Saskatchewan Geological Survey 1 Summary of Investigations 2011, Volume 2

Interpretive Sub-Phanerozoic Mapping of the Deschambault High-resolution Aeromagnetic Survey Area

R.M. Morelli and D. Corrigan 1

Morelli, R.M. and Corrigan, D. (2011): Interpretive sub-Phanerozoic mapping of the Deschambault high-resolution aeromagnetic survey area; in Summary of Investigations 2011, Volume 2, Saskatchewan Geological Survey, Sask. Ministry of Energy and Resources, Misc. Rep. 2011-4.2, Paper A-9, 17p.

This report is accompanied by the map separate(s) entitled: Morelli, R.M. and Corrigan, D. (2011): Provisional interpretive map of sub-Phanerozoic geology, Deschambault Lake aeromagnetic survey (parts of NTS 63L/05, /06, /11, /12, /13 and 73I/07, /08, /09, /10, /15, and /16); 1:200 000-scale prelim. geological map with Summary of Investigations 2011, Volume 2, Saskatchewan Geological Survey, Sask. Ministry of Energy and Resources, Misc. Rep. 2011-4.2.

Abstract Work continued in 2011 on interpretive mapping of the sub-Phanerozoic extensions of the Flin Flon and Glennie domains. The 2011 project area coincides with that encompassing the Deschambault high-resolution aeromagnetic survey, flown in 2005, which extends ~30 to 50 km southward from exposed rocks of the southernmost Glennie Domain between Wapawekka and Deschambault lakes. The exposed Precambrian rocks are known locally to contain minor economic mineralization of varying styles, including volcanogenic massive sulphide Cu-Zn, magmatic Cu-Ni, and epigenetic gold. An objective of this project is to determine whether similar potential exists for the sub-Phanerozoic Precambrian rocks. Following the approach used in interpreting the sub-Phanerozoic basement of the eastern part of the project area in 2008-10 (the ‘core’ Flin Flon area), a number of geophysical ‘subdomains’ were delineated for the 2011 map area, each perceived to encompass rocks of contrasting magnetic/gravity signature relative to those of adjacent subdomains. The subdomains are lithologically characterized to the extent allowed by inspection of historic drillcore from the area, and have been broadly designated as being ‘intrusive-dominated’ (units Ga and Tn; Radar, Merritt, and Stanley subdomains), ‘supracrustal dominated’ (Meeyomoot, Oskikebuk, Dowd Creek, Deschambault, and Northern Lights subdomains) or of ‘unknown’ lithologic character (Nipekamew, Wuchewan, Puskwakua, and Tobin subdomains; unit FW). Several geophysical features are interpreted as deformational elements (fold, faults/shear zones), including the prominent ‘Dowd Creek shear zone’ of the Dowd Creek and northern Tobin subdomains. Consistent with interpretations of LITHOPROBE seismic data previously acquired in the area, this shear zone is thought to represent part of a major crustal detachment separating rocks of the Archean Sask Craton from overlying Paleoproterozoic allochthons.

Keywords: sub-Phanerozoic, Precambrian, Glennie Domain, Sask Craton, interpretive map, aeromagnetic, gravity, geophysical subdomain, drillcore.

1. Introduction In 2011, work continued on interpretive mapping of the sub-Phanerozoic extensions of Flin Flon and Glennie domain rocks. The Saskatchewan sub-Phanerozoic mapping project, initiated in 2008 within the Targeted Geoscience Initiative 3 (TGI-3) program, is running concurrently with sub-Phanerozoic mapping of the Flin Flon Domain in Manitoba (Simard and McGregor, 2009; Simard et al., 2010). The objective of the overall project is to provide an improved geological characterization of the Precambrian basement rocks to facilitate mineral exploration. The map boundary for the Saskatchewan project coincides with those of high-resolution aeromagnetic surveys flown over the area between 1985 and 2005. Between 2008 and 2010, sub-Phanerozoic mapping was focussed on the eastern portion of the overall map area (Morelli and MacLachlan, 2008; Morelli, 2009, 2010), extending approximately 90 km westward from the Manitoba border (‘core’ sub-Phanerozoic map area; Figure 1).

1 Natural Resources Canada, Geological Survey of Canada, 601 Booth Street, Ottawa, ON K1A 0E8.

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Figure 1 – Lithostructural domain map of the Precambrian Shield of Saskatchewan and study area of the sub-Phanerozoic project.

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Sub-Phanerozoic mapping in 2011 focussed on the western part of the project area, corresponding to the area of the Deschambault high-resolution aeromagnetic survey, flown in 2005 (Figure 1). In keeping with the format of the 2010 sub-Phanerozoic map of the ‘core’ area to the east (Morelli, 2010), mapping of the Deschambault survey area was accomplished by division of basement rocks into multiple ‘subdomains’ (Figure 2; see accompanying map, separate) based primarily on variations in geophysical character. Combined with previous mapping, this work provides a complete provisional interpretation of the sub-Phanerozoic geology for the map area. Field work in 2011 served to ‘ground-truth’ the geophysical interpretation and focussed on reconnaissance bedrock mapping along the Shield margin on Wapawekka and Deschambault lakes, as well as inspection of available drillcore from the map area housed at the Saskatchewan Ministry of Energy and Resources’ (SMER) La Ronge and Regina subsurface laboratories.

In the 2011 map area (Figure 2), the sub-Phanerozoic cover thickens southward from the Shield margin to a maximum of about 140 m at the southern map boundary. This cover includes up to 20 m of Quaternary glacial detritus, which overlies flat-lying Mesozoic and Paleozoic strata, most commonly of Cretaceous (Manville Group), Lower Ordovician (Red River and Winnipeg formations), and/or Cambro-Ordovician (Deadwood Formation) age (for descriptions see Saskatchewan Geological Survey, 2003). These sedimentary units are dominantly non-magnetic and do not obscure the magnetic signature of the underlying Precambrian rocks 2

2. Previous Sub-Phanerozoic Mapping

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In 1970, prior to acquisition of the high-resolution aeromagnetic data, an interpretation of the sub-Phanerozoic geology of the western portion of the 2011 study area was provided by geophysicist Franc Joubin (with accompanying report by Jan Klein; SMER Assessment File 73P10-0185; see inset on accompanying map separate). Inspection and interpretation of Phanerozoic and Precambrian drillcore in the map area, acquired in 1993-95 during kimberlite exploration by Consolidated Pine Channel Gold Corp./Mountain Province Mining Inc., was done by Gilboy (1995). The observations reported in that study were used, in part, for the present interpretation of the sub-Phanerozoic geology.

A provincial-scale interpretation of the sub-Phanerozoic Precambrian geology based on regional potential field geophysical maps was proposed by Kreis et al. (2000). According to this interpretation, the area under investigation in the present study was designated as parts of the ‘Wapawekka-Estevan’ and ‘Tobin’ domains. The Wapawekka-Estevan domain was interpreted to represent the manifestation of the collisional zone between dominantly juvenile rocks of the Reindeer Zone (north) and the buried Sask Craton (south), whereas the Tobin Domain was thought to represent strongly deformed, Archean-earliest Paleoproterozoic Sask Craton rocks (Saskatchewan Geological Survey, 2003).

Shortly after the Deschambault survey was flown in 2006, D. Corrigan presented a new interpretation of the subsurface geology of the survey area (Corrigan et al., 2006) based on the available geophysical data, observations from reconnaissance bedrock mapping on Wapawekka Lake, and inspection of drillcore from the survey area. This interpretation has been considered for, and partly integrated into, the map accompanying this report.

3. Methods/Available Information In addition to reconnaissance bedrock mapping of exposed rocks near the Shield margin, several sources of information were used for interpretation of the sub-Phanerozoic geology. The main source was publicly available geophysical data, particularly potential field (airborne magnetic and gravity) data available from Natural Resources Canada geophysical databases (Figure 3). The magnetic data from the Deschambault high-resolution airborne survey were acquired in the spring of 2006 using 400-m line spacing and at a flight altitude of 150 m above ground. The data were publicly released by the Geological Survey of Canada in July of 2006 and, for the present study, were interpreted using a variety of presentation techniques, including total-field magnetic intensity and several derivatives thereof (e.g., first vertical, horizontal, and tilt derivatives). Crustal-scale seismic reflection data were also available for the map area from two transects acquired between 1991 and 1994 during the LITHOPROBE program (e.g., White et al., 2005); line S2c provides a north-south transect through the western part of the map area, whereas a portion of line 9 provides an east-west transect through the central part of the map area (Figure 1). Interpretations of the combined geophysical data were tested by inspection of available drillcore, housed at the SMER subsurface laboratories in La Ronge and Regina. Information on drillcore no longer accessible/available was acquired by review of company drill logs. Additional information was gleaned from government assessment files.

2 Note that all Precambrian rocks discussed in this report have been metamorphosed and therefore the prefix ‘meta’ has been omitted from unit descriptions.

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Figure 2 – Interpreted sub-Phanerozoic geology of the Deschambault aeromagnetic survey area (see text/accompanying map separate for unit descriptions). Exposed rocks (north) labelled in black; buried rocks labelled in purple; and yellow diagonal hatching shows interpreted location of the extension of the Pelican thrust zone (basal detachment zone) in the map area. Abbreviations: CI = Churchman Island formation; NLA = Northern Lights assemblage; OLG = Oskikebuk Lake group; WL = Wapawekka Lake formation; WN = Wapawekka Narrows formation; VMS = volcanogenic massive sulphide; sz = D2 shear zone/tectonized rocks; and Hsz = Hartley shear zone. For simplification of the figure, the word subdomain has been omitted where applicable.

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Figure 3 – Potential field geophysical data for the 2011 map area, overlain by interpreted geophysical subdomains: A) shaded total-field magnetic data from the Deschambault airborne magnetic survey; and B) first vertical derivative of the Bouguer gravity anomaly. Potential field geophysical data from Natural Resources Canada (2011a, 2011b).

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Figure 4 – Outcrop photograph of dextrally rotated feldspar porphyroclast in sheared granodiorite, north-central Wapawekka Lake (UTM 531417 m E, 6090394 m N). Note: all UTM coordinates are in NAD83, zone 13 unless otherwise specified. Scale bar is in centimetres.

4. Geological Character of the Exposed Shield Mapping of exposed rocks to the immediate north of the Shield margin (i.e., the Wapawekka-Oskikebuk-Deschambault lakes area; Figure 2) was most recently completed by Government of Saskatchewan geologists (Padgham, 1966, 1967, 1968; Delaney, 1989, 1991). Reconnaissance mapping of exposed rocks in the sub-Phanerozoic map area in 2011 was guided by these maps and descriptions in the accompanying reports. Though more detailed rock descriptions and regional geological interpretations are available in these earlier reports, the geological character of the area can be broadly described as comprising a ‘granite-greenstone terrane’. Thin (2 to 10 km) east- to east-southeast–trending and moderately to gently northwest-dipping Paleoproterozoic supracrustal belts are bordered and intruded by extensive swaths of dominantly tonalitic-granodioritic-granitic plutons/plutonic complexes, mainly of successor arc derivation 3

Exposed supracrustal rocks in the map area have previously been subdivided into several different tectonostratigraphic groups/assemblages (Figure 2). In the easternmost part of the map area, the Northern Lights assemblage (NLA) is dominated by mafic volcanic and interlayered mafic and felsic volcaniclastic tuffs, and a stratigraphically overlying sequence of interlayered intermediate and felsic volcaniclastic rocks with minor siliceous (chert) and sulphidic intercalations (Maxeiner et al., 1999). A sequence of marine turbidites, probable equivalents of the widely exposed Burntwood Group in the Kisseynew Domain to the north, is exposed adjacent to volcanic rocks of the NLA.

. Several regional-scale, ductile high-strain zones transect the supracrustal belts and plutonic rocks near the margins of supracrustal belts. Though kinematic indicators are uncommon, a clockwise-rotated feldspar porphyroclast (Figure 4), observed this year on a horizontal outcrop surface of sheared rocks on northern Wapawekka Lake (Figure 2), indicates that at least some of these shear zones have undergone a component of dextral movement.

Further to the west, the ‘Oskikebuk Lake group’ (OLG; Padgham, 1968) defines a belt extending from Fisher Bay on Deschambault Lake northwest and westwards towards the east end of Wapawekka Lake (Figure 2). The OLG (Figure 5) is dominated by aphyric and plagioclase-phyric, hornblendic mafic volcanic rocks, locally containing calc-silicate layers, and mafic volcaniclastic rocks. Rare exposures of intermediate volcanic, felsic volcanic, and siliciclastic sedimentary rocks have also been reported.

In the Wapawekka Lake area, supracrustal sequences have been collectively termed the Wapawekka group (Padgham, 1967), which is further subdivided into three formations: the Wapawekka Narrows, Churchman Island, and Wapawekka Lake formations. The Wapawekka Narrows formation (e.g., Figures 6A and 6B) consists mainly of mafic to intermediate volcanic rocks, including amygdaloidal, plagioclase-phyric and rare pillowed varieties, and mafic to intermediate tuffs and tuff breccias. Subordinate rock types include mafic to intermediate, possibly

synvolcanic, intrusions, and soapstone that is probably derived from ultramafic intrusions. The Churchman Island formation (CI) is dominated by interlayered mafic, intermediate and felsic tuffs, siliciclastic sedimentary rocks, and mafic to intermediate flows and conformable intrusions (e.g., Figures 6C and 6D). The original stratigraphic relationship between rocks of the Wapawekka Narrows and Churchman Island formations has not been resolved. The Wapawekka Narrows/Churchman Island formations are unconformably overlain by rocks of the Wapawekka Lake formation, which consists mainly of arkose, quartz grit sandstone and polymictic conglomerate (e.g., Figure 6E), with minor tuffaceous intercalations. A distinctive magnetite-bearing, hornblende porphyroblastic mafic-ultramafic sill (Figure 6F) presumably intrudes the siliciclastic rocks and is manifest as a strong magnetic anomaly that straddles much of northern Wapawekka Lake and is interpreted to extend towards the southwest beneath the Phanerozoic cover (unit GaHS; Figure 3).

3 Use of the term “successor” throughout this report refers to rocks formed after intra-oceanic accretion, following usage by Syme et al. (1998), i.e., intrusive rocks emplaced between ca. 1880 and 1840 Ma.

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Figure 5 – Outcrop photos of volcanogenic rocks of the Oskikebuk Lake group on Deschambault Lake: A) typical aphyric, hornblende-rich mafic volcanic rock (UTM 590106 m E, 6066322 m N); B) plagioclase-phyric mafic volcanic rock (UTM 593367 m E, 6067590 m N); and C) calc-silicate–rich layers in highly strained, compositionally heterogeneous mafic to intermediate volcanic/volcaniclastic rocks (UTM 589649 m E, 6070873 m N).

The supracrustal belts are intruded by widespread plutons of varying size and composition, the majority having been emplaced during ca. 1870 to 1840 Ma successor arc magmatism (e.g., Syme et al., 1998). Some felsic- to intermediate-dominated constituents underlie extensive expanses of the map area (Figure 2), such as the Ballantyne Bay tonalite that surrounds much of Deschambault Lake, the Radar Bay/Jira Lake tonalitic–granodioritic–quartz dioritic complex on southern Wapawekka Lake, and the Folkerson Lake granodiorite batholith on the north shore of Wapawekka Lake. Similarly, the Oskikebuk quartz diorite gneiss, which underlies much of the area between Oskikebuk and Deschambault lakes, is an extensive plutonic complex, although it has been subjected to elevated metamorphic conditions and increased deformational stress relative to many other intrusive bodies. A suite of intermediate-mafic-ultramafic intrusions, including the Signal Bay mafic-ultramafic complex on western Wapawekka Lake and an isolated pyroxenitic pluton near West Arm of Deschambault Lake, represent a distinct and relatively late plutonic suite commonly manifest as magnetic and gravity highs.

All supracrustal rocks and the majority of plutonic rocks in the exposed part of the map area are polydeformed and metamorphosed. Deformational and metamorphic textures observed in these rocks during reconnaissance mapping and outlined in previous reports (e.g., Padgham, 1967, 1968; Delaney, 1989, 1991) can generally be related to the four-fold deformational history proposed for the Reindeer Zone by Lewry et al. (1990). This model related early structures (D1/D2) to a crustal shortening event caused by the emplacement of extensive allochthons of juvenile, originally intra-oceanic rocks over top of the Sask Craton. In rocks of the present map area, defined as part of the ‘Cartier Sheet’ (ibid), this tectonic event likely produced the main, dominantly east-west–trending and steeply north-dipping foliation and co-planar isoclinal folds (Figure 7A). Several prominent, east- to southeast-trending and steeply north-dipping, ductile shear zones (e.g., the ‘Hartley’ shear zone; Delaney, 1989; Figure 2) and related structures were also produced at this time (Figures 7B and 7C). Peak metamorphic mineral assemblages in the area, which range from lower to upper amphibolite facies, were probably also produced at this time. Originally flat-lying structures related to nappe emplacement were refolded during subsequent post-collisional, oblique convergence (D3 and D4 events). The D3 deformation event is now manifest in the map area as mesoscopic to macroscopic, north-northwest– to north-northeast–trending upright folds (F3; Figure 7D) with an associated axial-planar crenulation cleavage, as well as north–trending, steeply dipping ductile shears and brittle faults. The D4 event, in turn, resulted in refolding of all earlier structures into northeast-plunging, upright, tight to open regional folds that collectively form an orogen-wide, northeast-plunging anticlinorium (Lewry et al., 1990). Subsequent protracted movement within the continent was, in part,

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Figure 6 – A) Fine-grained mafic dyke cutting plagioclase-phyric mafic volcanic rock, Wapawekka Narrows Formation (UTM 547715 m E, 6090989 m N); B) mafic to intermediate tuff breccia, Wapawekka Narrows Formation (UTM 538248 m E, 6087451 m N); C) thin garnetiferous pelitic interlayers in psammopelite, Churchman Island Formation (UTM 541337 m E, 6089863 m N); D) interlayered felsic/intermediate tuff, Churchman Island Formation (UTM 538826 m E, 6091054 m N); E) large siliceous clast in matrix-supported, polymictic conglomerate, Wapawekka Lake Formation (UTM 545428 m E, 6091145 m N); and F) hornblende porphyroblastic mafic-ultramafic sill intruding conglomerate/arkose of the Wapawekka Lake Formation (UTM 541309 m E, 6091234 m N).

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Figure 7 – Characteristic structural features of the Wapawekka-Deschambault lakes area: A) foliation-parallel (syn-D2?) isoclinal folds (e.g., white dotted line represents S1) in mafic volcanic rocks, Deschambault Lake (UTM 588037 m E, 6069779 m N); B) highly strained and boudinaged tonalite in (D2) shear zone, western Deschambault Lake; arrows point to boudin necks (UTM 589090 m E, 6070696 m N); C) inclusions of dismembered granitic vein (arrows) in D2 shear zone, east-central Wapawekka Lake (UTM 543934 m E, 6089999 m N); and D) close D3 kink folds (e.g., black dotted line) refolding D2 foliation in mafic volcanic rocks, Deschambault Lake (UTM 589703 m E, 6069114 m N).

accommodated by late regional strike-slip faults, most notably those in the Tabbernor fault zone (Figure 1).

5. Subdivisions of Sub-Phanerozoic Rocks Mapping of sub-Phanerozoic Precambrian rocks in the Deschambault aeromagnetic survey area was done using the same approach as that for the eastern part of the sub-Phanerozoic map area in 2010 (see Morelli, 2010). Specifically, several geophysical ‘subdomains’ were delineated, each encompassing rocks of similar magnetic character and are, in places, bound by magnetic features interpreted as faults/shear zones. Variations in rock density were also considered in designating subdomain boundaries in some cases. Observations from drillcore and available assessment file information were used to provide a preliminary lithological characterization of the underlying rocks, though individual subdomains can contain multiple rock types and, in many cases, lithologic units probably cross boundaries between adjacent subdomains. Particularly noteworthy for the 2011 map area is the relative paucity of historic drilling (<30 accessible holes for the >4500 km2 area), requiring increased dependence on the geophysical data for interpretation.

Brief synopses of each of the geophysical subdomains interpreted for the Deschambault aeromagnetic survey are provided below (refer to Figure 2 and accompanying map separate).

a) Intrusive Rock-dominated Tonalite (Tn): This unit is characterized by rocks having generally moderate intensity and vaguely defined magnetic signatures, and low to moderate densities. They are interpreted to consist dominantly of intermediate to

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Figure 8 – Coarse-grained, massive pyroxenite, drillhole Pine Channel Oskikebuk River Kimberlite 13B (UTM 561094 m E, 6074125 m N; represents approximate drillhole collar location.

felsic, medium- to coarse-grained plutons, or gneissic equivalents, and can comprise both extensive granitoid terranes (i.e., similar to the exposed Folkerson Lake and Ballantyne Bay batholiths) and smaller isolated intrusions. These rocks are likely successor arc derived. Specific examples include unit TnBB, interpreted as the sub-Phanerozoic extension of the Ballantyne Bay tonalite.

Gabbro/Pyroxenite (Ga): Characterized by gravity highs and high amplitude magnetic anomalies, this unit is interpreted to represent magnetite-bearing mafic-ultramafic intrusions (e.g., Figure 8) comprising small isolated intrusions within some of the subdomains, extensive sills/dykes (e.g., unit GaHS) and/or intrusive complexes (e.g., unit GaWIC). Unit GaHS is interpreted as a hornblende porphyroblastic, layered mafic-ultramafic sill, equivalent to that exposed on northern Wapawekka Lake (Figure 6F). The magnetic signatures of this unit commonly do not conform to the dominant structural fabrics in adjacent rocks (i.e., post-date these fabrics?), though some exceptions are apparent. Gravity highs caused by these intrusions commonly obscure the true gravity signature of the host rocks. These rocks are thought to be the geophysical equivalent of unit Ga in the core sub-Phanerozoic map area to the east (Morelli, 2010).

Radar subdomain (Rsdm): Defined mainly by extrapolation of geophysical attributes of exposed rocks into the subsurface, this unit is interpreted as the probable extension of the exposed Radar Bay/Jira Lake intrusive complex. By analogy with the exposed equivalent, the unit comprises dominantly leucocratic tonalite and granodiorite, with subordinate phases of diorite, quartz diorite, quartz monzonite, and granite. The rocks are dominantly equigranular, but porphyritic phases are known locally. They are probably petrogenetically similar (equivalent?) to unit Tn, but are designated as a distinct unit due to the higher degree of confidence in the interpretation owing to its position immediately adjacent to the Shield margin. These plutonic rocks are likely derived predominantly from successor arc magmatism.

Merritt subdomain (MRsdm): Two known drill intersections into rocks of this subdomain, distinguished by the strong northeast trend of magnetic anomalies relative to adjacent rocks, yielded granite and granitic gneiss, mafic gneiss, and quartz diorite. Minor crosscutting tonalitic veins were also identified. A shear zone with gradational boundaries was identified in one drillhole (Pine Channel; #70A; Gilboy, 1995) in which it separates coarse-grained equigranular granite from underlying mafic gneiss. The gneissic textures and/or shear fabrics inherent to rocks of this subdomain likely impart its characteristic northeast-trending magnetic fabric.

Stanley subdomain (Ssdm): This subdomain is characterized by a low-density signature and a strong northeasterly trending, linear magnetic fabric. The rocks are likely dominated by granodioritic and granitic gneisses, partly an extension of the exposed Folkerson Lake batholith. Minor hornblende gneisses, quartz diorite, and tonalite are also present. The plutonic rocks are likely of successor arc derivation. The strong northeast-trending magnetic fabric likely represents a transposed foliation along the southwestern extension of the exposed Stanley fault zone (see Lewry et al., 1990).

b) Supracrustal Rock-dominated Meeyomoot subdomain (MTsdm): This subdomain is characterized by linear, moderate- to high-amplitude, northeast-trending magnetic anomalies on the northwest margin of two gravity highs. It is considered to represent the sub-Phanerozoic extension of the exposed, supracrustal rock-dominated Wapawekka group. It is likely dominated by mafic to intermediate volcanic/volcaniclastic/intrusive rocks of the Wapawekka Narrows and Churchman Island formations, but might also contain siliciclastic sedimentary rocks, including polymictic conglomerate, arkose, and greywacke of the Wapawekka Lake formation. Subordinate felsic volcanic/volcaniclastic rocks might also be present. This subdomain hosts the Wert Lake Zn-Cu zone (Saskatchewan Mineral Deposit Index (SMDI) #2748) and DWP Cu zone (SMDI #2749) occurrences and the Great Plains of Wapawekka Drillhole No. 1 mineral location (SMDI #0672).

Oskikebuk subdomain (Osdm): Although no known drillholes have intersected these rocks, the continuation of the moderate to high amplitude, linear magnetic anomalies associated with exposed mafic volcanic rocks of the Oskikebuk Lake group were interpreted as the continuation of this sequence into the subsurface. As such, it is

Saskatchewan Geological Survey 11 Summary of Investigations 2011, Volume 2

Figure 9 – Drillcore intersections of sedimentary rocks of the Dowd Creek subdomain: a) strongly foliated, pyritic and graphitic pelite, drillhole Pine Channel Deschambault Lake Kimberlite 23A (566889 m E, 6063635 m N); and b) interlayered oxide-facies (‘OF’) and silicate-facies (‘SF’) iron formation and chert (‘CH’), drillhole SELCO 69-6 (UTM 584530 m E, 6057739 m N).

interpreted to be underlain mainly by mafic to intermediate volcanic flows, locally plagioclase-phyric and/or amygdaloidal, as well as mafic volcaniclastic rocks, mafic wacke, and hornblende-plagioclase gneiss/schist.

Dowd Creek (DCsdm): Rocks of this subdomain are dominantly non- to weakly magnetic except for a few isolated, moderate-intensity, west-trending anomalies. The clockwise-rotated and attenuated appearance of some of these isolated anomalies, and several of those along the subdomain margins, suggest that rocks of the Dowd Creek subdomain have experienced a significant component of shear, at least some of which had a dextral component. A significant ductile shear zone (the ‘Dowd Creek shear zone’; Figure 2) is interpreted accordingly. The few available drill intersections indicate a dominance of siliciclastic sedimentary rocks in this subdomain, mainly comprising psammite, psammopelite and calcic psammopelite, sulphidic and graphitic pelite (Figure 9A), and localized interlayers of oxide- and silicate-facies banded iron formation (Figure 9B). Subordinate mafic volcanic/volcaniclastic rocks and diorite are also present. The sequence has been intruded by multiple mafic to ultramafic intrusions (unit Ga).

Deschambault subdomain (Dsdm): Multiple drillhole intersections clustered in the westernmost portion of the subdomain, which is characterized by dominantly non- to weakly magnetic rocks, indicate a significant component of siliciclastic sedimentary rocks. The observed sequence in drillcore contains dominantly melt-bearing (migmatized) pelite/paragneiss (Figure 10), locally garnet- and/or cordierite-bearing and partly graphitic and/or pyritic, with subordinate psammitic interlayers. These sedimentary rocks might correlate, in part, with those of the adjacent Deschambault subdomain, though no information on depositional age or provenance of sedimentary rocks for either subdomain is currently available. Notwithstanding the prevalence of siliciclastic sedimentary rocks in

drillcore, the high-density character and the presence of multiple linear, moderate- to high-amplitude magnetic anomalies, particularly in the northwestern extension of the subdomain, suggest the presence of a significant mafic component, possibly volcanic. The apparent non-magnetic signature of the southern part of the subdomain is probably an artifact reflecting its location adjacent to strongly magnetic rocks (e.g., unit Ga, FW).

Northern Lights subdomain (NLsdm): The Northern Lights subdomain, continuous across the western boundary of the 2010 sub-Phanerozoic map area (Morelli, 2010), is considered the probable extension of the exposed, mafic to intermediate volcanic-dominated Northern Lights assemblage. The constituent rocks exhibit north-trending, moderate- to high-intensity magnetic anomalies, some of which appear to define tight to isoclinal fold closures. The subdomain contains abundant mafic to intermediate volcanic/volcaniclastic rocks with subordinate felsic volcanic/volcaniclastic rocks (Figure 11). Subvolcanic felsic porphyritic intrusions, minor oxide-facies banded iron formation,

Figure 10 – Garnetiferous migmatized pelite with foliation-parallel tonalitic leucosome, Deschambault Lake subdomain, drillhole Pine Channel Deschambault Lake Kimberlite 72A (UTM 568844 m E, 6055131 m N).

SF

CH

OF

A

B

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Figure 11 – Drillcore photographs of volcanogenic rocks of the Northern Lights subdomain: a) aphyric to plagioclase-phyric mafic volcanic rocks, drillhole BS-40 (UTM 618211 m E, 6051814 m N); b) feldspar-phyric dacite (intrusion?), drillhole BS-40 (UTM 618211 m E, 6051814 m N); and c) chalcopyrite stringers in dacite from the Bigstone Lake Zn-Cu deposit, drillhole BS-3 (UTM 616392 m E, 6048426 m N); arrows highlight some chalcopyrite stringers.

and graphitic schists are also present, and the supracrustal sequence is cut by granitic to granodioritic and mafic/ultramafic intrusions. Rocks of this subdomain host the Bigstone Lake Zn-Cu deposit/Kelsey Au occurrence (SMDI #1779; Figure 11C), Freeport Zn showing (SMDI #2215), Twigge Lake Cu showing (SMDI #2703), and several minor Zn-Cu or Mo occurrences.

c) Unknown Lithological Character Wuchewan subdomain (WNsdm): Characterized by rocks exhibiting a dominantly low-density, weakly to moderately magnetic geophysical signature, this subdomain is undrilled and the lithologic makeup is unknown. Based, however, on similarities in magnetic intensity with unit TnBB to the immediate east (Figure 3), rocks of this subdomain are likewise interpreted as being dominantly felsic orthogneisses and/or felsic plutonic rocks. In contrast to the largely non-textured magnetic signature of unit TnBB, the readily apparent linear form and strong northeast trend of anomalies in the Wuchewan subdomain are interpreted to reflect an elevated strain state in these rocks.

Nipekamew subdomain (NPsdm): This subdomain is characterized by rocks of low to moderate magnetic intensity, with the exception of one moderate to high intensity, northeast-trending anomaly that appears to define a large isoclinal fold closure (feature ‘M1’ on Figure 3A). The dominant lithologic makeup is uncertain, with the two known drill intersections yielding chloritized gabbro and fine-grained, homogenous quartz monzonite. The constituent rocks could be partly contiguous with supracrustal rocks of the adjacent Meeyomoot subdomain or with presumed orthogneisses of the adjacent Wuchewan subdomain. Alternatively, they could represent, in part, the possible extension of a chemical and clastic-sedimentary rock-dominated sequence intersected by Golconda Resources’ 1999 drillholes DEL-2 and -4 (SMER Assessment File 73I11-NE-0004) ~6.5 km outside of the present map area to the immediate west (Figure 2). The intersected sequence includes extensive oxide-facies banded iron formation, ferruginous mudstone, quartzofeldspathic clastic sedimentary rocks, and felsic crystal tuffs (Figure 12).

Puskwakua subdomain (Psdm): This subdomain is dominated by weakly to moderately magnetic rocks, the structural position and lithologic makeup of which are unknown. The only known drillhole intersected a weakly to moderately foliated, coarse-grained gabbroic to dioritic intrusion. The subdomain is tentatively interpreted to represent rocks forming a relatively thin veneer of (sheared?) Paleoproterozoic rocks overlying older (footwall) rocks of the Tobin subdomain of the Sask Craton.

Tobin subdomain (Tsdm): This subdomain is equivalent to the northern part of the Tobin domain, as defined by Kreis et al. (2000). It exhibits multiple high-intensity, linear magnetic anomalies, commonly arcuate, that define isoclinal folds and fold interference

A

B

C

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Figure 13 – Major structural features of the Trans-Hudson Orogen in Saskatchewan (from Lewry et al., 1994). Abbreviations: PTZ = Pelican thrust zone; NA = Nunn Lake antiform; and DS = Deschambault Lake synform.

Figure 12 – Isoclinally folded oxide-facies banded iron formation from Golconda Resources drillhole DEL-4 (see Figure 2 for location; UTM 493578 m E, 6056956 m N).

patterns. The main magnetic fabric of the subdomain differs from that of subdomains to the north, except along its northernmost margin where the fabric is parallel to that of rocks of the adjacent Dowd Creek subdomain. Consistent with the interpretation of LITHOPROBE Line S2c (Hajnal et al., 2005), the magnetic fabric along the northernmost margin of the Tobin subdomain probably reflects the effects of the Dowd shear zone. The subdomain is interpreted to comprise Archean to earliest Paleoproterozoic rocks of the Sask Craton. The only two known drill intersections are ~100 km to the southeast and yielded upper amphibolite to granulite facies pelitic gneiss with a Nd depleted mantle model age of ca. 3.04 Ga (Collerson et al., 1988).

Footwall (FW): These geophysically distinct features, confined to the Puskwakua subdomain, are characterized by diffuse and poorly defined magnetic anomalies that appear to partly overlap with shorter wavelength anomalies similar to those present in the northern Puskwakua subdomain (e.g., features ‘M2’;

Figure 3A). This magnetic texture is interpreted to derive from the obstruction of deeply sourced magnetic bodies, possibly contiguous with highly magnetic rocks of the Tobin subdomain, by overlying weakly magnetic rocks of the Puskwakua subdomain. The lithologic character of the rocks responsible for these features is unknown. It is possible that the geophysical expressions interpreted as the ‘FW’ unit are visible because the source rocks occupy structural culminations that caused localized steepening of the regional fabric (i.e., upright, north-northwest– to north-northeast–trending anticlinal hinges of regional (?F3) folds).

6. Lithostructural/Tectonic Context of Sub-Phanerozoic Rocks Interpretation of seismic reflection data from LITHOPROBE lines 9 (Lewry et al., 1994; Pandit et al., 1998) and S2c (Hajnal et al., 2005) provide a first-order representation of the crustal architecture in the Deschambault survey area. The LITHOPROBE interpretations outline a north-trending, crustal-scale, anticlinal culmination running through the northwestern extreme of the survey area (i.e., near the axial trace of the Nunn Lake antiform; Figure

13). This culmination is cored by the buried Sask Craton (i.e., the ‘crustal root’) that is, in turn, structurally overlain by a series of allochthons comprising strongly reflective juvenile Paleoproterozoic rocks (Reindeer Zone), including mylonitic sole thrusts. West of the culmination, the overall crustal stack dips to the west, whereas it dips eastwards to the east of the culmination. The thrust/mylonite zones at the base of individual nappes, including both the basal detachment zone between Archean (Sask Craton) footwall and overlying allochthonous Paleoproterozoic rocks (i.e., the ‘Pelican thrust zone’; Ashton et al., 2005) and splays off of this zone (e.g., the Hartley shear zone; Hajnal et al., 2005), are imaged as a distinct set of shallowly dipping, strong reflectors (e.g., Pandit et al., 1998).

RottenstoneDomain

La RongeDomain

KisseynewDomain

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ch R

apid

s sh

ear

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st

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y fa

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rgeo

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eir

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2011 sub-Phanerozoic map area

Proterozoic ductile shear zone (D2; i.e., Pelican thrust zone and equivalents) D3 fold trace

D4 fold trace

D2 shear zoneArchean inlier

late (reactivated?) brittle fault

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An implication of the LITHOPROBE interpretations is that the extension of the Pelican thrust zone – the main basal detachment zone – should subcrop in the 2011 map area. This is consistent with the magnetic expression for that area (e.g., Kreis et al., 2000), which appears to be centred on the contact between the largely buried Sask Craton and the structurally overlying Paleoproterozoic allochthons. The dominant east-west structural/magnetic fabric of the map area was likely produced during the regional deformation event that caused overthrusting of Paleoproterozoic allochthons over the Sask Craton margin (i.e., D2; Lewry et al., 1990). The geophysical expression of the Pelican thrust zone, as well as splays off of this zone, should therefore broadly parallel this fabric. Based on the preliminary interpretation of sub-Phanerozoic rocks presented herein, highly strained rocks of the Dowd Creek subdomain and, perhaps, those of the northernmost Tobin subdomain represent the most likely location of the subcropping detachment zone in the western part of the map area. The boundaries of this detachment zone are less obvious in the magnetic data for the eastern part of the map area. Rocks of the eastern Dowd Creek subdomain also appear sheared from the magnetic data, though it is currently unclear from existing information whether this major shear zone also subcrops to the south within rocks of the Puskwakua and/or Deschambault subdomains. In terms of lithostructural character and tectonic significance, the rocks of the Paskwakua and Deschambault subdomains remain perhaps the largest uncertainty of the 2011 map area. It is currently unclear whether some or all of these rocks represent part of the Sask Craton or part of the juvenile Paleoproterozoic allochthonous cover and, contingent on this uncertainty, to what degree they have been affected by shearing along the contact between the two tectonic entities. An alternative possibility is that the rocks are relatively unaffected by shearing along this main detachment zone and, at least in part, represent an autochthonous sedimentary-dominated cover sequence that stratigraphically overlies older Sask Craton rocks (i.e., an analog to the Ospwagan and Wollaston groups on the Superior and Hearne Craton margins, respectively; see Ansdell, 2005). A more definitive characterization of this part of the sub-Phanerozoic map area requires further analytical work on existing drillcore, enhanced and/or additional geophysical data and, perhaps, additional drilling.

The early (D2), originally sub-horizontal shear zones and related structures were reoriented and, in some cases, considerably steepened during post-collisional intracontinental deformation (D3 and D4 structures; Lewry et al., 1990). Some such structures are known in exposed rocks of the 2011 map area, including major (Nunn Lake antiform, Deschambault Lake synform; Figure 13) and minor (e.g., Lacey/Kidd lakes folds; Maynard Lake anticline; Padgham, 1968) D3 folds, and regional northeast-trending D4 cross folds (Figure 13). Outcrop-scale examples of late folds and related fabrics, particularly of the D3 generation, are widespread throughout the map area and were commonly observed during reconnaissance mapping in 2011 (e.g., Figure 2). Some examples of coeval (D3) north-trending folds are interpreted to affect the sub-Phanerozoic rocks (e.g., folding of FW unit; Figure 2). In contrast, however, to the late, dominantly north-trending structural overprint of rocks underlying much of the sub-Phanerozoic map area to the east of the late, brittle Tabbernor fault zone (Morelli, 2010), rocks of the 2011 map area exhibit a relatively minor D3/D4 overprint and dominantly maintain the east-west trend interpreted to have originated during D2 deformation. This is perhaps due to the fact that rocks in this area were sheltered from intracontinental deformation during post-collisional deformation due to the sheltering effects of the intervening Sask Craton (i.e., provided a ‘strain shadow’). Recognition of this variation in structural pattern has important implications for interpretation of the sub-Phanerozoic rocks, particularly regarding continuity of mineralized greenstone belts across the Tabbernor fault zone.

7. Economic Mineral Potential Relative to rocks of the 2010 sub-Phanerozoic map area to the east, rocks underlying the 2011 map area contain far fewer known economic mineral occurrences. It is unclear at this point, however, to what degree this reflects an inherent difference in economic potential of the rocks in the two areas as opposed to the degree to which the two areas have been explored. Notwithstanding this disparity, which will be a focus of ongoing study, Precambrian rocks of the 2011 map area have known potential for multiple types of economic mineralization (Figure 2). A brief synopsis is provided below.

Volcanogenic massive sulphide (VMS)-style Cu-Zn±Pb±Au mineralization is known in exposed greenstone belts throughout the area, and sub-Phanerozoic examples are currently known in the Northern Lights and Meeyomoot subdomains (Figure 2). Potential for this type of mineralization in the subsurface exists almost exclusively within subdomains interpreted to contain volcanic rocks; in addition to the Northern Lights and Meeyomoot subdomains, the Oskikebuk subdomain and possibly parts of the Deschambault subdomain also hold potential for VMS-style mineralization.

Minor occurrences of structurally controlled (i.e., ‘orogenic’) gold mineralization are known in exposed rocks on the northern shore of Fisher Bay on Deschambault Lake, near Alsmith Lake, and at the easternmost end of Wapawekka Lake (Figure 2). In these areas and elsewhere in the Glennie Domain (see Delaney, 1992), this style of gold mineralization is known mainly in subsidiary splays off of major shears (e.g., Hartley shear zone), particularly within and on the margins of greenstone belts. There are currently no known examples of this style of gold

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mineralization in the buried rocks, though potential exists in proximity to interpreted D2 shears (e.g., the Dowd Creek shear zone).

Magmatic (mafic/ultramafic intrusion-hosted) Cu-Ni mineralization occurrences and talc occurrences associated with these intrusions are known in exposed rocks on eastern Wapawekka Lake and east of Deschambault Lake, near the easternmost boundary of the map area. The only known sub-Phanerozoic example of this type is a drill intersection of disseminated pyrite and chalcopyrite hosted by a gabbroic-ultramafic intrusion (DWP Cu Zone; SMDI #2749). In the sub-Phanerozoic rocks, the most potential for this style of mineralization exists where mafic-ultramafic intrusions have been interpreted (i.e., unit ‘Ga’). Specific examples could include the Wapawekka intrusive complex (GaWIC) and the compositionally layered, hornblende porphyroblastic, mafic-ultramafic sill on the northwestern Meeyomoot subdomain margin (unit GaHS), which extends into exposed clastic sedimentary rocks of the Wapawekka Lake formation on northern Wapawekka Lake. Intrusion of such magmas into siliciclastic sedimentary rocks can represent a particularly favourable situation due to the possibility that these host rocks can provide a source of sulphur for promotion of Ni-Cu sulphide formation. As such, sub-Phanerozoic mafic-ultramafic intrusions within the Dowd Creek and Deschambault subdomains, which are also known to contain clastic sedimentary rocks, could hold potential for mineralization.

Kimberlite exploration has been undertaken sporadically throughout the map area. Although no kimberlites have been located to date, the presence of known diamondiferous kimberlites in the Fort à la Corne area, located approximately 130 km to the south and similarly underlain by the Sask Craton crustal root, suggests that there may be potential for diamondiferous kimberlites in this area.

8. Summary and Future Work Sub-Phanerozoic Precambrian rocks underlying the Deschambault aeromagnetic survey area have been subdivided into multiple geophysical subdomains, the boundaries of which were delineated primarily from perceived variations in the magnetic and/or density signature of adjacent subdomains. These subdomains were then lithologically characterized, to the extent allowable by availability of existing drillcore and of historical drilling/exploration records. Subdomains were designated as being either intrusive rock–dominated (Radar, Merritt, and Stanley subdomains; units ‘Ga’ and ‘Tn’) or supracrustal rock-dominated (Meeyomoot, Oskikebuk, Dowd Creek, Deschambault, and Northern Lights subdomains). Subdomains from which insufficient information exists to characterize the contained rocks are designated as having ‘unknown lithological character’ (e.g., Nipekamew, Wuchewan, Puskwakua, and Tobin subdomains and unit ‘FW’).

Using seismic and potential field data, the 2011 sub-Phanerozoic map area has been previously interpreted to encompass the transition between allocthonous Paleoproterozoic nappes and underlying footwall rocks of the Sask Craton. Following this interpretation and using the nomenclature presented herein, this detachment zone is interpreted to be situated within the Dowd Creek subdomain and might also incorporate parts of the northernmost Tobin subdomain and/or the Deschambault and/or Puskwakua subdomains. Post-collisional (regional D3 and D4) structures are also interpreted for the sub-Phanerozoic rocks.

Future work on this portion of the greater sub-Phanerozoic project map area will involve: (i) providing a lithogeochemical and isotopic characterization of both exposed and buried supracrustal rocks; (ii) temporal characterization of selected rock units through geochronological studies; and (iii) further interpretation of the three-dimensional geometry of this part of the Trans-Hudson Orogen.

9. Acknowledgements Robert Fischbuch provided excellent field and office assistance for this project during the summer of 2011. Thomas Love is thanked for providing GIS expertise in the generation of the accompanying 1:200 000-scale map. Mark Pilkington (Geological Survey of Canada) produced some of the presentations of aeromagnetic data used for interpretation of the sub-Phanerozoic geology. Natalie Thompson and Richard Wood are thanked for facilitating core inspection at the La Ronge and Regina subsurface laboratories, respectively. Sean Bosman and Ken Ashton provided insightful internal reviews of the original draft of this report.

10. References Ansdell, K.M. (2005): Tectonic evolution of the Manitoba-Saskatchewan segment of the Paleoproterozoic Trans-

Hudson Orogen, Canada; Can. J. Earth Sci., v42, no4, p741-759.

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Ashton, K.E., Lewry, J.F., Heaman, L.M., Hartlaub, R.P., Stauffer, M.R., and Tran, H.T. (2005): The Pelican Thrust Zone: basal detachment between the Archean Sask Craton and Paleoproterozoic Flin Flon–Glennie Complex, western Trans-Hudson Orogen; Can. J. Earth Sci. v42, no4, p685-706.

Collerson, K.D., Van Schmus, R.W., Lewry, J.F., and Bickford, M.E. (1988): Buried Precambrian basement in south-central 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, p142-150.

Corrigan, D., Pilkington, M., and Kiss, F. (2006): The Deschambault high-resolution aeromagnetic survey: towards a new interpretative geological map; Open House 2006, Saskatchewan Geological Survey, Abstr. Vol., p27.

Delaney, G.D. (1989): Bedrock geological mapping, Maynard-Wapawekka lakes area (part of NTS 73I-16, 63L-13, 63M-3 and 73P-1); in Summary of Investigations 1989, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 89-4, p17-27.

_________ (1991): Revision bedrock geological mapping, Deschambault-Oskikebuk lakes area (parts of NTS 73I-16, 63L-11, -12, -13, and -14); in Summary of Investigations 1991, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 91-4, p47-56.

__________ (1992): Gold in the Glennie Domain; Sask. Energy Mines, Misc. Rep. 92-5, 71p.

Gilboy, C.F. (1995): Stratigraphic data from selected kimberlite exploration core, northeastern central Saskatchewan; in Summary of Investigations 1995, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 95-4, p109-116.

Hajnal, Z., Lewry, J., White, D., Ashton, K., Clowes, R., Stauffer, M., Gyorfi, I., and Takacs, E. (2005): The Sask Craton and Hearne Province margin: seismic reflection studies in the western Trans-Hudson Orogen; Can. J. Earth Sci., v42, no4, p403-419.

Kreis, L.K., Ashton, K.E., and Maxeiner, R.O. (2000): Geology of the Precambrian basement and Phanerozoic strata in Saskatchewan: Sheet 1 of 8, Lower Paleozoic Map Series; Sask. Energy Mines, Misc. Rep. 2004-8.

Lewry, J.F., Hajnal, Z., Green, A., Lucas, S.B., White, D., Stauffer, M.R., Ashton, K.E., Weber, W., and Clowes, R. (1994): Structure of a Paleoproterozoic continent-continent collision zone: a LITHOPROBE seismic reflection profile across the Trans-Hudson Orogen, Canada, Tectonophys., v232, p143-160.

Lewry, J.F., Thomas, D.J., Macdonald, R., and Chiarenzelli, J. (1990): Structural relations in accreted terranes of the Trans-Hudson Orogen, Saskatchewan: telescoping in a collisional regime?; in Lewry, J.F. and Stauffer, M.R. (eds.), The Early Proterozoic Trans-Hudson Orogen of North America, Geol. Assoc. Can., Spec. Pap. 37, p75-94.

Maxeiner, R.O., Sibbald, T.I.I., Slimmon, W.L., Heaman, L.M., and Watters, B.R. (1999): Lithogeochemistry of volcano-plutonic assemblages of the southern Hanson Lake Block and southeastern Glennie Domain, Trans-Hudson Orogen: evidence for a single island arc complex; Can. J. Earth Sci., v36, p209-225.

Morelli, R.M. (2009): Sub-Phanerozoic geological mapping of the Precambrian Flin Flon–Glennie Complex: 2009 update; in Summary of Investigations 2009, Volume 2, Saskatchewan Geological Survey, Sask. Ministry of Energy and Resources, Misc. Rep. 2009-4.2, Paper A-11, 18p, URL <http://er.gov.sk.ca/adx/aspx/adxGet Media.aspx?DocID=11862,11861,11458,11455,11228,3385,5460,2936,Documents&MediaID=36802&Filename=A-11+Morelli.pdf>.

__________ (2010): Update on interpretive geological mapping of the sub-Phanerozoic Flin Flon and eastern Glennie domains, Saskatchewan; in Summary of Investigations 2010, Volume 2, Saskatchewan Geological Survey, Sask. Ministry of Energy and Resources, Misc. Rep. 2010-4.2, Paper A-9, 16p, URL <http://er.gov.sk. ca/adx/aspx/adxGetMedia.aspx?DocID=11869,11868,11458,11455,11228,3385,5460,2936,Documents&Medihttp://er.gov.sk.ca/adx/aspx/adxGetMedia.aspx?DocID=11869,11868,11458,11455,11228,3385,5460,2936,Documents&MediaID=36842&Filename=A-9+Morelli.pdf>.

Morelli, R.M. and MacLachlan, K. (2008): Towards a revised geological map of buried Precambrian basement of the Flin Flon and Glennie domains; in Summary of Investigations 2008, Volume 2, Sask. Ministry of Energy and Resources, Misc. Rep. 2008-4.2, CD-ROM, Paper A-5, 22p.

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Natural Resources Canada (2011a): Canadian Aeromagnetic Data Base, Geoscience Data Repository, Geological Survey of Canada, Earth Sciences Sector, Natural Resources Canada, URL <http://gdr.nrcan.gc.ca/aeromag/ index_e.php>.

__________ (2011b): Canadian Geodetic Information System, Geoscience Data Repository, Geodetic Survey Division, Earth Sciences Sector, Natural Resources Canada; URL <http://gdr.nrcan.gc.ca/gravity/index_e.php>.

Padgham, W.A. (1966): The Geology of the Wapawekka Narrows Area (North Half), Saskatchewan; Sask. Dep. Miner. Resour., Rep. 87, 113p.

__________ (1967): The Geology of the Wapawekka Lake Area (North Half), Saskatchewan; Sask. Dep. Miner. Resour., Rep. 103, 57p.

__________ (1968): The geology of the Deschambault Lake district comprising the Oskikebuk Lake area, Viney Lake area (west half), the northern part of the Ballantyne Bay area and the northeast quarter of the Limestone Lake area; Sask. Dep. Miner. Resour., Rep. 114, 92p.

Pandit, B.J., Hajnal, Z., Stauffer, M.R., Lewry, J., and Ashton, K.E. (1998): New seismic images of the crust in the central Trans-Hudson Orogen of Saskatchewan; Tectonophys., v290, p211-219.

Saskatchewan Geological Survey (2003): Geology, and Mineral and Petroleum Resources of Saskatchewan; Sask. Industry Resources, Misc. Rep. 2003-7, 173p.

Simard, R-L. and McGregor, C.R. (2009): Toward a new sub-Phanerozoic Precambrian basement map of the Flin Flon Belt, Manitoba (parts of NTS 63J, K, L); in Report of Activities 2009, Manitoba Innovation, Energy and Mines, Manitoba Geological Survey, p15-21.

Simard, R-L., McGregor, C.R., Rayner, N., and Creaser, R.A. (2010): New geological mapping, geochemical, Sm-Nd isotopic and U-Pb age data for the eastern sub-Phanerozoic Flin Flon Belt, west-central Manitoba (parts of NTS 63J3-6, 11, 12, 14, 63K1-2, 7-10); in Report of Activities 2010, Manitoba Innovation, Energy and Mines, Manitoba Geological Survey, p69-87.

Syme, E.C., Lucas, S.B., Zwanzig. H.V., Bailes, A H., Ashton, K.E., and Haidl, F.M. (1998): Geology, NATMAP Shield Margin Project Area Flin Flon Belt, Manitoba/Saskatchewan accompanying notes; Geol. Surv. Can., Map 1968A/Manit. Energy Mines, Map A-92-2/Sask. Energy Mines, Map 258A-1, 54p.

White, D.J., Thomas, A.G., Jones, A.G., Hope, J., Nemeth, B., and Hajnal, Z. (2005): Geophysical transect across a Paleoproterozoic continent-continent collision zone: the Trans-Hudson Orogen; Can. J. Earth Sci. v42, no4, p385-402.