detailed study of the bingo north and bingo south gold...

Saskatchewan Geological Survey 1 Summary of Investigations 2003, Volume 2

Detailed Study of the Bingo North and Bingo South Gold Showings, Dickens Lake Area, La Ronge Volcanic Belt

Ghislain Tourigny

Tourigny, G. (2003): Detailed study of the Bingo North and Bingo South gold showings, Dickens Lake area, La Ronge Volcanic Belt; in Summary of Investigations 2003, Volume 2, Saskatchewan Geological Survey, Sask. Industry Resources, Misc. Rep. 2003-4.2, CD-ROM, Paper B-2, 12p.

Abstract The Bingo North and Bingo South showings are part of a 300 m long brittle-ductile shear zone containing resources estimated at 81,000 ounces of gold. The mineralization occurs within the eastern margin of the Bernaski Bay granitic pluton, which intrudes the southern part of the La Ronge greenstone belt. The orientation and development of metre-scale, gold-bearing shear zones were greatly influenced by northwest-trending quartz-diorite dykes with which they are intimately associated. These small-scale shear zones exhibit evidence of a complex shearing history recorded by sinistral shear-sense indicators on horizontal surfaces and moderately to steeply northwest-plunging lineations in subvertical section. The auriferous shear zones are interpreted to be antithetic sinistral transpression zones developed during dextral transpression along the northeast-trending McLennan Lake Tectonic Zone, which juxtaposed the La Ronge Domain against the sedimentary Kisseynew Domain to the east.

Keywords: La Ronge Domain, Bernaski Bay pluton, foliation, lineation, anastomosing shear zone, quartz diorite dyke, quartz veins, gold mineralization, sinistral transpression, dextral transpression.

1. Introduction The La Ronge Domain has been the focus of gold exploration since the 1940s and hosts a number of gold deposits and showings, including such past producers as the Komis, Jolu, Star Lake, Contact Lake, and Jasper mines (Figure 1; Table 1). Bingo North and Bingo South are two significant gold showings located in the southern half of this Paleoproterozoic granite-greenstone belt. They occur in a major northwest-trending brittle-ductile shear zone, the Bingo Shear Zone, developed in the northeastern part of the Bernaski Bay Pluton. Thomas (1986) suggested similarities between sheared mafic dykes, quartz veins, and associated sulphides here and at the Star Lake mine. The Bingo showings were originally discovered and drilled by Cameco Corporation and Uranerz Exploration and Mining Limited between 1990 and 1996. A preliminary resource estimate of 64,230 oz Au was based on 38 drill holes completed in 1995-96. Following additional drilling in 2002, the estimate of resources was revised to 81,380 oz Au (Gracie and Tourigny, 2002). At least ten more gold showings and prospects are known within 3 km of the Bingo North and Bingo South showings in the Benjamin Lake area.

Table 1 - Production statistics for gold mining operations in the La Ronge Belt.

Mine

Years

Tons

Grade oz Au/t

Total ounces

Komis 1996-97 129,160 0.22 26,885 Jolu 1988-91 520,525 0.342 203,571 Star Lake 1987-89 180,291 0.41 73,919 Contact Lake 1996-97 597,016 0.19 167,385 Jasper 1990-91 140,127 0.55 77,067

Previous structural studies of gold deposits in the La Ronge Domain demonstrated that the majority of gold occurrences in granitic rocks lie within major tectonic zones or along secondary faults kinematically related to the first order structures (Poulsen et al., 1987; Thomas and Harper, 1990; Roberts, 1993; Thomas, 1993). The gold-bearing structures are interpreted as oblique-slip shear zones or as major dextral transpressional structures. In order to further investigate the structural controls of gold mineralization at all scales and to improve exploration models for this type of deposit, a detailed structural study of gold showings located in the southern half of the La Ronge Volcanic Belt was undertaken in 2003. This report presents the results of detailed mapping of the Bingo North and Bingo South showings.


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2. Geological Setting The Bingo showings are located in the southern part of the La Ronge Domain, approximately 92 km north of the town of La Ronge (Figure 1).

The La Ronge Domain forms part of the Reindeer Zone (Lewry and Collerson, 1990) of the Early Proterozoic Trans-Hudson Orogen (Hoffman, 1990). This domain comprises three principal lithotectonic belts, the Central Metavolcanic Belt and two flanking metasedimentary basins, the Crew Lake Belt to the northwest, and the MacLean Lake Belt to the southwest. The Bingo showings occur within the Central Metavolcanic Belt, a northeast-trending volcano-plutonic complex with minor intercalated metasedimentary rocks (Figure 2; Thomas and Harper, 1990; Thomas, 1993). Metamorphic conditions range from greenschist to lower amphibolite, and locally, middle to upper amphibolite facies (Thomas, 1986, 1993).

The Central Metavolcanic Belt represents a volcanic arc complex consisting of an older (>1.88 Ga) succession of ultramafic and mafic volcanic rocks, overlain by a younger (1.882 to 1.876 Ga) succession of intermediate to felsic volcanic and associated volcaniclastic rocks (Maxeiner et al., 2001). These were intruded by ultramafic to felsic plutonic rocks, which can be broadly subdivided into three groups according to their composition and intrusive relationships (Thomas, 1993): 1) composite or multiphase gabbro to granite plutons emplaced between 1.875 and 1.87 Ga (Maxeiner et al., 2001); 2) relatively homogeneous granodioritic to granitic plutons dated between 1.861 and 1.855 Ga (Corrigan et al., 2001); and 3) small, homogeneous quartz-rich leucogranites to leucogranodiorites emplaced between 1.84 and 1.83 Ga (Maxeiner et al., 2001 and references therein).

The main structural features of the Central Metavolcanic Belt are ascribed to the superposition of two principal deformation events, D1 and D2. D1 deformation produced a pervasive regional northeasterly to northerly trending S1 foliation, which is axial planar to macroscopic F2 folds (Thomas, 1993). This S1 foliation dips moderately to steeply towards the west and northwest and is mostly penetrative in supracrustal rocks (Thomas, 1993). D2 deformation developed a subvertical, northeast-trending S2 foliation which is slightly discordant to D1 structures (Thomas, 1993). S2 is axial planar to northeasterly plunging F2 folds.

The La Ronge Domain is cut by several minor and major shear zones, trending easterly to northeasterly. One of the most important of these is the McLennan Lake Tectonic Zone (MLTZ), which forms the northeast-trending contact between the Central Metavolcanic Belt and the metasedimentary rocks of the MacLean Lake Belt to the east (Figure 1). The MLTZ forms a moderate to shallow, northwest-dipping complex of anastomosing shears and has been interpreted as a major D2 thrust zone which was reactivated as a dextral transpression zone (Thomas and Harper, 1990; Thomas, 1993).

Many gold-quartz veins in the La Ronge Domain are thought to have formed during the late episode of dextral transpression (see Thomas and Harper, 1990; Roberts, 1993; Thomas, 1993; Lafrance, 2002). The detailed mapping of the Bingo showings, however, shows that narrow antithetic sinistral transpressive shear zones also contain significant gold.

3. Bernaski Bay Pluton The Bingo showings are located approximately 3 km west of the McLennan Lake Tectonic Zone at the eastern margin of the Bernaski Bay Pluton (Figure 2).

The Bernaski Bay Pluton is one of a group of composite, zoned, multiphase plutons that intruded volcanics and sediments of the Central Metavolcanic Belt. It comprises granodioritic to tonalitic gneisses, mainly preserved in the northwestern part of the pluton, intruded by massive to weakly foliated, medium- to coarse-grained, biotite-bearing granite and granodiorite, which makes up the bulk of the pluton. Fine- to coarse-grained, leucocratic diorite, quartz diorite, and gabbro form a marginal phase, mainly in the eastern part of the intrusive complex (Thomas, 1986, 1993).

The pluton is transected by numerous intermediate to felsic dykes that vary in width from a few centimeters to a few metres. Northwest-trending intermediate dykes in the eastern part of the pluton acted as the loci for later shearing and emplacement of quartz veins and gold mineralization (Thomas, 1986, 1993).


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4. The Bingo Shear Zone: Bingo North and Bingo South Showings

a) Rock Types The Bingo Shear Zone, which truncates the northeastern part of the Bernaski Bay Pluton, contains the two principal gold prospects of the area (see Figures 2, 3, and 4). This major northwest-trending deformation zone has been explored for a distance of approximately 300 m along strike. The Bingo North and Bingo South showings were mapped in detail in order to characterize the lithologic and structural frameworks of the gold mineralization.

As shown in Figures 3 and 4, the mineralized shear zone truncates a complex assemblage of intrusive and volcanic rocks.

The principal rock type is a weakly deformed, inequigranular, medium-grained granodiorite made up of plagioclase (40 to 50%), quartz (10 to 15%), hornblende-actinolite (15 to 25%), and biotite (10 to 15%), with lesser amounts of epidote, chlorite, and sericite. This granodiorite is intruded by narrow, northerly trending, steeply dipping to subvertical dykes ranging in composition from gabbro through quartz diorite and diorite to aplite.

A fine-grained felsic dyke (identified as aplite in Figure 3) was observed in the southern part of the Bingo North trench. This dyke is mainly composed of quartz and is obliquely cut by the gold-bearing shear zone.

Younger, hornblende-biotite-rich dykes are commonly observed along and within the mineralized shear zones (Figures 3 and 4). They represent the principal host rocks of the gold-bearing veins. They are typically well-foliated and lineated and have a medium green to rusty color within the sulphide-rich ore zones. Hornblende, actinolite, and biotite are the main mafic minerals (10 to 40%) occurring as subhedral to anhedral poikiloblastic grains and laths displaying the strong shear zone fabric. Plagioclase (15 to 35%) occurs as anhedral crystals (1 to 3 mm) and as smaller anhedral equant groundmass. Quartz (15 to 25%) occurs mostly as recrystallized fine-grained aggregates oriented parallel to the penetrative foliation. Accessories minerals are sericite, epidote and disseminated pyrite and hematite. Minor lenses of quartz-feldspar mylonite and biotite-hornblende schist are tectonically interfingered with the quartz-diorite within the gold-bearing shear zones.

Volcanic rocks are represented by sheets and xenoliths of porphyritic trachyandesite within the granodiorite (Figure 3). A similar trachyandesitic unit was mapped in the volcanic sequence nearby (see Thomas, 1986).

b) Structural Geology

Foliation

Planar and linear structures observed in the granodiorite and dykes are ascribed to the regional deformation described by Thomas (1986, 1993). At the Bingo showing, this is represented by a weak foliation defined by the alignment of hornblende and biotite, as well as by the flattening plane of deformed xenoliths. This metamorphic foliation, termed Sm, varies from north-south to northeast-southwest and is clearly crosscut and reoriented by late shear zones (Figures 3 and 4). Sm generally dips steeply west (>65°) and contains a weakly developed, moderately northwest-plunging hornblende-biotite lineation. This S-L fabric probably corresponds to the D1 structural elements described by Thomas (1993).

Shear Zones

Detailed structural mapping of the Bingo North and Bingo South showings revealed that gold mineralization is structurally controlled and limited to the internal parts of the Bingo Shear Zone This major deformation corridor trends from northwest to north-northeast, dips steeply (>65°) towards the west, extends along strike for 300 m, and ranges from 50 cm to 5 m wide (see Figure 5). Drilling indicated that the Bingo Shear Zone has a vertical extent of at least 100 m.

In detail, the Bingo Shear Zone has a complex geometry and is made up of several smaller scale, second-order shear zones ranging from a few centimetres to 1 m wide (Figures 3, 4, and 6). They coincide with bands of intense shearing associated with a pervasive biotite-chlorite-epidote and pyrite alteration and gold-quartz vein mineralization (Figure 6). These shear zones and their related slip planes define an anastomosing network broadly similar to the continuous-discontinuous structures described by Gapais et al. (1988). The anastomosing pattern is particularly well developed at the Bingo North showing where shear surfaces surround rotated and dislocated lenses of less deformed rock (Figure 6).


Figure 3 - Structural geology of the Bingo North showing.


Figure 4 - Structural geology of the Bingo South showing.


The shear zones are developed along the contact between hornblende-biotite-rich dykes and the more competent granitic rocks of the pluton (Figures 3, 4, and 5). In general, centimetre to metre-scale shears are spatially coincident with, and overprint, the mafic hornblende-biotite dykes, along at least part of their length. Shear zone lithologies include hornblende-biotite schist derived from the quartz-diorite dykes and protomylonite and mylonite derived from altered and sheared intermediate and felsic intrusive rocks.

The anastomosing small-scale shears and the associated foliation are curviplanar surfaces oriented either parallel or at a low angle to the enveloping surface of the first-order, Bingo Shear Zone. The shear zone foliation is steeply dipping and varies in orientation from northeast to north-northeast (Figures 3 and 4).

A mineral stretching lineation defined by elongate aggregates of amphiboles and biotite is contained within the mylonitic foliation (Figures 3 and 4). This lineation plunges moderately towards the northwest (average attitude is 316°, plunge is 63° northwest). In vertical sections parallel to the mineral lineation, the foliation and slip planes are essentially subparallel and no asymmetric structures indicating the sense of shear were recognized. In contrast, on subhorizontal surfaces approximately perpendicular to the lineation, the trajectory of the foliation defines an open sigmoidal fabric that indicates a sinistral sense of shear. Locally, the foliation also shows a slight clockwise angular relationship to the slip planes and to the shear zone boundaries; this observation is also consistent with a sinistral shear sense. Combined with the steeply northwest-plunging extension lineations, these shear sense indicators show that the displacement within Bingo Shear Zone was an oblique-sinistral movement. Given the steep northwest-plunging attitude of the extension lineation, it is likely that the sense of shear in vertical section was reverse (southwest side up).

Two sets of minor brittle-ductile shears are observed in the competent granodiorite along the major shear: a northerly striking sinistral set and a northeasterly striking dextral set (Figures 4 and 5). These conjugate shears probably represent synthetic and antithetic fractures subsidiary to the Bingo Shear Zone.

Quartz Veins and Gold Mineralization

Three generations of subvertical quartz veins are distinguished at the Bingo North and Bingo South showings. V1 veins are volumetrically negligible, barren, quartz-biotite-chlorite extensional veinlets striking northeast to east at high angles to the shear foliation and to the shear zone boundaries. They are mainly well preserved along the structural footwall (east side) of the ore zone (Figure 7A). These veins are very irregular and resemble a deformed stockwork. They record considerable internal deformation, including folding and boudinage. Cross-cutting relationships suggest that V1 veins probably pre-date shear zone development and the emplacement of gold mineralization.

The second generation of veins, V2, is restricted to domains with the most highly strained and altered rocks within the Bingo Shear Zone. These milky quartz veins have subsidiary amounts of pyrite-chalcopyrite-pyrrhotite and are gold bearing. They strike northwest to north-northeast and are essentially subparallel to the shear zone foliation. V2 veins vary in thickness from a few centimetres to 60 cm and are continuous for up to 10 m. They represent mineralized segments of the anastomosing second-order shear zones. Some of the V2 veins occupy the entire width of the host fractures.

The principal mesoscopic structures observed in V2 veins are pinch-and-swell and symmetrical boudinage (Figures 3, 4, and 7B). Locally, V2 veins and the enclosing shear foliation are folded into centimetre-scale S-shaped folds

Figure 5 - Detailed view of the Bingo Shear Zone at the Bingo North showing. Note the rusty color due to intense pyritic alteration along the anastomosing gold-sulphide-bearing shears.

Figure 6 - Plane view of anastomosing auriferous shear zones, Bingo North showing.


which plunge moderately towards the northwest (see Figure 4). Some veins also exhibit rotated asymmetrical boudins. All of these mesoscopic structures result from the sinistral shear component along the mineralized shear zone.

The third type of veins, V3, are millimetre-scale, en echelon extensional quartz veins trending east-northeasterly to northeasterly. They are developed in weakly deformed intrusive rocks and are typically well exposed on the structural hanging wall of the ore zone. They are invariably barren and probably developed near the end of the oblique-slip shearing increment along the Bingo Shear Zone.

5. Folds and Brittle Faults The undulating attitude of the Bingo Shear Zone is caused by a late folding event which overprinted earlier structures (Figure 4). This post-mineralization event is mainly evident in the southern part of the Bingo North showing where an open fold has reoriented the entire zone (Figure 4). A spaced crenulation cleavage axial planar to the synform has a general north-northeast trend and dips steeply towards the east. The cleavage is penetrative within the most anisotropic tectonites and is associated with centimetre- to metre-scale transposition structures developed in the hinge zone of the major fold (Figure 8).

The transposition produced north-northeast-trending injection structures that created minor subvertical oreshoots along the ore zone.

Minor northeasterly and easterly striking, subvertical brittle faults of unknown displacement are also present. The effects of these late faults on the geometry of the Bingo Structure are negligible (Figure 4).

6. Discussion and Conclusions On the basis of our detailed structural mapping, a number of important points can be made about the

Figure 7 - Three generations of quartz veins within the Bingo Shear Zone. A) complexly deformed and brecciated V1 vein; B) asymmetric boudins in a V2 quartz vein parallel to the shear zone foliation in mylonite at Bingo North; and C) undeformed, en echelon V3 extension veins lying on the structural hanging wall of the ore zone, Bingo North showing.

Figure 8 - Transposition structure developed parallel to the crenulation cleavage within the hinge zone of an open megafold at the Bingo North showing.


lithotectonic features of the gold-bearing Bingo Shear Zone system.

a) Deformation History The crosscutting relationships among the weakly developed foliation in the Bernaski Bay Pluton, the gold-bearing shear zones, and post-mineralization structures define three principal deformation events. The earliest one produced the regional foliation and associated lineation and involved regional shortening with nearly subvertical elongation. The second event produced the brittle-ductile shear zones and the associated shear foliation, and controlled the emplacement and deformation of the gold-bearing quartz-sulphide veins and associated alteration. The shear foliation and the lineation are likely partly inherited from the regional S-L fabric. Kinematic indicators reveal that the sense of shear was oblique-sinistral with an unknown component of dip-slip. The third event is recorded by a megafold and an associated north-northeast-trending crenulation cleavage that slightly distorted and reoriented the auriferous shears.

b) Role of the Layering Anisotropy Layer anisotropy had a marked influence on auriferous shear zone development in the Bernaski Bay pluton. The northwest-trending shear zones and gold-quartz veins developed along relatively strain-softened, incompetent hornblende-biotite-rich dykes hosted in the rheologically stiff granodiorite. Compositional heterogeneity in the pluton controlled the nucleation, propagation, and orientation of the shear zones. The northwest-trending dykes were favorably oriented for slip. As a multilayered anisotropic system, the dykes might also have influenced the bulk kinematics of the shear zones (see Dubé et al., 1989).

c) Comparison with Other Gold Deposits in the La Ronge Belt The Bingo gold occurrences share many geological attributes with such past-producing mines as Jolu, Jasper, and Star Lake.

1) The mineralization is contained within quartz-sulphide veins hosted by shear zones that transect the marginal area of granitic plutons.

2) The mineralization occurs in steeply dipping brittle-ductile shear zones characterized by a steep mylonitic foliation and steeply plunging extension lineations.

3) Gold-quartz mineralization is associated with zones of biotite-chlorite-sericite-pyrite alteration. 4) The lithological association of gold-bearing shear zones and narrow dykes is also observed at the Jolu mine in

the Star Lake pluton. On the other hand, the northwesterly orientation of the Bingo showings differs markedly from the northeasterly trends of the Jolu, Star Lake, and Jasper gold-bearing shears, and with the east-trending gold occurrences along the Byers Fault (Figure 2; Thomas and Harper, 1990; Thomas, 1993). The orientation of the Bingo Structural Zone is primarily controlled by the northwest-trending dykes along which shear zones nucleated and propagated. At Star Lake, dykes trend northeasterly (Poulsen et al., 1986; Thomas and Harper, 1990), and along the Byers Fault major lithological contacts along which gold-bearing shear zones developed strike east-northeast to northeast (Lafrance, 2002).

Several other gold occurrences are also hosted by brittle-ductile shear zones in the vicinity of the Bingo North and Bingo South showings (Figures 2 and 9). The most significant include the northwest-trending Bingo East and the north-trending Pond showing. These two showings occur in the Bernaski Bay pluton and are hosted by brittle-ductile shear zones showing an apparent sinistral shear sense on subhorizontal surfaces (R. Avery, pers. comm., 2003). Towards the east, the Arseno showing is hosted by east-northeast dextral shear zones truncating the gabbroic phase of the Bernaski pluton. This dextral shear probably represents the conjugate counterpart of the north- to northwest-trending sinistral shear zones hosting the Bingo North, Bingo South and Bingo East showings.

Additional gold showings occur along the Dickens Lake Fault approximately 5 km to the north of the Bingo showings (Figures 2 and 9). All of these gold occurrences are shear-hosted and show a general easterly to east-northeasterly trend. Further detailed structural study of them should provide constraints on the geometry and kinematics of the mineralized structures.

d) Tectonic Model An important characteristic of the Bingo Shear Zone is sinistral-transcurrent shear sense indicators on horizontal surfaces and moderately to steeply plunging elongation lineations in vertical sections (i.e., perpendicular to the steep shear foliation). A comparable geometry is described for the gold deposits along the east-northeast trending Byers Fault, where mineralized shear zones have a steeply plunging lineation and dextral shear-sense indicators in plan


view (Lafrance, 2002). Similarly, the northeast-trending mineralized shear zones of the Jolu and Star Lake deposits show coexisting step lineations and evidence for dextral strike-slip on horizontal surfaces (Lafrance, 2002). Thomas and Harper (1990) and Thomas (1993) interpreted the shear zones of the Jolu-Jasper and Byers Fault areas as subsidiary structures of the regional McLennan Lake Tectonic Zone, a major east-directed thrust zone which was reactivated as a dextral transpression zone (Poulsen et al., 1987; Thomas and Harper, 1990; Thomas, 1993).

Consequently, it is probable that the Bingo Shear Zone is a zone of oblique-sinistral transpression developed between the Dickens

Lake Fault to the north and the McLennan Lake Tectonic Zone during the oblique dextral convergence of the La Ronge and the Kisseynew domains (Figure 9). In this scenario, the northwest-trending Bingo Shear Zone would be an antithetic structure developed during the bulk dextral transpressional movement. Alternatively, the mineralized structures at Bingo may have been initiated as thrust faults that were later reactivated as sinistral strike-slip faults. Although this interpretation is consistent with coexisting steep lineations and sinistral shear-sense indicators, the lack of northeast-side-up shear sense does not support an early thrust model for this shear zone. Hence, the Bingo Shear Zone is best interpreted as a zone of sinistral transpression.

e) Implications for Gold Exploration Gold exploration in the La Ronge Domain has traditionally been focused along northeast-trending structures parallel to the general tectonic grain of the belt and along the subsidiary east-northeast-trending structures in the Byers Fault area. The present study shows that northwesterly trending structures at a high angle to the northeast- and east-trending structures are potentially also important for gold mineralization. Typically, the northwesterly trending structures are spatially associated and developed along hornblende-biotite-rich dykes less competent than the host granodiorite. Recognition of this lithological association with gold-bearing shear zones has important implications for exploration. For example, it would be interesting to determine the geochemical composition of mineralized northwest-trending dykes and compare them to barren dykes of similar orientation. Mapping the dyke density may also be a useful way to detect mineralized targets.

In addition, it should be noted that gold mineralization at Bingo occurs in relatively small-scale deformation zones compared to other intrusion-related gold deposits of the La Ronge Domain. Such small-scale targets may be recognized by several key features, including: 1) their discordant relationship to the general northeast-trending foliation of the La Ronge Domain and abrupt reorientation of this inherited fabric at their margin; 2) increased amounts of associated biotite-chlorite-epidote and sulphides; 3) the transition from coarse-grained lithologies to fine-grained mylonitic rocks and schist within the gold-bearing structures, and by 4) transition from steeply plunging to shallow plunging extension lineation, a geometry which should occurred along zones of oblique convergence and transpression.

Thomas (1993) noted that many mineralized northeast-trending gold-bearing veins lack severe hydrothermal alteration in the La Ronge Domain. Bingo North and Bingo South showings, however, display a pervasive visible hydrothermal alteration (e.g., biotitization and pyritization) that can be easily recognized at an early stage of the exploration program.

7. Acknowledgments The author would like to thank Golden Band Resources Inc. for helpful collaboration and permission to publish this paper. Many thanks also go to Breanna Uzelman for assistance in the field and to Mike O’Brien and Bill Slimmon

Figure 9 - Geological sketch showing the Bingo Shear Zone as an antithetic structure related to the MLTZ and Dickens Lake Fault, which both have late dextral displacement (not to scale).


for help with the figures. Nathalie Thompson is greatly acknowledged for assistance in editing the final version of this paper.

8. References Ashton, K.E. (1999): A proposed lithotectonic domain re-classification of the southeastern Reindeer Zone in

Saskatchewan; in Summary of Investigations 1999, Volume 1, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 99-4.1, p92-100.

Corrigan, D., Maxeiner, R.O., and Harper, C.T. (2001): Preliminary U-Pb results from the La Ronge–Lynn Lake Bridge Project; in Summary of Investigations 2001, Volume 2, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 2001-4.2, p111-115.

Dubé, B., Poulsen, K.H., and Guya, J. (1989): The effects of layer anisotropy on auriferous shear zones: The Norbeau mine, Quebec; Econ. Geol., v84, p871-878.

Gapais, D., Bale, P., Choukroune, P., Cobbold, P.R., Mahjoub, Y., and Marquer, D., (1988): Bulk kinematics from shear zone patterns: Some field examples; J. Struc. Geol., v9, p635-646.

Gracie, A. and Tourigny, G. (2002): Saskatchewan Exploration and Development, Sask. Industry Resources, 18p.

Hoffman, P.F. (1990): Subdivision of the Churchill province and extent of the Trans-Hudson orogen; Geol. Assoc. Can., Spec. Pap. 37, p15-40.

Lafrance, B. (2002): Shear hosted gold occurrences in the Proterozoic La Ronge Volcanic Belt, Saskatchewan; Field A3 Guidebook, Geol. Assoc. Can./Mineral. Assoc. Can., 37p.

Lewry, J.F. and Collerson, K.D. (1990): The Trans-Hudson orogen: Extent, subdivision and problems; Geol. Assoc. Can., Spec. Pap. 37, p121-141.

Maxeiner, R.O., Corrigan, D., Harper, C., MacDougall, D., and Ansdell, K. (2001): Lithogeochemistry, economic potential, and plate tectonic evolution of the “La Ronge–Lynn Lake Bridge”, Trans-Hudson Orogen; in Summary of Investigations 2001, Volume 2, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 2001-4.2, p92-100.

Poulsen, K.H., Ames, D.E., and Galley, A.G. (1986): Gold mineralization in the Star Lake pluton, La Ronge belt, Saskatchewan: A preliminary report; in Current Research, Part A, Geol. Surv. Can., Pap. 86-1A, p205-212.

Poulsen, K.H., Ames, D.E., Galley, A.G., Derome, I., and Brommecker, R. (1987): Structural studies in the northern part of the La Ronge Domain; in Summary of Investigations 1987, Volume 2, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 87-4, p107-114.

Roberts, R.G. (1993): The relationships between gold-bearing quartz veins of the Star Lake and Island Lake plutons, and the deformation of the plutons; Sask. Energy Mines, Open File Rep. 93-5, 29p.

Thomas, D.J. (1986): Bedrock geological mapping, Esmay Lake area (part of NTS 73P-10 and -15); in Summary of Investigations 1986, Saskatchewan Geological Survey, Sask. Energy Mines, Misc. Rep. 86-1, p19-31.

__________ (1993): Geology of the Star Lake–Otter Lake Portion of the Central Metavolcanic Belt, La Ronge Domain; Sask. Energy Mines, Rep. 236, 132p.

Thomas, D., and Harper, C. (1990): Regional- and deposit-scale characteristics of the structurally-controlled lode gold mineralization in the La Ronge Gold Belt; in Beck, L.S. and Harper, C.T. (eds.), Modern Exploration Techniques, Sask. Geol. Soc., Spec. Publ. No. 10, p181-193.

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