and Flexural Rigidity 3D model Paleoenvironments Conclusions

Area of Interest Northern Ionian sea is the greater area of western

Geologically, the area is bounded to the north by the Otranto Basin and

On the west there is the Apulian escarpment and from there westwards

On the east, there is the deep basinal area, the South Adriatic Basin,

3 Area of Interest Northern Ionian sea is the greater area of western Corfu and Paxos islands in Offshore Western Greece. Geologically, the area is bounded to the north by the Otranto Basin and to the south by the Kefalonia strike-slip fault. On the west there is the Apulian escarpment and from there westwards starts the Calabrian Ridge. On the east, there is the deep basinal area, the South Adriatic Basin, that is bounded on its eastern margin by the front of the Hellenides thrust-and-fold belt. The central part of the basin is the Apulian platform. Apulian Platform

4 Studied Dataset 6000km 2D seismic data (approx.) 2D multiclient seismic survey (2012, PGS) Legacy seismic surveys Yannadhes Paxi Gaios 1X Paxi 1 4 wells Paxi-Gaios 1X Paxi 1 East Erikousa 1 Yannadhes 1

Workflow SURFACE GRIDS Interpret key horizons in TWT. Depth conversion using sonic data. MODEL Depth converted horizon grids used in a 3D model with Haq's (1987) * sea level curves.

5 Workflow SURFACE GRIDS Interpret key horizons in TWT. Depth conversion using sonic data. MODEL Depth converted horizon grids used in a 3D model with Haq's (1987) * sea level curves. Tectonic uplift, subsidence and sediment compaction were not modelled. * Modified by Miller, 2005 THERMAL PARAMETERS Sediment water interface temperature diagram from Wygrala (1989). Paleolatitude for Ionian Sea based on Torsvik et al. (2012). Heat flow scenario based on analogue cases and reference studies. Calibration data available from the AOI. EROSION, UPLIFT AND FLEXURAL RIGIDITY Erosion identification in seismic. Uplift scenario from literature. Flexural rigidity of Nm (Allen & Allen, 2013) ORGANIC GEOCHEMISTRY Rock eval data from AGIP Rock - Eval Report for Paxi-Gaios 1X samples for Kerogen Type categorisation and source rock quality estimation

o C 20-25 o C 25-30 o C 25-30 o C >30 o C

6 Latitude( o ) SWIT and latitude changes Time(Ma) 5-10 o C <5 o C o C o C o C o C o C >30 o C North Ionian Sea Modified from Wygrala (1989)

7 Heat flow scenario

8 BHT and Vitrinite Reflectance Data

9 Very Little SR or no SR Gas SR Gas SR?

Erosion 500 m Seismic data suggest important erosional unconformities in the AOI.

In the basinal areas unconformities are observed due to the introduction of calciturbidites in

: Three main erosional unconformities in the Miocene sequence with the later and more important

10 Erosion 500 m Seismic data suggest important erosional unconformities in the AOI. : Three intra-carbonate erosional unconformities (also observed in Italian outcrops). In the basinal areas unconformities are observed due to the introduction of calciturbidites in the basin. : Three main erosional unconformities in the Miocene sequence with the later and more important one the messinian unconformity. : Three Mass Transport Complexes associated with earthquake and thrust activity. Pliocene-Pleistocene MTC Miocene unconformities Cretaceous intra-carbonate unconformities

Uplift and Flexural Rigidity Uplift Flexural Rigidity o Uplift started in middle Pleistocene (Doglioni et al., 1994) associated with the deposition of two loads on the margins of Apulia.

11 Uplift and Flexural Rigidity Uplift Flexural Rigidity o Uplift started in middle Pleistocene (Doglioni et al., 1994) associated with the deposition of two loads on the margins of Apulia. This, together with the KTF and isostasy, affected the geometry, tension and pressure profile of the AOI. o o o Allen & Allen (2013) suggest a displacement of the fore bulge towards Apennines by asymmetry of flexural rigidity of Adriatic. Hellenides D= Nm Apennines D= 6 * Nm o In the Middle Pleistocene, the platform was uplifted while the adjacent basinal areas were affected by subsidence (Mastronuzzi et al. 2011). o The maximum deflection is assumed w 0 =10km o Uplift rates from 0.4 to 0.2 ( ) mm/yr (Cianrafi et al. 1988; Doglioni et al., 1994). (From Allen & Allen, 3 rd, 2013)

12 Triassic Terrestrial to shallow marine environment? Neotethys A-B

platforms where we expect the deposition of formations

13 Triassic High Slopes indicative of Rifting Restricted basinal, marine environment adjacent to the carbonate platforms where we expect the deposition of formations equivalent to Burano Fm. C-D

14 Jurassic

15 Jurassic

16 Jurassic

17 Jurassic

18 Jurassic Extensive platform A-B Topographic highs that favour the development of Build Ups

19 Jurassic Rimmed Platform C-D

20 Early Cretaceous

21 Early Cretaceous

22 Early Cretaceous

23 Early Cretaceous Isolated build-ups A-B

24 Early Cretaceous Extensive platform Isolated build-ups C-D

25 Late Cretaceous

26 Late Cretaceous

27 Late Cretaceous Carbonate Build-Ups covered by pelagic sediments

28 Late Cretaceous Subaerial erosion of the carbonate platform led to the development of calciturbidites transferred into the basin impeding the carbonate build up development A-B

29 Late Cretaceous Steep platform slope and intense erosion leads to redeposited carbonate sediments in the slope and proximal basin C-D

30 Paleogene Prograding sediment infill from the east/ thrust propagading

31 Paleogene Prograding sediment infill from the east/ thrust propagading

32 Paleogene Prograding sediment infill from the east/ thrust propagading

33 Paleogene Prograding sediment infill from the east/ thrust propagading

34 Paleogene Prograding sediment infill from the east/ thrust propagading

35 Miocene Prograding sediment infill from the east/ thrust propagading

36 Messinian Highest slopes at the eastern margin match the seismic interpretation suggesting higher sediment infill from the east

37 Messinian Messinian Salinity Crisis Sea Level Drop

38 Messinian Messinian Salinity Crisis Sea Level Drop

39 Messinian Messinian Salinity Crisis Sea Level Drop

40 Messinian Messinian Salinity Crisis Sea Level Drop

41 Messinian Messinian Salinity Crisis Sea Level Drop

42 Messinian Messinian Salinity Crisis Sea Level Drop

43 Messinian Zanclean Flooding

44 Messinian Zanclean Flooding

45 Messinian Zanclean Flooding

46 Messinian Zanclean Flooding

47 Messinian Zanclean Flooding

48 Messinian Zanclean Flooding

49 Messinian Highest slopes at the eastern margin match the seismic interpretation suggesting higher sediment infill from the east A-B

50 Messinian Highest slopes at the eastern margin match the seismic interpretation suggesting higher sediment infill from the east C-D

51 Plio - Pleistocene Excessive deepening due to the KTF and the Uplift

52 Plio - Pleistocene Excessive deepening due to the KTF and the Uplift

53 Plio - Pleistocene Excessive deepening due to the KTF and the Uplift

54 Plio - Pleistocene Excessive deepening due to the KTF and the Uplift

55 Plio - Pleistocene Excessive deepening due to the KTF and the Uplift

56 Plio - Pleistocene Excessive deepening due to the KTF and the Uplift A-B

57 Plio - Pleistocene C-D

58 Lateral Migration of the basin depocenter from Jurassic to Present (C-D)

59 Paleoenvironments

60 Conclusions North Ionian Sea is characterized by a wide shallow water platform with occasionally steep slopes to the west and a deep basin to the east In the basinal part, three isolated carbonate build ups can be identified in the 2D seismic Rock-Eval data suggest good to excellent source rocks Paleothermal data suggest necessary conditions for the maturation of hydrocarbons in the past 3D model allowed the identification of high slope areas indicating the best locations for the development of bioclastic slope aprons and the location of carbonate build-ups 3D model helped the understanding of the lateral change of the basin depocenter due to the thrust activity

61 Questions?

Greece offers new offshore exploration opportunities

Greece offers new offshore exploration opportunities Kostis Oikonomopoulos George Makrodimitras Yannis Bassias Hellenic Hydrocarbon Resources Management SA Athens, Greece GREECE S OFFSHORE TENDER FIG.