New U-Pb SHRIMP and Sm-Nd Isotopic Results for the Bassett Lake Leucogabbro, La Ronge Domain, Reindeer Zone

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1 New U-Pb SHRIMP and Sm-Nd Isotopic Results for the Bassett Lake Leucogabbro, La Ronge Domain, Reindeer Zone Ralf O. Maxeiner 1, Nicole Rayner 2 and Robert A. Creaser 3 Information from this publication may be used if credit is given. It is recommended that reference to this publication be made in the following form: Maxeiner, R.O., Rayner, N. and Creaser, R.A. (2017): New U-Pb SHRIMP and Sm-Nd isotopic results for the Bassett Lake leucogabbro, La Ronge Domain, Reindeer Zone; in Summary of Investigations 2017, Volume 2, Saskatchewan Geological Survey, Saskatchewan Ministry of the Economy, Miscellaneous Report , Paper A-3, 9p. Abstract As part of the Saskatchewan government s La Ronge Horseshoe project, a new U-Pb SHRIMP zircon result has been obtained for the Bassett Lake leucogabbro, located at the southern end of the La Ronge Domain in the southwestern Reindeer Zone of the Trans-Hudson Orogen. The Bassett Lake intrusion has the appearance of a lopolith, turned on its side and younging to the east, and consists of a number of texturally variable units of leucogabbro and gabbro, with minor components of anorthosite, gabbronorite, melagabbro and pyroxenite. The intrusion hosts the Triangle Lake Cu-Ni occurrence, which is in the central part of the pluton and consists of titaniferous magnetite, pyrrhotite and chalcopyrite. The Vidgy Lake gold occurrence is along the northern margin of a dioritic intrusion, where it cuts the Bassett Lake intrusion and felsic to intermediate volcanic rocks. A marginal zone of the Bassett Lake intrusion consists of taxitic leucogabbro and gabbro that is locally characterized by primary magmatic textures including cross-bedded rhythmic layering and irregular pegmatitic zones. The sample collected for geochronology is a very coarse-grained to pegmatitic leucogabbro to gabbro, containing between 25 and 35% clinopyroxene, 2% magnetite, with a balance of plagioclase. Abundant, concentrically zoned zircons were recovered from the leucogabbro and yielded a single population with a weighted mean 207 Pb/ 206 Pb age of 1846 ±4 Ma, which is interpreted as the crystallization age of the leucogabbro. This new U-Pb zircon result indicates that the Bassett Lake intrusion is coeval with a diverse suite of gabbro, monzodiorite, monzonite and granite dated between 1848 Ma and 1838 Ma. However, whereas other members of this suite have variably evolved ɛnd values ranging from -3.5 to +2.6, the Bassett Lake leucogabbro has a juvenile ɛnd value of +4.2 (t = 1900 Ma). These plutonic rocks are time equivalents of the Mullock Lake assemblage, which has been interpreted as a nonmarine supracrustal succession that has a considerable volcanic-subvolcanic component of calc-alkaline arc derivation and a possible forearc affinity. The Bassett Lake intrusion cuts surrounding volcano-plutonic rocks, suggesting that these surrounding rocks are older than the Mullock Lake assemblage, and are likely related to circa 1879 Ma volcanism documented in the La Ronge Domain. The Bartlett Lake dyke suite, consisting of a texturally and compositionally varied set of fine-grained, porphyritic felsic to mafic rocks, is widespread throughout the Bassett and Bartlett lakes area. This dyke suite is interpreted to be related to volcanic rocks interlayered with the Mullock Lake assemblage and is thought of as being genetically associated with the 1846 Ma Mullock Lake volcanic rocks. Plutons such as the 1846 Ma Bassett Lake intrusion and the 1844 to 1838 Ma Rachkewich Lake pluton could represent the source magmas for these feeder dykes. Keywords: Paleoproterozoic, Reindeer Zone, Trans-Hudson Orogen, La Ronge Domain, Bassett Lake, Bartlett Lake, U-Pb geochronology, zircon 1. Introduction This paper summarizes a U-Pb sensitive high-resolution ion microprobe (SHRIMP) result of a sample collected at Bassett Lake (Figure 1) during the 2014 field season as part of the La Ronge Horseshoe project (Maxeiner and MacLachlan, 2010; Maxeiner, 2014). Previous U-Pb and Sm-Nd isotopic results related to the same project have been published in Maxeiner and Kamber (2011), Maxeiner et al. (2012, 2013, 2014, 2015), and Maxeiner and Rayner (2016). Including this sample, a total of 12 new U-Pb zircon results have now been published as part of the Horseshoe project and are summarized in Table 1. 1 Saskatchewan Ministry of the Economy, Saskatchewan Geological Survey, th Avenue, Regina, SK S4P 3Z8 2 Natural Resources Canada, Geological Survey of Canada, 601 Booth Street, Ottawa, ON K1A 0E8 3 University of Alberta, Department of Earth and Atmospheric Sciences, 1-26 Earth Sciences Building, Edmonton, AB T6G 2E3 Although the Saskatchewan Ministry of the Economy has exercised all reasonable care in the compilation, interpretation and production of this product, it is not possible to ensure total accuracy, and all persons who rely on the information contained herein do so at their own risk. The Saskatchewan Ministry of the Economy and the Government of Saskatchewan do not accept liability for any errors, omissions or inaccuracies that may be included in, or derived from, this product. Saskatchewan Geological Survey 1 Summary of Investigations 2017, Volume 2

2 Figure 1 Geological map of the Bassett Lake area (main part of figure) and domains of the Reindeer Zone (inset: SC = Sask Craton); location for the Bassett Lake sample, discussed in this report, is indicated (RM ). Yellow box on inset map outlines area of detailed map. Saskatchewan Geological Survey 2 Summary of Investigations 2017, Volume 2

3 Table 1 Summary of U-Pb zircon results obtained between 2010 and 2017 as part of the La Ronge Horseshoe project. Sample Number Rock Name Domain Technique UTM-E UTM-N Reference Age, Error, Interpretation in Ma 2 sigma Igneous Rocks RM Rachkewich Lake Glennie SHRIMP Maxeiner et al., Igneous crystallization monzodiorite RM Rachkewich Lake Glennie SHRIMP Maxeiner et al., Igneous crystallization monzonite RM Hebden Lake rhyolite Kisseynew SHRIMP Maxeiner et al., Igneous crystallization RM RM RM RM Sedimentary Rocks RM Bassett Lake leucogabbro Little Crooked Lake granodiorite Birch Rapids granitic gneiss Black Bear Island Lake syenogranite Mullock Lake conglomerate La Ronge SHRIMP this report Igneous crystallization Glennie SHRIMP Maxeiner et al., Igneous crystallization Rottenstone SHRIMP Maxeiner et al., Igneous crystallization Rottenstone SHRIMP Maxeiner et al., Igneous crystallization Kisseynew QUADROPOLE Maxeiner and Kamber, RM Nemeiben Lake psammite Glennie SHRIMP Maxeiner et al., RM RM RM Nistowiak Lake gneisses Little Deer Lake psammite Sturdy Island feldspathic quartzite Glennie SHRIMP Maxeiner et al., Rottenstone SHRIMP Maxeiner et al., Rottenstone SHRIMP Maxeiner et al., Metamorphism Footnote: Ages are weighted means of Pb 207/ Pb 206 ages; a Quadrupole is a mass spectrometer consisting of four cylindrical rods set parallel to each other. UTM coordinates are given in NAD83, Zone 13. The only historical age determination in the Bassett Lake area is from an island at the north end of Bartlett Lake, where a sample collected by Heaman et al. (1991) yielded a preliminary U-Pb zircon age of 1885 ±3 Ma. This sample, based on the coordinates provided and the mapping by Thomas (1993), came from a diabase dyke, which was interpreted in the present study to cut granodioritic to tonalitic rocks. There is, however, no detailed discussion of the sample or its analytical result contained in Heaman et al. s paper, nor are the data or concordia plot provided. Therefore, the reliability of the age cannot be verified and the interpretation of the age is up for discussion. The aim of dating the Bassett Lake leucogabbro was to test if this pluton is an older (i.e., circa 1870 to 1880 Ma), broadly synvolcanic intrusion, as suggested by the historical circa 1885 Ma age date (Heaman et al., 1991) from the Bartlett Lake area (Figure 1), or if it is part of the younger suite of circa 1848 to 1837 Ma plutonic rocks identified throughout the La Ronge Horseshoe project area (Maxeiner et al., 2014). Circa 1870 Ma (Turek et al., 2000) gabbroic intrusions in the Lynn Lake area in Manitoba, which lies on strike with the La Ronge Domain roughly 240 km to the northeast, host a number of nickel-copper-cobalt deposits, including a depleted mine, therefore the gabbroic rocks in Saskatchewan may have potential for similar mineralization. In addition, the age of the Bassett Lake pluton will provide a minimum age for the intermediate to mafic volcanic rocks that it intrudes, and it will give a maximum age for the tonalitic and dioritic rocks that intrude it. U-Pb geochronology was carried out using the SHRIMP at the J.C. Roddick Ion Microprobe Laboratory at the Geological Survey of Canada in Ottawa. SHRIMP analytical procedures followed those described by Stern (1997), and Stern and Amelin (2003). U-Pb results are presented in Table 2, with analytical details given in the footnotes. Saskatchewan Geological Survey 3 Summary of Investigations 2017, Volume 2

4 2. Local Geology of the Bassett Lake Area The Bassett Lake intrusion is a zoned, gabbroic pluton at the southern end of the La Ronge Domain in the western part of the Reindeer Zone (Figure 1). The pluton has the appearance of a lopolith, turned on its side and, based on cross-bedded igneous layering, is younging toward the east. It is dominated by a number of texturally variable units of leucogabbro and gabbro, and minor components of anorthosite, gabbronorite, melagabbro and pyroxenite. The Bassett Lake pluton has intruded a succession of felsic to mafic volcanic rocks, which represent the main volcanic sequence of the La Ronge Domain (Thomas, 1993). It is itself cut by younger dioritic and tonalitic rocks (Thomas, 1987; Maxeiner, 2014; Maxeiner and Rayner, 2016). The intrusion hosts the Triangle Lake Cu-Ni occurrence (Saskatchewan Mineral Deposit Inventory number (SMDI #) 0819), which is in the central part of the pluton (Figure 1) and consists of titaniferous magnetite, pyrrhotite and chalcopyrite. The Vidgy Lake gold occurrence (SMDI #2294) is along the northern margin of a dioritic intrusion, where it cuts the Bassett Lake intrusion and felsic to intermediate volcanic rocks. 3. Geochronology Results A unit of taxitic (a term coined by Russian geologists for variably textured gabbros with grain size varying from medium to pegmatitic) leucogabbro and gabbro (unit RLt) forms the marginal zone of the Bassett Lake intrusion on its western margin (Figure 1). Taxitic texture is characterized by strongly varying grain size from medium grained to locally pegmatitic on a decimetre scale, which results in a seriate-textured rock (Figures 2A, 2B). The mafic mineral content varies from 15% to 40%, with leucocratic compositions dominating. Primary magmatic textures have locally been preserved in the gabbro, including examples of crossbedded rhythmic layering (Figure 2C) and irregular pegmatitic zones. It is one of these more coarse-grained sections contained within a unit of leucograbbro that was targeted as a U-Pb geochronology sample. The sample is a very coarse-grained to pegmatitic leucogabbro to gabbro (Figures 2A, 2B), containing between 25 and 35% clinopyroxene, 2% magnetite, with a balance of plagioclase. Figure 2 Outcrop photographs of leucogabbro: A) Strongly varying grain size, from medium to very coarse, in leucogabbro causes taxitic textures; sample location for RM (station RM ; UTM m E, m N 4 ). B) Close-up view of leucogabbro at the sample site; mafic minerals are dominated by amphibolitized pyroxene; same location as A. C) Well-developed cross-bedded cumulate layering (station RM ; UTM m E, m N). Abundant clear, colourless stubby prisms of zircon with well-preserved facets and terminations were recovered from the leucogabbro (Figure 3A). In back-scattered electron (BSE) images (Figure 3B), concentric zoning is faint but easily seen and consistently observed. Twenty-five analyses (Table 2) were carried out on 23 individual zircon grains, yielding a simple population with a weighted mean 207 Pb/ 206 Pb age of 1846 ±4 Ma (n = 25, MSWD = 0.52), 4 Datum for UTM coordinates is NAD 83, Zone 13. Saskatchewan Geological Survey 4 Summary of Investigations 2017, Volume 2

5 which is interpreted as the crystallization age of the leucogabbro. No information on the age of metamorphism is apparent from the data. The dated leucogabbro sample was also processed to obtain Sm-Nd isotopic results and generated an ɛnd value of +4.2 (t = 1900 Ma) (Table 3). Previous analytical results for the time-equivalent Rachkewich Lake intrusions, between 15 and 35 km to the west and southwest, gave ɛnd values for three samples of diorites and monzodiorites between +0.1 and +2.6 (t = 1900 Ma) (Maxeiner et al., 2015). A monzonite and quartz monzonite yielded ɛnd values of -1.6 and -3.5 (ibid), respectively. If all of these samples are indeed part of the same plutonic suite, it would suggest various levels of crustal contamination involving older crust during emplacement of the intrusions. Figure 3 U-Pb results for the Bassett Lake Intrusion (RM ): A) Microprobe image of clear, colourless stubby zircon grains used for analysis. B) Back-scattered electron (BSE) image of representative zircon grains (black circles show analyzed spots; numbers refer to individual zircon grains). C) Concordia plot of U-Pb results showing a weighted mean age of 1846 ±4 Ma. MSWD = mean square of weighted deviates. Saskatchewan Geological Survey 5 Summary of Investigations 2017, Volume 2

6 Table 2 Results of SHRIMP U-Pb analyses carried out on a leucogabbro sample (RM ) from the Bassett Lake intrusion in the southern La Ronge Domain; station RM (UTM m E, m N). RM Pegmatitic leucogabbro, Bassett Lake Ages (Ma) Spot name U Th Th Yb Hf Hf 204 Pb f(206) Pb* 208* Pb 207* Pb 206* Pb Corr 207* Pb 206 Pb ± 206 Pb 207 Pb ± 207 Pb Disc. (ppm) (ppm) U (ppm) (ppm) Yb 206 Pb % ± % (ppm) 206* Pb % ± 235 U % ± 238 U % ± Coeff 206* Pb % ± 238 U 238 U 206 Pb 206 Pb (%) E E E E E E E E E E E E E E E E E E E E E E E E E Notes (see Stern, 1997): Spot name follows the convention x-y.z; where x = sample number, y = grain number and z = spot number. Multiple analyses in an individual spot are labelled as x-y.z.z. Uncertainties are reported at 1s and are calculated by using SQUID , rev. 15 Oct f(206) 204 refers to mole percent of total 206 Pb that is due to common Pb, calculated using the 204 Pb method; common Pb composition used is the surface blank ( 204 Pb/ 206 Pb: ; 207 Pb/ 206 Pb: ; 208 Pb/ 206 Pb: ). * refers to radiogenic Pb (corrected for common Pb). Disc.: Discordance given as difference between measured 206 Pb*/ 238 U ratio and the expected 206 Pb*/ 238 U ratio at t = 207 Pb*/ 206 Pb* age, in percent. Calibration standard 6266; U = 910 ppm; age = 559 Ma; 206 Pb/ 238 U = Analytical details for SHRIMP mount IP831 (sample RM ): 16 µm spot, 6- na intensity, 6 scans. Error in 206 Pb/ 238 U calibration 0.8% (included). Standard error in standard calibration was 0.17% (not included in above errors but required when comparing data from different mounts). No mass fractionation correction was required (measured 207 Pb/ 206 Pb age of secondary standard z1242 = 2680 ±3 Ma, n=24, 1 reject). Saskatchewan Geological Survey 6 Summary of Investigations 2017, Volume 2

7 Table 3 Sm-Nd isotopic data for sample RM (S.E. = standard error.) Sample RM Rock Type Sm (ppm) Nd (ppm) 147 Sm/ 144 Nd 143 Nd/ 144 Nd 2 S.E. end0 143 Nd/ 144 NdT TDM Ga ~TMa TMa endt leucogabbro N/A Footnotes: For analytical and laboratory details please see Maxeiner et al., TDM not calculated for samples with 147 Sm/ 144 Nd > All samples relative to La Jolla 143 Nd/ 144 Nd = Uncertainty is 2 standard errors on 143 Nd/ 144 Nd. TDM uses the linear Model of Goldstein et al., Discussion The U-Pb zircon result presented here provides a useful time marker for mafic plutonism in the southern La Ronge Domain. It was anticipated that the gabbro would be of similar age to the 1871 Ma gabbros of the Lynn Lake belt in Manitoba (Turek et al., 2000). Instead, the age of the Bassett Lake leucogabbro (1846 Ma ±4 Ma) is similar to that of the Hanson Lake gabbro (1847 ±4 Ma; Heaman et al., 1994) and the Reynard Lake gabbro (1849 ±2 Ma; Stern et al., 1993), both in the western Flin Flon Domain. Closer to the present study area, the Bassett Lake leucogabbro falls in the same age range as a diverse suite of 1848 to 1838 Ma monzonite, monzodiorite and granite (Maxeiner and Kamber, 2011; Maxeiner et al., 2012, 2014) found throughout the La Ronge Horseshoe project area. These plutonic rocks have been interpreted as being part of a forearc that developed along the western edge (present day) of the Flin Flon Glennie complex as a result of easterly-directed subduction (Maxeiner and Morelli, 2014). The plutonic rocks are time equivalents of the Mullock Lake assemblage, components of which have been interpreted as a nonmarine supracrustal succession (Stauffer, 1990; Maxeiner and Morelli, 2014) that has a considerable volcanicsubvolcanic component of calc-alkaline arc derivation. A felsic volcanic rock interbedded with sedimentary rocks of the Mullock Lake assemblage was emplaced at 1846 ±4 Ma (Maxeiner et al., 2013) several kilometres to the east of the Bassett Lake area. This assemblage unconformably overlies psammopelitic to pelitic sedimentary rocks and volcanoplutonic rocks of the La Ronge and Glennie domains, which, based on previous work in the Waddy and McLennan lakes area 90 km to the northeast, were emplaced between 1879 and 1880 Ma (Van Schmus et al., 1987). Based on these relative timing relationships, the felsic to mafic volcanic rocks that are cut by the Bassett Lake intrusion on its northern and southern margins (Figure 1) are most likely related to the older volcano-plutonic successions rather than the Mullock Lake assemblage. The Bartlett Lake dyke suite (Thomas, 1987; Maxeiner and Rayner, 2016), which is found intruding the volcanic rocks surrounding the Bassett Lake intrusion, consists of a texturally and compositionally varied suite of fine-grained, porphyritic felsic to mafic rocks that have been interpreted as being genetically related to volcanic rocks interlayered with the Mullock Lake assemblage (Maxeiner and Rayner, 2016). They are thought of as potentially representing a feeder area for the proposed Mullock Lake forearc assemblage (Maxeiner and Morelli, 2014). Plutons such as the Bassett Lake intrusion and the Rachkewich Lake pluton (Maxeiner and Fischbuch, 2012) could represent the source magmas for such feeder dykes. The 1885 ±3 Ma Bartlett Lake diabase dyke mentioned in a paper by Heaman et al. (1991) is likely part of these feeder dykes, its age possibly being a result of zircon inheritance from the older volcanic successions that the dykes would have passed through. Finally, the new age for the leucogabbro indicates that the dioritic and tonalitic intrusions cutting the Bassett Lake pluton are younger than 1846 Ma. 5. Economic Significance As outlined in the introduction, 1870 Ma mafic to ultramafic plutons in the Lynn Lake area carry significant potential in regards to magmatic copper-nickel sulfide mineralization (Pinsent, 1980; Turek et al., 2000). The established age for the copper-nickel bearing Bassett Lake intrusion broadens the range of metalliferous mafic intrusions considerably, and allows exploration to target a much wider range of plutons. The proposed geotectonic model for the 1848 to 1837 Saskatchewan Geological Survey 7 Summary of Investigations 2017, Volume 2

8 Ma Mullock Lake assemblage and its subvolcanic to plutonic roots, involves emplacement in an entirely intraoceanic, forearc setting along the western edge of the growing Flin Flon Glennie complex (Maxeiner and Morelli, 2014). Although arcs and forearcs are not traditionally considered fertile ground for the formation of magmatic-hosted copper-nickel mineralization (e.g., Eckstrand and Hulbert, 2007), there are instances of such deposits in both Precambrian and Phanerozoic time (e.g., Sappin et al., 2008; Wei et al., 2013). 6. Acknowledgments Samantha Van De Kerckhove and Ken Ashton of the Saskatchewan Geological Survey are thanked for their constructive reviews of an earlier version of the typescript. 7. References Eckstrand, O.R. and Hulbert, L.J. (2007): Magmatic nickel-copper-platinum group element deposits; in Mineral Deposits of Canada: A Synthesis of Major Deposit-Types, District Metallogeny, the Evolution of Geological Provinces, and Exploration Methods, Goodfellow, W.D. (ed.), Geological Association of Canada, Mineral Deposits Division, Special Publication 5, p Goldstein, S.L., O Nions, R.K. and Hamilton, P.J. (1984): A Sm-Nd isotopic study of atmospheric dusts and particulates from major river systems; Earth and Planetary Science Letters, v.70, p Heaman, L.M., Kamo, S.L., Delaney, G.D., Harper, C.T., Reilly, B.A., Slimmon, W.L. and Thomas, D.J. (1991): U-Pb geochronological investigations in the Trans-Hudson Orogen, Saskatchewan: preliminary results by the ROM Laboratory in ; in Summary of Investigations 1991, Saskatchewan Geological Survey, Saskatchewan Energy and Mines, Miscellaneous Report 91-4, p Heaman, L.M., Maxeiner, R.O. and Slimmon, W.L. (1994): U-Pb geochronological investigations in the Trans-Hudson Orogen, Saskatchewan; in Summary of Investigations 1994, Saskatchewan Geological Survey, Saskatchewan Energy and Mines, Miscellaneous Report 94-4, p Maxeiner, R.O. (2014): La Ronge 'Horseshoe' project: geological context of the Bassett Lake mafic intrusion and the surrounding volcanoplutonic complex (parts of NTS 73P/10 and /11), La Ronge Domain; in Summary of Investigations 2014, Volume 2, Saskatchewan Geological Survey, Saskatchewan Ministry of the Economy, Miscellaneous Report , Paper A-11, 12p. Maxeiner, R.O. and Fischbuch, R.W. (2012): La Ronge Horseshoe project: bedrock geology of the Little Crooked Black Bear Island lakes area, Glennie and Rottenstone domains (parts of NTS 73P/06, /11, /12); in Summary of Investigations 2012, Volume 2, Saskatchewan Geological Survey, Saskatchewan Ministry of the Economy, Miscellaneous Report , Paper A-9, 21p. Maxeiner, R.O. and Kamber, B.S. (2011): La Ronge Horseshoe project: bedrock geology of the Hebden Lake area at the transition between the western Glennie Domain and southern Kisseynew and La Ronge domains (parts of 73P/07); in Summary of Investigations 2011, Volume 2, Saskatchewan Geological Survey, Saskatchewan Ministry of Energy and Resources, Miscellaneous Report , Paper A-7, 20p. Maxeiner, R.O. and MacLachlan, K. (2010): Preliminary bedrock geology of the eastern Nemeiben Lake area in the vicinity of the Elizabeth Lake Cu deposit and the Dunlop Cu-Ni deposit, western Glennie Domain (parts of NTS 73P-03, -06, and -07); in Summary of Investigations 2010, Volume 2, Saskatchewan Geological Survey, Saskatchewan Ministry of Energy and Resources, Miscellaneous Report , Paper A-7, 17p. Maxeiner, R.O. and Morelli, R. (2014): The Mullock Lake Assemblage: remnants of an Ma forearc basin?; in Summary of Investigations 2014, Volume 2, Saskatchewan Geological Survey, Saskatchewan Ministry of the Economy, Miscellaneous Report , Paper A-7, 14p. Maxeiner, R.O. and Rayner, N.M. (2016): La Ronge Horseshoe project: summary of recent field investigations at Bartlett, Sulphide and Nemeiben lakes, and analytical details of a 2045 Ma gneissic syenogranite in the southern Rottenstone Domain; in Summary of Investigations 2016, Volume 2, Saskatchewan Geological Survey, Saskatchewan Ministry of the Economy, Miscellaneous Report , Paper A-3, 25p. Saskatchewan Geological Survey 8 Summary of Investigations 2017, Volume 2

9 Maxeiner, R.O., Matthews, M. and Morelli, R. (2013): La Ronge Horseshoe project: bedrock geology of the Nistowiak-Mountain- Otter lakes area, Glennie and Kisseynew domains (parts of NTS 73P/07, /08, /09, and /10); in Summary of Investigations 2013, Volume 2, Saskatchewan Geological Survey, Saskatchewan Ministry of the Economy, Miscellaneous Report , Paper A-7, 22p. Maxeiner, R.O., Rayner, N.M. and Creaser, R.A. (2014): U-Pb SHRIMP and Sm-Nd isotopic results from the La Ronge Horseshoe project: evidence for a new Archean inlier and a 1.84 Ga arc complex related to subduction under the Flin Flon Glennie complex; in Summary of Investigations 2014, Volume 2, Saskatchewan Geological Survey, Saskatchewan Ministry of the Economy, Miscellaneous Report , Paper A-8, 16p. Maxeiner, R.O., Rayner, N.M. and Creaser, R.A. (2015): Age and isotopic results from the La Ronge Horseshoe project: age of the Black Bear Island Lake inlier and provenance of sedimentary assemblages in the western Reindeer Zone; in Summary of Investigations 2015, Volume 2, Saskatchewan Geological Survey, Saskatchewan Ministry of the Economy, Miscellaneous Report , Paper A-8, 28p. Maxeiner, R.O., Rayner, N.M. and Eglington, B.M. (2012): U-Pb and Sm-Nd isotopic results from the La Ronge Horseshoe project area, western Glennie Domain and southern Rottenstone Domain: evidence for 2.22 to 2.52 Ga detritus; in Summary of Investigations 2012, Volume 2, Saskatchewan Geological Survey, Saskatchewan Ministry of the Economy, Miscellaneous Report , Paper A-10, 16p. Pinsent, R.H. (1980): Nickel-copper mineralization in the Lynn Lake Gabbro; Manitoba Department of Energy and Mines, Mineral Resources Division, Economic Geology Report ER79-3, 109 pages plus appendices. Sappin, A.-A., Constantin, M., Clark, T. and van Breemen, O. (2008): Geochemistry, geochronology, and geodynamic setting of Ni-Cu ± PGE mineral prospects hosted by mafic and ultramafic intrusions in the Portneuf-Mauricie Domain, Grenville Province, Quebec; Canadian Journal of Earth Sciences, v.46, p Stauffer, M.R. (1990): The Missi Formation: an Aphebian molasse deposit in the Reindeer Lake Zone of the Trans-Hudson Orogen, Canada; in The Early Proterozoic Trans-Hudson Orogen of North America, Lewry, J.F. and Stauffer, M.R. (eds.), Geological Association of Canada, Special Paper 37, p Stern, R.A. (1997): The GSC Sensitive High Resolution Ion Microprobe (SHRIMP): analytical techniques of zircon U-Th-Pb age determinations and performance evaluation; in Radiogenic Age and Isotopic Studies: Report 10, Geological Survey of Canada, Current Research 1997-F, p Stern, R.A. and Amelin, Y. (2003): Assessment of errors in SIMS zircon U-Pb geochronology using a natural zircon standard and NIST SRM 610 glass; Chemical Geology, v.197, p Stern, R.A., Lucas, S.B., Syme, E.C., Bailes, A.H., Thomas, D.J., Leclair, A.D. and Hulbert, L. (1993): Geochronological studies in the Flin Flon Domain, Manitoba-Saskatchewan, NATMAP Shield Margin Project area: results for ; in Radiogenic Age and Isotopic Studies: Report 7, Geological Survey of Canada, Paper 93-2, p Thomas, D.J. (1987): Bedrock geological mapping, Bing Lake area (part of NTS 73P-7 and -10); in Summary of Investigations 1987, Saskatchewan Geological Survey, Saskatchewan Energy and Mines, Miscellaneous Report 87-4, p Thomas, D.J. (1993): Geology of the Star Lake-Otter Lake Portion of the Central Metavolcanic Belt, La Ronge Domain; Saskatchewan Energy and Mines, Report 236, 132p. Turek, A., Woodhead, J. and Zwanzig, H.V. (2000): U-Pb age of the gabbro and other plutons at Lynn Lake (part of NTS 64C); in Report of Activities 2000, Manitoba Industry, Trade and Mines, Manitoba Geological Survey, p Van Schmus, W.R., Bickford, M.E., Lewry, J.F. and Macdonald, R. (1987): U-Pb zircon geochronology in the Trans-Hudson Orogen, northern Saskatchewan, Canada; Canadian Journal of Earth Sciences, v.24, p Wei, B., Yan Wang, C., Li, C. and Sun, Y. (2013): Origin of PGE-depleted Ni-Cu sulfide mineralization in the Triassic Hongqiling No. 7 Orthopyroxenite Intrusion, Central Asian Orogenic Belt, northeastern China; Economic Geology, v.108, p Saskatchewan Geological Survey 9 Summary of Investigations 2017, Volume 2