Saskatchewan Geological Survey 1 Summary of Investigations 2010, Volume 1

Preliminary Facies Characterization of the Bitumen-bearing Lower Cretaceous Dina Member (Mannville Group) of

Northwestern Saskatchewan

Dan Kohlruss 1, Per Pedersen 2

Kohlruss, D., Pedersen, P., and Chi, G. (2010): Preliminary facies characterization of the bitumen-bearing Lower Cretaceous Dina Member (Mannville Group) of northwestern Saskatchewan; in Summary of Investigations 2010, Volume 1, Saskatchewan Geological Survey, Sask. Ministry of Energy and Resources, Misc. Rep. 2010-4.1, Paper A-2, 9p.

, and Guoxiang Chi 1

Abstract Oilsands Quest Inc.’s recent extensive exploration drilling in northwestern Saskatchewan has revealed a large bitumen resource. Estimation by the company indicates a resource ranging from 1.4 billion (B) barrels to 2.3 B barrels (222 million (M) m3 to 371 M m3) of bitumen in place.

The bitumen-bearing sandstones of northwestern Saskatchewan belong to the Dina Member of the Lower Cretaceous Mannville Group, which is the stratigraphic equivalent to portions of Alberta’s McMurray Formation. In northwestern Saskatchewan, the Dina Member sandstones were extensively eroded by glacial processes and are unconformably overlain by Pleistocene glacial tills. The Dina Member was deposited unconformably on top of the erosional surface of the underlying Devonian Elk Point Group with the thickest Dina sandstones residing within Devonian paleo-topographic lows.

Analysis of 30 cored wells from northwestern Saskatchewan has revealed eight recurring sedimentary facies in the Dina Member. The facies are indicative of deposition within an incised valley with environments ranging from high-energy, non-marine fluvial deposits to fluvio-tidal transition deposits typical of the landward limits of estuarine sedimentation.

Keywords: Cretaceous, Mannville, oil sands, bitumen, Dina, McMurray, Saskatchewan.

1. Introduction The bitumen-bearing Lower Cretaceous Mannville Group of northwestern Saskatchewan has been studied since the mid 1970s with the first stratigraphic test holes being drilled between 1974 and 1976 in an effort to expand the known oil sands resource in Alberta. Bitumen-bearing sandstones were intersected in these early test holes, yet very little was understood regarding the potential resource, and further exploration ceased. In a Saskatchewan Department of Mineral Resources’ report written in 1978, geologists also identify bitumen staining in Mannville outcrops along the Clearwater River valley (Paterson et al., 1978).

In 2004, Oilsands Quest Inc. acquired Saskatchewan oil sands permits in northwestern Saskatchewan and, in 2005, began extensive exploratory drilling. The initial test holes intersecting bitumen were subsequently described and reported by Hoffman and Kimball (2006) and Ranger (2006). Further drilling resulted in abundant bitumen intersections and consequently a large resource has since been defined. Oilsands Quest Inc. estimates a resource of 1.4 B barrels to 2.3 B barrels (222 M m3 to 371 M m3) of bitumen in place (Oilsands Quest Inc., 2010).

On Oilsands Quest Inc.’s Saskatchewan properties, bitumen is hosted within sandstones of the Lower Cretaceous Mannville Group, specifically, within the Dina Member (Figure 1). The Dina Member is equivalent to the lower portions of Alberta’s McMurray Formation. Throughout the study area, the Mannville Group has been extensively eroded by Pleistocene glacial processes and was consequently overlain by a thick succession of glacial till. The Mannville Group was deposited on the underlying Devonian carbonate unconformity surface within paleo-topographic lows, much like those observed in northeastern Alberta’s Firebag tributary valley system (Ranger, 2006).

1 Department of Geology, University of Regina, 3737 Wascana Parkway, Regina, SK S4S 0A2. 2 Department of Geoscience, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4.

Saskatchewan Geological Survey 2 Summary of Investigations 2010, Volume 1

Figure 1 - Correlation of Lower Cretaceous stratigraphy in northeastern Alberta and northwestern Saskatchewan. Note: the Dina Member is stratigraphically equivalent to portions of Alberta’s McMurray Formation.

The purpose of this paper is to document in detail the sedimentological characteristics of the Dina Member in the study area, to establish correlative equivalence with strata in Alberta, and to better understand the control of sedimentary facies on the occurrence of bitumen. This paper describes the characteristics of eight sedimentary facies recognized from initial analysis of 30 cored wells from northwestern Saskatchewan and provides preliminary interpretation of the sedimentary environments.

2. Study Area and Methods The study area is subdivided into: a regional study area located north of the Clearwater River valley along the Alberta-Saskatchewan border from Township 88 Range 19 West of the 3rd Meridian to Township 101 Range 25 West of the 3rd Meridian, which will be discussed in this paper with respect to the general geology of the area; and a detailed study area within the most intensely drilled areas in Township 94 Range 24 West of the 3rd Meridian to Township 95 Range 25 West of the 3rd Meridian that will be the primary focus of this paper, and will include detailed facies descriptions (Figure 2).

Regionally, the Athabasca oil sands of Alberta are hosted within the Lower Cretaceous Mannville Group consisting of the McMurray, Clearwater, and Grand Rapids formations while the bitumen-bearing Mannville Group in Saskatchewan is hosted within the McMurray equivalent, Dina Member. The Dina Member and McMurray Formation were deposited within paleo-topographic lows found on the sub-Mannville unconformity. Overlying the McMurray Formation and the Dina Member is the Clearwater Formation shale (Alberta) or the Cummings Member shale seal (Saskatchewan). In Saskatchewan’s oil sands region, the Dina Member is preserved within a paleo-topographic low, but the Cummings Member shale has yet to be observed due to its removal by significant erosion during Pleistocene glaciation.

The detailed study area has been extensively drilled by Oilsands Quest Inc. since 2005 and encompasses the majority of their 320 exploration drill holes and 45 development drill holes. To date, approximately 30 of 365 drill cores have been logged in detail to evaluate lithology, physical sedimentary structures, biogenic structures, and stratigraphy. Based on recurring lithology and sedimentary structures, facies and facies relationships have been recorded and depositional interpretations have been made.

3. Facies Descriptions and Depositional Interpretations Within the detailed study area, the Lower Cretaceous Dina Member has been divided into eight distinct recurring facies. These divisions are based upon the combination of lithology, physical sedimentary, and biogenic structures (Table 1).

UNCONFORMITIES

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NORTHWEST SASKATCHEWAN PERIOD

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+

+

+

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+

+

++ +

++

PRECAMBRIAN

GROUPGROUPPERIOD

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Figure 2 - Location of the study area in northwestern Saskatchewan. Note the detailed mapping area where the majority of Oilsands Quest Inc.’s drilling has been undertaken.

a) Facies 1: Massive Sandstone Facies 1 is composed of very well sorted, generally sub-rounded to sub-angular, lower to upper medium-grained quartz sandstones with no visible sedimentary structures, and is distinctive for its massive appearance. Commonly the sandstones of this facies display high levels of bitumen saturation adding to the massive appearance. The bitumen acts as the “cement” for the quartz grains that would otherwise be friable and poorly indurated (Figure 3A).

The apparent homogeneity of Facies 1 can be interpreted in multiple ways. Most likely, the abundance of oil saturation is masking subtle primary physical structures and/or biogenic structures or alternatively, the sands may have been deposited very quickly resulting in sandstones with no visible stratification. Since this facies is in close association with Facies 2, a low-flow depositional regime, and has never been observed without complete bitumen saturation, it is very likely Facies 1 is a product of low-energy flow, and the extreme bitumen saturation is masking the primary structures.

b) Facies 2: Ripple Cross-laminated Sandstone Facies 2 is comprised of bitumen-cemented, centimetre-scale ripple cross-laminated, lower to upper medium-grained quartz sandstones. These sandstones occur in close relationship with Facies 1 and Facies 6 and are within, above, or below one of these two facies. Facies 2 is relatively rare and when observed no trace fossils were present (Figure 3B).

The structures in Facies 2 indicate unidirectional flow under relatively lower energy conditions. The ripple cross-laminated bedding suggests abundant sediment supply including both bed and suspended loads. This facies would have formed on the inside meanders of low flow velocity fluvial and/or estuarine point bars.

Regina

Winnipeg

Saskatoon

SASKATCHEWAN

Lake Athabasca

ALBERTA

Edmonton

MANITOBA

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Calgary

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Fort McMurray

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asca RbahtA

N

Cle ter Riarwa ver

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km40 12 16 208

S Sask River

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Table 1 - Summary of facies within the study area.

FACIES

OCCURANCE/ CONTACT

PHYSICAL SEDIMENTARY STRUCTURES

BIOGENICSTRUCTURES

DEPOSITIONAL INTERPRETATION

Facies 1: Massive sandstone(rare facies)

Generally overlies Facies 2 or Facies 3, but not exclusively.Typically grades from Facies 2 or Facies 3. Can be observed below and above Facies 6.

Massive. Composed of medium- to fine-grained quartz and very well sorted. Rare mud clasts.

Absent Part of meandering stream deposit, up-stream of tidal influence. Very well-sorted nature and/or extreme bitumen saturation makes identification of bedding features difficult.

Facies 2: Ripple cross-laminated sandstone(rare facies)

Typically found within or below Facies 6 and 1.

Ripple cross-laminated bedding Absent Deposition under unidirectional lower flow conditions on the inside bends of fluvial and estuarine point bars.

Facies 3: Planar cross-bedded sandstone(very common facies)

Generally overlies Facies 4, if present. Normally grades into Facies 4.

Planar cross-bedded sands with metre-scale bedding thickness. Commonly has thin basal conglomerate. Common mud rip-up clasts. Generally the best reservoir with highest porosities (30%+) and bitumen saturations. Common coaly debris.

Absent to rare bioturbation (Cylindrichnus). Carbonaceous debris on drapes. Rare pyrite nodules.

High hydraulic energy. Rip-ups, “striped” appearance, and reactivation surfaces may indicate tidal influence, but deposited in fluvial meandering channels and very upper reaches of estuary.

4a: Medium- to very coarse-grained trough cross-bedded sandstone(very common facies)

Typically below Facies 3, but not exclusively. Gradational with Facies 3.

Medium to very coarse grained. Common cross-bedding, very abundant directional changes, multi-directional cross-bedding and poorly sorted. Common mud clasts and wood/coal fragments. Has good to excellent bitumen saturations and generally slightly less porosity than Facies 3.

Rare to absent. High to very high hydraulic energy . Frequent directional changes deposited in fluvial channels and portions of braided streams.

4b: Pebble-lined trough cross-bedded sandstone (common facies)

Typically below Facies 3, but not exclusively. Gradational with Facies 3.

Medium to very coarse grained with common pebble-sized quartz and chert grains. Common trough cross-bedding, very abundant directional changes, multi-directional cross-bedding, and poorly sorted. Common mud clasts and wood/coal fragments. Has good to excellent bitumen saturations and generally slightly less porosity than Facies 3 or 4a.

Rare to absent. Very high hydraulic energy. Frequent directional changes deposited in fluvial channels and braided stream.

Facies 5: Pebble conglomerate(common facies)

Commonly observed above the Devonian erosional surface, but can also be seen at the base of parasequences, below Facies 4 or Facies 3.

Very coarse- to conglomerate-size quartz grains and chert pebbles. Very poorly sorted with porosities generally the poorest of the reservoir rocks (20%+). Very common wood and mud fragments/clasts.

Absent Extremely high hydraulic energy. Represents bed-load deposits of braided streams.

Facies 6: Interbedded sandstone and bioturbated mudstone (Inclined Heterolithic Strata)(rare facies)

Above Facies 1 or 2. Sand dominated with double mud drapes. Sand is ripple cross-laminated to massive appearing. Predominantly less than 10% mud and mud rip-ups.

Rare to common monospecifec group of Cylindrichnus,Rare Thalassinoides,Teichicnus, and Skolithos.

Point bar deposits and muddy tidal channel deposits.

Facies 7: Siltstone, mudstone, and coal (rare facies)

Typically overlying Devonian erosional surface below Facies 4.

In situ root fossils capping sequences, commonly convoluted bedding at sequence base. Occasional coal/wood fragments.

Roots, rare insect burrows (Macanopsis?), lack of sedimentary bedding features suggesting bioturbation. Occasional coal.

Over-bank, marsh, and/or oxbow lake deposits. Deposition from flooding events and suspension. Aerial exposure with paleosol.

Facies 8: Laminated siltstone to very fine-grained sandstone (rare facies)

Found below or within Facies 3 or 4.

Siltstone to very fine-grained quartz sand, laminated bedding, and soft sediment features such as decimetre-scale convoluted bedding and flame structures.

Bioturbated appearance.

Floodplain, over-bank deposits, and abandoned channels.

Fac

ies

4 :

Tro

ugh

Cro

ss-b

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d S

ands

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Figure 3 - A) Massive sandstone (Facies 1) composed of lower to upper medium-sized quartz grains; the sandstone appears structureless and is extremely bitumen saturated; well 05-12-95-25W3, 189.0 m. B) Ripple cross-laminated sandstone (Facies 2); note the relatively low bitumen saturation; well 16-28-94-25W3, 191.45 m. C) Planar cross-bedded sandstone (Facies 3); well 16-28-94-25W3, 190.30 m. D) Medium- to very coarse-grained trough cross-bedded sandstone (Facies 4a); well 07-01-95-25W3, 189.5 m. E) Pebble-lined trough cross-bedded sandstone (Facies 4b); well 05-12-95-25W, 201.71 m. F) Pebble conglomerate (Facies 5); well 16-32-94-25W3, 215.45 m.

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c) Facies 3: Planar Cross-bedded Sandstone Facies 3 is commonly observed in the detailed study area and is comprised of planar cross-bedded, well to moderately sorted, sub-rounded to subangular, lower medium- to upper very coarse-grained quartz sandstones. Less than 5% of upper to lower fine-grained muscovite have also been observed scattered throughout the facies. The planar cross-beds within this facies are generally metre scale in thickness and are composed of uniform fining upward, centimetre-scale, depositional lamina that impart a “striped” appearance to the beds (M. Gingras, pers. comm., 2009). Common mud rip-up clasts and wood fragments are also observed within this facies. Visible bioturbation (Cylindrichnus) is rarely observed within this facies. Facies 3 has the highest observed bitumen saturation values (Figure 3C), however throughout the southern region (south of, and portions of Township 94) of the general study area, this facies is typically water wet. When present, bitumen acts as a “cementing” agent, but when absent the sandstones are commonly friable and poorly indurated.

Facies 3 is interpreted to be deposited under high-energy conditions. Rip-ups and planar cross-bedding are used to infer that deposition occurred as metre-scale dune forms migrating within meandering fluvial to upper estuarine channels. The extremely low density of biogenic structures (very rare Cylindrichnus) supports the theory of a meandering fluvial channel to upper estuary channel depositional environment where water conditions would be fresh to brackish (Pemberton et al., 2001; Ranger and Gingras, 2006). The observation of a “striped” appearance within the planar crossbed sets has a sediment couplet or pinstripe appearance (M. Gingras, pers. comm., 2009) that can be used to suggest semidiurnal processes and tidal influence. The coarse-grained portion would have been deposited during flood tidal waters, and the fine grained portions collected during slow tidal water periods of spring and neap tides (Ranger and Gingras, 2006).

d) Facies 4: Trough Cross-bedded Sandstone Facies 4 is comprised of variable grain size trough cross-bedded sandstone. This facies is commonly highly bitumen saturated and is an important facies with respect to the bitumen resource within the study area. Facies 4 has been subdivided into two sub-facies based primarily on grain size.

Facies 4a: Medium- to Very Coarse-grained Trough Cross-bedded Sandstone

Facies 4a is comprised of poorly sorted, subrounded to subangular, medium- to very coarse-grained trough cross-bedded quartz sandstone. Within Facies 4a crossbed sets fine upwards and are typically bitumen “cemented”. Mud rip-up clasts and wood fragments are typically present at bedform bounding surfaces. There are no visible biogenic structures observed within this facies (Figure 3D).

Facies 4a is interpreted to have formed in a high-energy depositional system within fluvial meander or braided channels where frequent directional changes occur. The bedforms were likely deposited in the lower portions of the meander or braided channel sequences along the bases of the channels, and migrated in a downstream direction. The absence of mud also points to high-energy flow conditions, where clay and mud particles would have remained in suspension.

Facies 4b: Pebble-lined Trough Cross-bedded Sandstone

Facies 4b is notably coarser than Facies 4a. Most evident is the presence of pebble-sized chert and quartz grains at the bounding surfaces of the decimetre-scale trough crossbed sets. This facies is also comprised of poorly sorted, sub-rounded to sub-angular, medium- to very coarse-grained quartz sandstone with cross-laminated bed-sets that fine upward from pebbly to medium grained. Facies 4b sandstone is commonly bitumen “cemented”, and also contains common mud rip-up clasts and common wood fragments (Figure 3E).

Facies 4b represents a very high-energy depositional system. The pebble-lined trough cross-beds within this facies exhibit frequent bounding surfaces and are considered to have been deposited within the lower portions of a rapidly shifting meander or braided fluvial sequence. The bedforms were deposited at the base of fluvial channels and migrated downstream. The absence of silt and mud also point to high-energy flow conditions, since fine sediments would have remained in suspension.

e) Facies 5: Pebble Conglomerate Facies 5 is primarily comprised of pebble-sized quartz and chert grains with minor coarse- and medium-grained quartz infilling between the pebbles, comprising the conglomerate matrix. The conglomerate is very poorly sorted with angular to sub-angular pebbles and grains. This facies is commonly bitumen “cemented”; however, it also generally has the lowest porosity (20%) of any of the Dina Member facies within the detailed study area. The limited porosity is due to the poor sorting of the sediments and, as such, this facies is considered to have low

Saskatchewan Geological Survey 7 Summary of Investigations 2010, Volume 1

reservoir potential. Facies 5 also has common wood fragments and/or mud clasts throughout. This facies is commonly observed directly overlying the Devonian unconformity surface and below Facies 4. No biogenic structures were observed in this facies (Figure 3F).

Facies 5 was formed within the highest energy depositional environment of all the facies observed, and is considered to represent the uppermost reaches of the alluvial plain within a braided stream system and/or the channel lag deposits within a point bar sequence. Facies 5 sedimentation occurs where insufficient discharge is present to carry the sediment load.

f) Facies 6: Interbedded Sandstone and Bioturbated Mudstone Facies 6 is comprised dominantly of massive to ripple-laminated quartz sandstone, interbedded with patchy to moderately bioturbated mudstone. The sandstone portions of Facies 6 are sedimentologically similar to Facies 1 and 2. This facies is considered to represent a gradational transition from either of Facies 1 or 2. Up to 10% of Facies 6 is comprised of bioturbated mudstone. The bioturbation is rarely to commonly observed, and can be seen anywhere within the mudstone, as well as at the bedding contacts with the sandstone. The trace fossils are a relatively monospecific assemblage that includes: common Cylindrichnus; rare Thalassinoides; rare Skolithos, and rare Teichicnus (Figures 4A to 4C).

Facies 6 is indicative of deposition within brackish water point bars of fluvial or estuarine meander channels, and muddy tidal channels within the upper reaches of an estuary. The low diversity and small size of the trace fossils is indicative of low and fluctuating salinities of brackish water conditions (Pemberton et al., 2001; Ranger and Gingras, 2006). The presence of massive to ripple-laminated sedimentary structures are also indicative of the upper portions of a typical point bar depositional sequence as it migrates laterally, where flow energy and grain size are decreased.

g) Facies 7: Siltstone, Mudstone, and Coal Facies 7 consists of light-coloured (very light grey to white) siltstone commonly grading into mudstone, which is often rooted (Figure 4D). Facies 7 mudstone can be carbonaceous, often grading into coal. The mudstones and siltstones can both be observed having convoluted bedding, suggesting some degree of soft sediment deformation. Besides coal beds, rare coal fragments and wood fragments are also observed. In the 13-21-95-24W3 core, a continental insect burrow was observed (Macanopsis?) (Figure 4E) (M. Ranger, pers. comm., 2010).

The light-coloured mudstones are interpreted to be the result of pedogenesis on a floodplain, while organic-rich to coaly mudstone represents marsh or oxbow lake deposits. Siltstone grading to mudstone is considered to represent over-bank deposits from flooding events and suspension sedimentation.

h) Facies 8: Laminated Siltstone to Very Fine-grained Sandstone Facies 8 is comprised of light grey unconsolidated laminated siltstone interbedded with very fine-grained sandstone. The very fine-grained sandstone is observed as flasers within the siltstone. This facies has very fine laminated bedding with common centimetre-scale soft sediment deformation features such as convoluted bedding, load casts, and flame structures. Although no specific visible biogenic structures were observed, the overall appearance does seem bioturbated. Facies 8 is observed within Facies 3 and 4. No bitumen staining is observed in this facies (Figure 4F).

Facies 8 is interpreted as siltstone deposited on a floodplain as over-bank deposits during seasonal flooding events when levees are bypassed.

4. Summary Initial core analysis of the bitumen-bearing Lower Cretaceous Mannville Group in northwestern Saskatchewan has lead to the recognition of eight recurring sedimentary facies within the Dina Member. Sedimentary structures recognized in these facies are primarily from bedforms indicative of unidirectional flow with occasional evidence of bidirectional flow. The bedforms occur as cross-beds, ranging from centimetre to metre scale. Both trough and tabular cross-stratification are observed where trough cross-bedding is interpreted to have formed in a high-energy environment with unidirectional flow, while the tabular cross-bedding represents a high, but relatively lower energy environment that formed via either unidirectional or bidirectional flow regimes.

Sedimentologically, the facies range from a pebble conglomerate, coarse- to fine-grained sandstones, siltstones and mudstones, and when the facies are compared to a typical depositional sequence, they represent an overall fining-upwards succession.

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1 cm

1 cm

1 cm

1 cm 1 cm

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Cy

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Figure 4 - A) Interbedded sandstone with bioturbated mudstone (Facies 6); trace fossils include Cylindrichnus (Cy); well 16-28-94-25W3, 191.30 m. B) Interbedded sandstone with bioturbated mudstone (Facies 6); trace fossils include Teichichnus (Te); well 05-12-95-25W3, 213.50 m. C) Interbedded sandstone with bioturbated mudstone (Facies 6); trace fossils include Thalassinoides (Th); well 16-28-94-25W3, 182.93 m. D) Rooted organic-rich siltstone and light coloured mudstone (Facies 7); pedogenic fabric with rootlets (R); well 13-21-95-24W3, 181.45 m. E) Organic-rich mudstone (Facies 7); trace fossils include continental insect burrow, Macanopsis? (Ma); well 13-21-95-24W3, 180.47 m. F) Laminated siltstone and very fine sandstone (Facies 8); well 05-34-94-25W3, 231.80 m.

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Ichnofossils were mostly absent, but were observed within three facies and were typically very small and of low diversity.

Preliminary interpretation of the sedimentary structures, sedimentology and ichnology, as well as the overall facies relationships, suggest a depositional setting that is primarily non-marine with a limited marginal-marine component. The depositional setting represents flow regimes ranging from high-energy bed-load sedimentation of braided channels to relatively lower energy point bar sedimentation of meandering channels both fully fluvial to tidally influenced. The presence of small and low diversity ichnofossil assemblages within two facies suggests variable salinity within these facies, representing a stressful living environment for typically marine organisms. This supports the inclusion of a marginal marine depositional component. This combination of observed facies therefore suggests deposition occurred primarily on an alluvial plain, including braided meander channels, and flood plain as well as portions of the most landward reaches of an estuarine system.

5. References Hoffman, G.L. and Kimball, E (2006): New cores from the McMurray Formation and underlying Elk Point Group

in northwestern Saskatchewan; in Nickel, E.H. (ed.), Saskatchewan and Northern Plains Oil & Gas Symposium Core Workshop Volume, Sask. Geol. Soc., Spec. Publ. No. 20, p17.

Paterson, D.F., Kendall, A.C., and Christopher, J.E. (1978): The Sedimentary Geology of the La Loche Area, Saskatchewan, NTS Sheet 74C; Sask. Dep. Miner. Resour., Rep. 201, 38p.

Pemberton, S.G., Spila, M., Pulham, A.J., Saunders, T., MacEachern, J.A., Robbins, D., and Sinclair, I.K. (2001): Ichnology and Sedimentology of Shallow to Marginal Marine Systems: Ben Nevis & Avalon Reservoirs, Jeanne d’Arc Basin; Geol. Assoc. Can., Short Course Notes, Vol. 15, 343p.

Ranger, M.J. (2006): The northeastern sector of the Lower Cretaceous Athabasca oil-sands basin: facies and fluids; in Gilboy, C.F. and Whittaker, S.G. (eds.), Saskatchewan and Northern Plains Oil & Gas Symposium 2006, Sask. Geol. Soc., Spec. Publ. No. 19, p249-256.

Ranger, M.J. and Gingras, M.K. (2006): Geology of the Athabasca Oil Sands – Field Guide and Overview; Field Excursion to the Outcrops and Mine Sites of the Fort McMurray Area, 5th edition, Can. Soc. Petrol. Geol., 120p.

Oilsands Quest Inc. (2010): Oilsands Quest Provides Bitumen Resource Estimate Update; URL <http://www.oilsandsquest.com/pdf/Resource_Estimate_Update_Jun10.pdf>, accessed 4 Aug 2010.