C. Contributed Papers on Northern Studies

Transcription

1 C. Contributed Papers on Northern Studies Saskatchewan Geological Survey 147

2 148 Summary of Investigations 1992

3 Geochemistry of Granitoids in the Western Flin Flon Domain 1 Kevin M. Ansde/1 2 and T. Kurt Kyse? Ansdell, K.M. and Kyser, T.K. (1992): Geochemistry of granitoids in the western Flin Flon Domain; in Summary of Investigations 1992, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep Granitoid rocks, which are an integral part of the evolution of the western Flin Flon Domain, can be classified as syn-volcanic (e.g. Cliff Lake pluton), pre- to syn-tectonic (e.g. Annabel Lake and Reynard Lake plutons), and late-tectonic (e.g. Phantom Lake pluton) (Figure 1) based on cross-cutting relationships and deformation (Byers and Dahlstrom, 1954; Byers et al., 1965; Stauffer, 1984). Recently, accurate U-Pb and Pb-Pb ages have provided absolute age constraints on the timing of these intrusions (Gordon et al., 199; Ansdell and Kyser, 199, 1991); however, the geochronological studies need to be integrated with petrological, and PHANEROZOIC 15:551 Ordovician lc2i:l dolomlth PROTEROZOIC ~ Post-P3 ~ intrusion ~ Pr 1 syn-p3 ~ Intrusions Feldspar porphyry Boundary Intrusions Dior he, gab bro Pre~tectonlc Intrusions Miss I Formation Amlsk Group ""91.,.LH &-.itlil~..,-ro.. -blg,e s... c1ye-,... ~i..y Ri.ilnLalr.. u..mlag1 -- MY1ticl.alw Shear WCF AMISK LAKE km 5 Figure 1 - Geological map of the western Flin Flon Domain (modified after Byers and Dahlstrom, 1954; Byers et al., 1965; Stauffer, 1984; Ashton, 199; Thomas, 199; Reilly, 1991; Slimmon, 1991). The major plutons are identified and the location of the samples in Table 1 are shown. The location of the Phantom Lake granite dyke samples and more detailed sample location maps are in Ansde/1 (1992). Lithostratigraphic blocks: (1) Manistikwan Block, (2) Hook Lake Block, (3) Bear Lake Block (Bailes and Syme, 1989). Abbreviations: SRSZ=Spruce Rapids Shear Zone, WCF=West Channel Fault, MCSZ=Macdonald Creek Shear Zone, RCSZ = Robinson Creek Shear Zone, WLF = Wilson Lake Fault, ALSZ =Annabel Lake Shear Zone, WASZ = West Arm Shear Zone, and RLF = Ross Lake Fault. (1) Func:lec:I t>y University (NSERC)-lnc:lustry (Cameco) Research Grant (2) Conlinenlal Geoscience Division. Geo191ca1 Survey of Canada, 61 Booth Street. Ottawa. Ontario, K1A OE8. (3) Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan, S7N OWO. Saskatchewan Geological Survey 149

4 major, trace and isotopic geochemical studies to fully define the evolution of these igneous rocks. This report summarizes major and trace element, and isotopic data obtained from the Boot Lake-Phantom Lake intrusive complex, and the Reynard Lake and Annabel Lake plutons in the western Flin Flan Domain, Saskatchewan. These data provide constraints on the petrogenesis of these plutons. Field and petrological observations are outlined by Ansdell (1992), and descriptions of these plutons are also provided by Byers and Dahlstrom (1954), Byers et al. (1965), Galley and Franklin (1987) and Thomas (1989, 1991). A preliminary discussion on the geochemistry of the Boot Lake-Phantom Lake intrusions is provided by Watters (1991). The petrology and geochemistry of the syn-volcanic Cliff Lake pluton are described by Bailes and Syme (1989). 1. Geological Setting The Flin Flan Domain is one of the lithotectonic elements of the Trans-Hudson Orogen, which is considered to be the collision zone between the Archean Superior and Hearne Provinces. The oldest rocks in the western Flin Flon Domain, the Amisk Group (Figure 1). are a sequence of tholeiitic to calc-alkaline volcanic and volcaniclastic rocks, varying in composition from basaltic to rhyolitic. They represent a complex mixture of intraoceanic island arc, back arc, and possibly mid-ocean ridge extrusive rocks (Stauffer et al., 1975; Gaskarth and Parslow, 1987; Bailes and Syme, 1989; Thom et al., 199). In the Flin Flan area, the magmas were derived by partial melting of a mantle source relatively depleted in Nd (Chauvel et al., 1987). Two felsic volcanic rocks have been dated using U-Pb in zircons and yield ages of 1886 ±2 Ma (Gordon et al., 199) and / -3 Ma (Syme et al., 1991). Unconformably overlying the Amisk Group are fluvial molasse-type conglomerates and sandstones of the Missi Formation (Stauffer, 199). Missi metasedimentary rocks in the Flin Flan area were deposited between 1854 and 184 Ma (Ansdell et al., 1991). These supracrustal rocks have been variably deformed by up to five deformational events (Stauffer and Mukherjee, 1971; Bailes and Syme, 1989; Fedorowich eta/., 1991). The major shear zones (Figure 1) developed under ductile conditions during the third phase of deformation, and were then reactivated under brittle-ductile conditions during the development of the Embury Lake fold (P4; Fedorowich et al., 1991). The Ross Lake fault system (P5) crosscuts the Embury Lake fold and has a dominantly brittle character. Peak regional metamorphism, varying in grade from prehnite-pumpellyite to amphibolite facies, is broadly synchronous with P3 and P4, and post-dates intrusion of the granitoids (Digel and Gordon, 1991 ). However, in the lower grade metamorphic regions, peak thermal conditions were attained during intrusion of the granitoids as suggested by the presence of amphibolite grade contact aureoles. 2. Major and Trace Element Geochemistry Major and trace element compositions of representative samples are given in Table 1; all samples analyzed are tabulated by Ansdell (1992). The granitoids define a calcalkaline trend on an AFM plot, and all plutons are metaluminous except for the more felsic phases of the Reynard Lake and Annabel Lake plutons which are peraluminous. Overall, the major element compositions of the granitoids are typical of intra-oceanic island arc systems (Brown, 1982). In general, Al23, CaO, MgO, Fe23, Ti2, and P2s decrease as Si2 content increases, whereas 1<2 and Na2 increase with Si2 content (Figure 2). These trends would be expected as a result of crystal-liquid fractionation processes during the evolution of a parental mafic magma, and are related to the decrease in modal proportions of ferromagnesian minerals and the increase in K-feldspar and the albite component in plagioclase with increasing Si2. The range in Si2 content and the variation of the major element oxides with Si2 are similar for the Boot Lake, Reynard Lake, and Annabel Lake plutons, implying that they likely developed from magmas of similar composition and by similar processes. Boot Lake and Phantom Lake plutons were considered to represent part of the same intrusive complex (Galley and Franklin, 1987), although Watters (1991) and this study provide geochemical data which indicate that the Phantom Lake pluton is not simply the result of continuing crystal-liquid fractionation of the same magma from which the Boot Lake pluton crystallized. The range in Si2 exhibited by the Phantom Lake pluton (6.7 to 67.9 wt.%) overlaps the range exhibited by the Boot Lake pluton (53.2 to 69.5 wt.%), and for a given Si2 content, the Phantom lake pluton has higher K2, Al23 and Nc12 and lower MgO, CaO and Fe23 contents. The Phantom Lake pluton thus exhibits its own correlated trends among major elements, which parallel the trends exhibited by the Boot Lake pluton. The distinction between the Boot Lake and Phantom Lake plutons is emphasized in Harker diagrams plotting Si2 against Ba and Sr (Figure 3). Ba and Sr are highly enriched in the Phantom Lake pluton and tend to decrease with increasing Si2 content. The other plutons, including the Boot Lake pluton, also exhibit a negative correlation between Si2 and Sr, but a positive correlation between Si2 and Ba. Rb generally increases with Si2 in all plutons (Ansdell, 1992), and the mutual inter-relationships between Si2, K2, Na2, Rb, Ba, and Sr are probably a function of plagioclase fractionation and concentration of K-feldspar in the more Si2 rich phases. All plutons exhibit slightly LREE enriched patterns, although samples from the Phantom Lake pluton are more fractionated (LaN/YbN = 2.4 to 34.4) than samples from the Boot Lake (5.2 to 5.4), Annabel Lake (2.9 to 14.7), or Reynard Lake (13.7 to 19.4) plutons (Figure 4). Eu anomalies are absent or slightly negative, although the magnitude of the anomaly increases with increasing HREE. In general, the plutons are LREE enriched, and have flat HREE patterns. 15 Summary of Investigations 1992

5 Table 1 - Representative major and trace element data from granitoids in the W&stam Flin Flon Domain. Reynard Lake Annabel Lake Boot Lake Phantom Lake Phantom Lake dyke Si Ti Al Fe MnO MgO CaO K Na P2~ L Total Be Rb Sr Ba Cs Ta Th u Zr Hf Nb y Sc v Cr <1 27 La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Note: Major element oxides (wt.%) and Rb, Ba, Sr, Zr, and Cr concentrations (ppm) by XRF; REE (ppm) by ICP-MS after sodium peroxide fusion procedure; all other trace element concentrations (ppm) by ICP-MS after dissolution in HF-HNQ3. Detailed analytical procedure described in Ansdell (1992). Trace element abundance diagrams (Thompson et al., 1984; Pearce et al., 1984), are useful when comparing variations in element concentrations between suites of rocks. The Flin Flon plutons are enriched in the more incompatible elements (Sr, K, Rb, Ba, Th, and locally Ce), but depleted in Ta, Nb, Hf, Zr, Sm, Y, and Yb relative to ocean-ridge granite (Figure 5). The patterns are similar to those exhibited by granites that formed in oceanic is- land arc environments related to subduction (Pearce et al., 1984). Small Ta-Nb relative depletions and extreme depletions of Y and Yb, that are characteristic of such an environment, are evident in plutons of the western Flin Flan Domain. 3. Oxygen and Neodymium Isotope Geochemistry The granitoid rocks in the western Flin Flan Domain yield whole rock 18 values that range between 7.5 / oo (Boot Lake diorite) and 11.3 / oo (Reynard Lake granite) (Table 2), and exhibit increasing 18 values with increasing Si2 contents. These values overlap with primary o 18 values exhibited by granitoids worldwide (Taylor and Sheppard, 1987). However, petrographic evidence indicates that many of the granitoids in the western Flin Flon Domain have undergone subsolidus recrystallization during which primary minerals were altered (e.g., saussuritized feldspars; replacement of biotite by chlorite) or deformed (e.g. undulose extinction in quartz). The affect of such alteration on the oxygen Saskatchewan Geological Survey 151

6 ~ 16.. i ~ i Al23 Boot Lake.. b Phaneom Lake 6 ~ O Annabel Lake 8.. eao.. Reynmn! lake ls... i 4...,~ allf.,....'bo so 7 8 so Fe i ~ "a) ;~ 2 -..,. MgO... 4.o : o.,... ~~ so <2 Na , o I..,... t.... o i a so ,.... i ,,. TI P ,. ::,t!.6 i.6 ~.4...JJ.o.4 * o... \.2... ~.:\<>.. w.2. so Si2 (wt. %) Si2 (wt. o/o) Figure 2 Harker variation diagrams for major elements from the Annabel Lake, Reynard Lake, Boot Lake, and Phantom Lake plutons. Data from Table 1 and Ansde/1 (1992). 152 Summary of Investigations 1992

7 Figure 3 - Harker variation diagrams for Ba and Sr. Symbols as in Figure 2. quartz-mineral pairs from the Annabel Lake pluton yield tempera Boot lake tures ranging from 485 to 35 C, whereas from the Phantom lake pluton a quartz-hornblende pair Phantom Lake yields a temperature of 65 C and a quartz-magnetite pair a temperature of 575 C Phantom Lake 119 dyke The higher temperatures obtained from the Phantom Lake pluton indicate that quartz, hornblende, and magnetite did not undergo postcrystallization, open system oxygen isotope exchange with an external fluid. This is consistent with the relatively young age of the pluton, and its lack of petrographic alteration. Annabel Lake The Annabel Lake quartz diorite yields lower oxygen isotope equilibration temperatures, exhibits.._ more visible alteration, and represents an early phase of one of the 16 Reynard Lake older, syn-tectonic plutons in the area. Thus, after initial crystallization and cooling, it is likely that fluid circulation, driven by other younger plutons in the region, may have interacted with and altered the primary minerals and allowed continued oxygen isotope exchange to relatively low temperatures. La Ce Pr Nd Sm F.u Gd Th Dy Ho F.r Tm Yb i.aj La Ce Pr Nd Sm Eu Gd Th Dy Ho Er Tm Yb Lu Figure 4 - Chondrite-normafized rare earth element diagrams for representative granitoid samples from the western Flin Flon Domain. Data from Table 1. isotopic composition of minerals was tested by analyzing mineral separates from the Phantom Lake granite (sample 89-25), the youngest and petrographically least altered pluton, and an Annabel Lake quartz diorite (sample 89-8), which is one of the older syn-tectonic plutons in the region (Table 2). Normal igneous quartzfeldspar fractionation should be between about 1.2 and 2. /oo (Taylor and Sheppard, 1987), whereas quartzfeldspar fractionations in the western Flin Flon Domain ranged from -.6 to 2.5 / oo. This indicates oxygen isotope disequilibrium between these minerals, likely related to saussuritization of feldspars. Oxygen isotope Nd isotope systematics are commonly used as tracers of the evolution of the mantle and continental crust because significant changes in Sm/Nd ratios typically require a partial melting event or mixing of Sm and Nd from different rock units (Faure, 1986; Collerson et at., 1988). The Sm/Nd ratio of igneous rocks tends to remain constant after crystallization and thus the 143 Nd/ 144 Nd ratio of these rocks evolve along linear trends. The possible source of a magma can be determined by calculating the 143 Nd/1 44 Nd ratio at the time Saskatchewan Geological Survey 153

8 .. ~ c I'll...,, CII CD Cl.:::: c I'll CD u ~ u a: K Rb Th Ba Ta Rb Th K Ba Ta Nb Hf Sm Ce Zr V Vb Nb Hf Sm Yb Ce Zr V Annabel Lake Reynard Lake 8 Ph an tom 119 Lake dyke Phantom Lake Boot Lake Fig1.1re 5 - Element variation diagrams normalized to ocean-ridge granite (Pearce et al., 1984) for granitoids in the western Flin Flon Domain. Data from Table 1. of formation and comparing it with 143 Nd;1 44 Nd ratios exhibited by possible sources at that time, such as depleted mantle, undepleted mantle, and previously formed crustal rocks. end values, which are the 143 Ndj1 44 Nd ratios of the rocks at the time of crystallization relative to chondrite uniform reservoir (CHUR) or bulk earth, for granitoids from the western Flin Flan Domain, are calculated using the Pb-Pb zircon ages given in Table 2, and range from -1. to +4.5 (Table 2). These end values are compared to the Nd isotopic composition of possible magma sources in Figure 6. The Amisk Group Nd-evolution line has been constructed using the Sm and Nd data of Chauvel et al. (1987), the U-Pb ages obtained by Gordon et al. (199) and Syme et al. (1991), and the range of end values for Amisk Group volcanic rocks obtained by Stern and Syme (1992). The end(t) values for the Annabel Lake, Reynard Lake and Boot Lake plutons fall on or close to the Amis k Group evolution line suggesting that the felsic magmas could have been derived by partial melting of rocks similar to Amisk Group rocks or, more likely, from the same source as the volcanic rocks. Stern and Syme ( 1992) obtained similar end values for the Cliff Lake (+4.2), Neso Lake (+4.), and Lynx Lake (+3.8) plutons in Manitoba, and also postulated derivation of these magmas by partial melting of the lower portions of the arc crust. The Phantom Lake pluton and associated dykes have distinctly lower end values (-1. to +1.4), and cannot have been derived by partial melting of a depleted mantle source, or typical Amisk Group volcanic rocks. Direct partial melting of an Archean source is also impossible, although the lower end values indicate that the magma source for the Phantom Lake pluton most likely included a component from an older source. The Phantom Lake pluton postdates Missi Formation molasse sedimentary rocks, which contain Archean/Early Proterozoic detrital zircons (Ansdell et al., 1991). Thus, Nd that had been resident in the crust for a period of time prior to the intrusion of the Phantom Lake pluton may have been included in the Phantom Lake magma by direct partial melting of Missi-type sedimentary rocks, or by subduction of similar sediments to a zone of partial melting in the upper mantle. The whole rock end values are only indicative of a possible magma source if the whole rock samples have remained closed to Sm and Nd during subsolidus recrystallization and alteration. Recently, Barovich and Patchett (1992) showed that whole rock Sm-Nd isotope systematics are generally unaffected by deformation and low-grade metamorphism. However, Sm-Nd mineral isochrons, derived by analyzing mineral separates already analyzed for their oxygen isotopic composition, from the Annabel Lake and Phantom Lake plutons, do not yield reasonable ages (Ansdell, 1992). Thus, it appears that on the mineral scale the samples have remained open with respect to Sm and Nd during subsolidus recrystallization and alteration, similar to both the O and Rb-Sr systems (see Ansdell (1992) for discussion on Rb-Sr isotope systematics of these whole-rock samples and mineral separates), perhaps providing empirical evidence that closure temperatures for Sm-Nd exchange in minerals in granitic rocks may be lower than generally believed. However, it may be that the Sm-Nd systematics of whole rock samples were not significantly affected during inter-mineral exchange. 4. Petrogenesis and Summary The Annabel Lake, Reynard Lake, Boot Lake, and Phantom Lake plutons are generally metaluminous, define a calc-alkaline trend on an AFM diagram, are enriched with respect to ocean-ridge granites in large-ion lithophile elements (LILE) and depleted in high field strength elements (HFSE), and have Rb, Y and Nb concentrations and whole rock o 16 values that are indica- 154 S1.1mmary of Investigations 1992

9 Tabla 2 - Selected isotopic data obtained from granitoids in the westem Flin Flon Domain. Sample number and description arno (perm ii) Annabel Lake quartz diorite 84 WR WR 9.2 hbl 5.4 bt 3. plag 8.1 qz 1.6 Reynard Lake pluton 89 diorite WR 16 granite WR 89-4 granite WR qz Boot Lake quartz diorite 93 WR Phantom Lake granite and dykes 119 WR WR WR 9.4 qz 1.1 hbl 6.3 mt 1.6 fsp 9.5 mic pc 1.7 Note: Equilibration temperatures( C) qz-hbl qz-bt qz-plag qz-hbl qz-mt qz.fsp Age Epsilon Nd (Ma ±2 sigma) 186 ±6 186 ± ± ± ± ± Sample locations in Figure 1 and Ansdell (1992); equilibration temperatures calculated using the fractionation factors of Bottinga and Javoy (1975); ages from Ansdell and Kyser (199, 1991). Abbreviations: WR c whole rock, hbl = hornblende, qz c quartz, bt = biotite, plag = plagioclase, fsp = feldspars, mt"' magnetite, mic pc= microcline phenocryst. Analytical procedures in Ansdell (1992). e~~~~~~~~~~~~~~~~~~ De lered manue ~; e Amlsk A,nisk. Group :"k. - Group O y fh;;,tom Lk Annabtl Llik CHUR Phntom Lakt 16-+-~~~~~~~~~~~~~~~~ Time (Ma) Figure 6 - cnd values of granitoids in the western Flin Flon Domain in relation to possible sources for magmas. Data from Table 2. tive of volcanic arc granites. All of these general characteristics are typical of granitoids that were derived by subduction-related processes at convergent plate margins. The Phantom Lake pluton has high K 2 and Na 2, extremely enriched Ba and Sr contents, more LREE enriched patterns, and lower cnd(t) values than the other plutons. It also exhibits its own correlated major element trends, which parallel the trends exhibited by the Boot Lake pluton. These differences suggest that the Phan- -1. tom Lake magma was derived from a geochemically distinct source region relative to the earlier plutons and has no simple petrogenetic relationship with the Boot Lake pluton. However, the overall pattern exhibited by normalized trace element abundance diagrams is similar to those exhibited by granitoids in oceanic island arcs, emphasizing that subduction-related processes were still important in the production of the Phantom lake magma. Possible sources for the magmas that eventually crystallized as granitoids in the Flin Flon area are the subducted slab, the overlying asthenospheric mantle wedge, the lower portions of the developing island arc crust, or older continental crust. Thom et al. (199) indicate that the most likely source of the island arc magmas was the mantle wedge, which could have been enriched in the LILE by introduction of aqueous fluids from the subducted slab. The decoupling of HFSE and LILE in the granitoids suggests that the involvement of direct partial melts from the slab is unlikely. High E:Nd values for the Annabel lake, Reynard Lake, and Boot lake plutons do not support melting of older continental crust, but can be explained by partial melting of recently formed Amisk Group-type rocks in the roots of the growing island arc system, or by partial melting of an underlying enriched mantle wedge. The high Ba and Sr and lower cnd values exhibited by the Phantom Lake pluton cannot be attributed to differentiation from the Boot Lake magma, but are probably related to a distinct source region. The Phantom Lake pluton postdates molasse sediments, which contain earlier Proterozoic and Archean detrital zircons indicating that older crust was being eroded (Ansdell et al., 1991). Similar crust may have shed detritus, which was then subducted, and this sedimentary signature was ultimately incorporated into the Phantom Lake magma. Direct partial melting of earlier Proterozoic crust is a possibility, but there is no evidence, as yet, for the existence of such crust, and thus a model involving contamination of the source region as a result of subduction processes is preferred. Harker diagrams showing the variation of major and trace elements with Si2. and REE patterns, provide constraints on the minerals involved in the development of the plutons. The rocks are dominated by feldspars, hornblende and quartz, with variable amounts of biotite and accessory apatite, zircon, sphene, and Fe-oxides; the more mafic phases also contain rare relict pyroxenes. Crystallization and removal of these phases in various proportions should explain the observed Saskatchewan Geological Survey 155

10 geochemical patterns. Distinct trends showing decrease in Fe23, MgO, Cao, Al23, Ti2, P2s. and Sr with increasing Si2 suggest that continuous removal of hornblende, plagioclase, Fe-Ti oxides or sphene, and apatite likely occurred. REE patterns are generally consistent for each pluton, although they cover a limited range of Si2 content. The REE patterns exhibiting insignificant Eu anomalies are similar to those that would develop as a result of combined hornblende and plagioclase fractionation from an initial quartz gabbro magma (Gromet and Silver, 1987). The sub-solidus isotopic evolution of the Annabel Lake and Phantom Lake plutons is complicated by alteration, and recrystallization during deformation and metamorphism. The oxygen isotopic composition of quartz, hornblende and magnetite in the Phantom Lake pluton preserve reasonable crystallization temperatures, whereas minerals in the Annabel Lake pluton record substantially lower oxygen isotope equilibration temperatures (Table 2). Sr and Nd isotope systematics of these minerals do not yield reasonable mineral isochrons, which is indicative of open system exchange, and is likely related to the presence of a fluid phase. The timing of fluid interaction cannot be constrained using these data, but is probably complex and multi-stage. However, evidence is lacking for high-temperature fluid movements in the western Flin Flan Domain after those associated with mesothermal gold deposition at about 176 Ma (Ansdell and Kyser, in press). 5. References Ansdell, K.M. (1992): Evolution of the western Flin Flon Domain with special reference to epigenetic gold mineralization; Unpubl. Ph.D. thesis, Univ. of Saskatchewan, 36p. Ansdell, K.M. and Kyser, T.K. (199): Age of granitoids from the western Flin Aon Domain: An application of the singlezircon Pb-evaporation technique; in Summary of Investigations 199, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 9-4, p ~ (1991): Plutonism, deformation and metamorphism in the Proterozoic Flin Flon greenstone belt, Canada: Limits on timing provided by the single-zircon Pb-evaporation technique: Geol., v19, p ~-- (in press): Mesothermal gold mineralization in a Proterozoic greenstone belt: western Flin Flon Domain, Saskatchewan; Econ. Geo!. Ansdell, K.M., Stauffer, M.A., Kyser, T.K., and Edwards, G. (1991): Detrital zircons from Missi metasedimentary rocks, Flin Flon Basin: Constraints on age and provenance; in Summary of Investigations 1991, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 91 4, p Ashton, K.E. {199): Geology of the Snake Rapids area, Flin Flon Domain {Parts of NTS 63L-9 and -1); in Summary of Investigations 199, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 9-4, p4-12. Bailes, A.H. and Syme, E.C. (1989): Geology of the Flin Flon - White Lake area; Manit. Energy Mines. Geol. Rep. GR 87-1, 313p. Barovich, K.M. and Patchett, P.J. (1992): Behavior of isotopic systematics during deformation and metamorphism: A Hf. Nd and Sr isotopic study of mylonitlzed granite; Contrib. Mineral. Petrol., v19, p Bottlnga, Y. and Javoy, M. (1975): Oxygen isotope partitioning among the minerals in igneous and metamorphic rocks; Reviews in Geophysics and Space Physics, v13, p Brown, G.C. (1982): Cale-alkaline intrusive rocks: Their diversity, evolution, and relation to volcanic arcs; in Thorpe, R.S. (ed.), Andesites: Orogenic Andesites and Related Rocks, Wiley, p Byers, A.A. and Dahlstrom, C.D.A. (1954): Geology and mineral deposits of the Amlsk-Wildnest lakes area, Saskatchewan; Sask. Dept. Miner. Resour., Rep. 14, 177p. Byers, A.A., Kirkland, S.J.T., and Pearson, W.J. (1965): Geology and mineral deposits of the Flin Aon area, Saskatchewan; Sask. Dept. Miner. Resour., Rep. 62, 95p. Chauvel, C., Arndt, N.T., Kielinzcuk, S., and Thom, A. (1987): Formation of Canadian 1.9 Ga old continental crust. 1: Nd isotopic data; Can. J. Earth Sci., v24, p Collerson, K.O., Van Schmus, R.W., Lewry, J.F., and Bickford, M.E. (1988): Buried Precambrian basement in southcentral Saskatchewan: Provisional results from Sm-Nd model ages and U-Pb zircon geochronology; in Summary of Investigations 1988, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 88-4, p Digel, S. and Gordon, T.M. (1991): Prehnite-pumpellyite to amphibolite facies metamorphism near Flin Aon, Manitoba; Current Research, Pt. C, Geo!. Surv. Can., Paper 91-1C, p Faure, G. (1986): Principles of Isotope Geology (2nd edition); John Wiley and Sons, 589p. Fedorowich, J., Stauffer, M., and Kerrich, R. (1991): Structural setting and fluid characteristics of the Proterozoic Tartan Lake gold deposit, Trans-Hudson Orogen, northern Manitoba; Econ. Geo!., v86, p Galley, A.G. and Franklin, J.M. (1987): Geological setting of gold, copper, tungsten and molybdenum occurrences in the Phantom Lake region; in Summary of Investigations 1987, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 87-4, p Gaskarth, J.W. and Parslow, G.R. (1987): Proterozoic volcanism in the Flin Flon greenstone belt, east-central Saskatchewan, Canada; in Pharoah, T.C., Beckinsale, A.O., and Rickard, D. (eds.). Geochemistry and Mineralization of Proterozoic Volcanic Suites; Geol. Soc. Lon., Spec. Publ. 33, p Gordon, T.M., Hunt, PA, Bailes, A.H., and Syme, E.C. (199): U-Pb ages from the Flin Flon and Kisseynew belts, Manitoba: Chronology of crust formation at an Early Proterozoic accretionary margin; in Lewry, J.F. and Stauffer, M.A. (eds.), The Early Proterozoic Trans-Hudson Orogen of North America, Geol. Assoc. Can., Spec. Pap. 37, p Gromet, LP. and Silver, L.T. (1987): REE variations across the Peninsular Ranges batholith: Implications for batholithic petrogenesis and crustal growth in magmatic arcs; J. Petrol., v28, p Summary of Investigations 1992

11 Pearce, J.A., Harris, N.B.W., and Tindle, A.G. (1984): Trace element discrimination diagrams for the tectonic interpreta tion of granitic rocks; J. Petrol., v25, p Reilly, B.A. (1991): Revision bedrock geological mapping, Mystic Lake-Kaminis Lake area (Parts of NTS 63K 12 and 63L 9); in Summary of Investigations 1991, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 91 4, p9-15. Slimmon, W.L. (1991): Revision bedrock geological mapping, Table Lake area (Part of NTS 63L-9); in Summary of In vestigations 1991, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 91-4, p16-2. Stauffer, M.A. (1984): Manikewan: AA early Proterozoic ocean in central Canada, its igneous history and orogenic closure; Precam. Res., v25, p (199): The Missi Formation: AA Aphebian m_o_,l,...as_se_ deposit in the Reindeer Lake Zone of the Trans- Hudson Orogen, Canada; In Lewry, J.F. and Stauffer, M.A. (eds.), The Early Proterozoic Trans-Hudson Orogen of North America, Geel. Assoc. Can., Spec. Pap. 37, p Stauffer, M.A. and Mukherjee, A.C. (1971): Superimposed deformations in the Missi metasedimentary rocks near Flin Flon, Manitoba; Can. J. Earth Sci., v8, p Stauffer, M.A., Mukherjee, A.C., and Koo, J. (1975): The Amisk Group: All Aphebian(?) island arc deposit; Can. J. Earth Sci., v12, p Stern, A.A. and Syme, E.C. (1992): Nd-isotopic evolution of the Flin Aon Belt, Trans-Hudson Orogen Transect; Lithoprobe Workshop 1992 Report, p Syme, E.C., Hunt, P.A., and Gordon, T.M. {1991): Two U-Pb zircon ages from the western Flin Flon belt, Trans-Hudson orogen, Manitoba; In Radiogenic Age and Isotopic Studies, Rep. 4, Geol. Surv. Can., Pap. ~2. p Thom, A., Arndt, N.T., Chauvel, C., and Stauffer, M. (199): Flin Aon and western La Ronge belt, Saskatchewan: Products of Proterozoic subduction-related volcanism; in Lewry, J.F. and Stauffer, M.A. (eds.), The Early Proterozoic Trans-Hudson Orogen of North America, Geol. Assoc. Can., Spec. Pap. 37, p Thomas, D.J. (1989): The geology of the Douglas Lake-Phantom Lake area (part of NTS 63K 12 and -13); in Summary of Investigations 1989, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 89-4, p ,---. (199): New perspectives on the Amisk Group and regional metallogeny, Douglas Lake-Phantom Lake area, northern Saskatchewan; in Summary of Investigations 199, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 9-4, p13-2. (1991): Revision bedrock geological mapping, --.B~o-o~t,~e-g Lake-Birch Lake area (Parts of NTS 63K-12 and 63L 9); in Summary of Investigations 1991, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 91-4, p2 8. Thompson, R.N., Morrison, M.A., Hendry, G.L., and Parry, S.J. (1984): AA assessment of the relative roles of crust and mantle in magma genesis: AA elemental approach; Phil. Trans. Roy. Soc. Lon., va31, p Watters, B.R. (1991): Uthogeochemical studies in the East Amisk Lake area; in Summary of Investigations 1991, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 91-4, p Saskatchewan Geological Survey 157

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