CO2 Sequestration and Coalbed-Methane Potential of Lower (Lower ) , Southern – Preliminary Investigations

S.L. Bend 1 and M.C. Frank 1

Bend, S.L. and Frank, M.C. (2004): CO2 sequestration and coalbed-methane potential of lower Mannville Group (Lower Cretaceous) coals, southern Saskatchewan – preliminary investigations; in Summary of Investigations 2004, Volume 1, Saskatchewan Geological Survey, Sask. Industry Resources, Misc. Rep. 2004-4.1, CD-ROM, Paper A-12, 17p.

Abstract

The long-term storage of CO2 within deep non-mineable seams is widely considered to be a viable means of reducing greenhouse gas emissions. Recent studies have also shown that injection of CO2 into coal seams can enhance the production of coalbed methane (CBM), a more environmentally friendly fuel than oil. The Lower Cretaceous Mannville Group (Aptian-) of southern Saskatchewan contains coals of sub- bituminous rank occurring within the Cantuar Formation. Because of their low economic importance, these coals have received only minimal attention in the past, and little is known of their distribution and character. A major project was recently initiated to assess the CO2 sequestration and CBM potential of the Mannville coals. Analysis of geophysical well logs, core, and drill cuttings was performed along with coal petrography in order to identify areas of the thickest, most extensive coal deposits, and to determine their petrographic characteristics. This report presents some preliminary data on coals of the lower Mannville Group interval (Dina to General members).

To date, regions of thick (up to 5.5 m), laterally continuous (up to 65 km) coal in the lower Mannville Group have been identified in four principal areas: Winter-Senlac, Paleovalley, Unity- embayments, and the Empress Basin. These areas generally coincide with the position of paleovalleys and their embayments occurring along the margins of the Unity, Kindersley, and paleouplands. This paleotopography reflects erosion of the pre-Cantuar surface, on which the paleovalleys acted as sites for peat formation and accumulation in early Cantuar times. The most significant coals in these areas are those of the Cummings and members, in the lower part of the stratigraphic interval. The Cummings and Lloydminster coals generally range from 1 to 3 m thick in the principal coal areas, and are >5 m thick in the central part of the Kindersley Embayment, and the eastern part of the Kerrobert Paleovalley. The Cummings coal is generally restricted to isolated occurrences within paleovalleys. The Lloydminster coal is also best developed within paleovalleys, but may onlap paleoupland margins to a greater extent than the older Cummings coal, and provides a link across the Unity Paleoupland terrace between the Kerrobert Paleovalley and Winter-Senlac coal areas. Thick coals are also developed within the Dina (up to 3.3 m), Rex (up to 4.5 m), and General Petroleums (up to 1.5 m) members, but these occurrences are more localized than those of the Cummings and Lloydminster members.

The coals of the lower Mannville show a great deal of vertical variation in that they appear dominated by dull and shaly coal lithotypes with subordinate intervals of vitrinite-rich bright and banded coal. In general, petrographic analysis supports the lithotype analysis, except in cases where stored coal is highly oxidized and erroneously appears dull. In such cases the vitrinite content is highly underestimated.

Using data presented here, and from what is currently known elsewhere, the volume of CO2 that could potentially be sequestered in the Kindersley Embayment is estimated at 2.16 x 1016 cm3, which equates to a mass of 42.7 x 106 tonnes of CO2. Keywords: Lower Cretaceous, Aptian-Albian, Mannville Group, Cantuar Formation, Cummings Member, Lloydminster Member, Saskatchewan, Kerrobert Paleovalley, Kindersley Paleovalley, coalbed methane, CO2 sequestration, coal petrography.

1 Department of Geology, University of Regina, 3737 Wascana Parkway, Regina, SK S4S 0A2.

Saskatchewan Geological Survey 1 Summary of Investigations 2004, Volume 1 1. Introduction

Geological sequestration of carbon dioxide (CO2) may be an environmentally acceptable method of reducing atmospheric greenhouse gas emissions (U.S. Department of Energy, 1999) in compliance with the Kyoto Accord on Climate Change. Among the methods which have been proposed, sequestration in deep, non-mineable coal seams is perhaps the most attractive for several reasons (Stanton et al., 2001):

1) coal can trap CO2 for long periods of time;

2) CO2 is primarily held within coal by adsorption onto the surface of coal micro- and meso-pores, rather than merely infilling pore voids; coal is, therefore, far superior as a gas reservoir than more conventional lithologies such as ;

3) CO2 injection can enhance the production of coalbed methane (CBM); and

4) globally, major coal basins with sequestration potential occur near many CO2-emitting sources.

As well as having a large CO2-storage potential, coals have the ability to generate large quantities of gas. The thermal maturation of coal results in the evolution of various gases, which are dominated by methane (typically >95%), and may also contain lesser amounts of other gases such as ethane, CO2, N2, and O2. The thermogenic gas- generation potential of a coal seam is dependent on its thermal maturity (coal rank) and petrographic composition. Peak gas generation occurs at medium- to low-volatile bituminous rank (e.g., Taylor et al., 1998), with vitrinite-rich (bright) coals being more gas-prone than inertinite-rich (dull) coals. Coal seams typically act as both source rock and reservoir, with up to half of the methane generated remaining within the coal, chemically adsorbed to the coal surface. In addition to thermogenically sourced methane, coals may also act as a source for biogenic methane. The combined methane-production and gas-storage abilities of coal have led to the development of the CO2 Sequestration-Enhanced Coalbed-Methane (CO2-ECBM) concept.

The CO2-ECBM concept is a synergistic approach that has CO2-sequestration potential, by adsorbing CO2 onto the coal, coupled to the enhanced co-production of sorbed methane from deep, non-mineable coal seams. Non- enhanced CBM recoveries are typically around 50%, while enhanced CBM recoveries of 70% have been reported (Reeves, 2001). The conventional production of coalbed methane requires an initial dewatering phase, which opens the cleats (naturally occurring fractures) and reduces formation pressure, thereby promoting the desorption of methane. The factors controlling CBM production include porosity, permeability, formation pressure, and hydrogeological regime of the coal (Scott, 2002). Coals below depths of ~2000 m are usually not considered as having economic CBM potential, due to high burial pressures which reduce permeability.

The gas-sorption properties of coal are primarily dependent on petrographic composition, moisture content, and formation pressure. Bench-top tests have shown that CO2 is roughly twice as adsorbing on coal as methane (CH4) at an approximate ratio of 2:1 (Gasem et al., 2002; Tamon et al., 2003). Also, the density of the adsorbent CO2 is high, approaching that of a liquid. Other studies (Reeves, 2001) testing impure mixtures of CO2 and N2 (i.e., typical of flue gas) have demonstrated that CO2-adsorption is enhanced in the presence of N2, yielding approximate ratios of 4:2:1 (CO2:N2:CH4). This enhancement is due to the creation of partial-pressure disequilibria within the gaseous phase, resulting in the ‘pull’ (N2 interaction) and ‘push’ (CO2 interaction) of CH4 within cleats and micropores of the coal (Reeves, 2001).

Current projects that highlight the attraction of CO2-ECBM as a means of using coal in an environmentally acceptable manner and utilizing the adsorptive properties of coal to reduce greenhouse gas emissions include:

1) U.S. Department of Energy Carbon Sequestration Program – Cretaceous coals of the San Juan Basin in Colorado/New Mexico; 2) Research Council/International Energy Agency (IEA) Greenhouse Gas Research and Development Program – Cretaceous and Tertiary sub-economic and non-mineable coals in Alberta; 3) European Union RECOPOL Project – coals of the Upper Silesian Basin in Poland; and

4) Japanese Government CO2-ECBM Project – Tertiary coals of the Ishikari Basin, Hokkaido, Northern Japan. Coal-bearing sediments in Saskatchewan occur in the Lower Cretaceous Mannville Group, the Upper Cretaceous , and the Tertiary . In 2003, a research project to assess the CO2- sequestration and coalbed-methane potential of coals within Saskatchewan was initiated. This report is a summary of preliminary investigations concerning coals of the Dina to General Petroleums (GP) members of the Lower Cretaceous Mannville Group (Figure 1). Preliminary investigative work on the Sparky Coal (Mannville Group) is described elsewhere (Bend et al., 2003).

Saskatchewan Geological Survey 2 Summary of Investigations 2004, Volume 1 O 2. Coal Petrography

D WESTGATE

P

A

U

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O O

R VIKING L

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G The petrographic composition of O

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R O ALBIAN COLONY

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C O L WASECA C

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L N E 1993; Clarkson and Bustin, 1996; CANTUAR REX

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R O A LLOYDMINSTER

R Crosdale et al., 1998; Stanton et

C

M CUMMINGS

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S DINA al., 2001). A brief overview of APTIAN

BARREMIAN these relationships follows. E HAUTERIVIAN VALANGINIAN M BERRIASIAN Humic coal is derived from peat SUCCESS S2 (INSINGER) TITHONIAN and consists of a heterogeneous complex of organic entities called macerals, which are analogous to minerals in Figure 1 - Stratigraphic nomenclature of Lower Cretaceous and uppermost Jurassic inorganic rocks. However, unlike strata in southern Saskatchewan. Coals in the Dina, Cummings, Lloydminster, Rex, minerals, macerals are non- and General members were the subject of preliminary investigations reported on in this paper. crystalline and microporous. Coal macerals possess characteristic morphologies and/or distinct optical and technological properties, which are inherited from their respective floral (or faunal) precursors, or generated during peatification and coalification2 (Bend, 1992; Taylor et al., 1998). Coal macerals are sub-divided into three main groups.

Vitrinite Group – Macerals of the vitrinite group originate mainly from stem, root, and leaf material and are the most abundant macerals in the majority of coals. They have a much higher gas generation potential than the inertinite macerals. They also have higher gas sorption capacities than inertinites of similar rank, by virtue of higher internal surface areas dominated by microporosity (pore diameters <2 nm; International Union of Pure and Applied Chemistry, 2001).

Inertinite Group – Macerals of the inertinite group are derived predominantly from the same material as those of the vitrinite group, but have been subjected to one or more of the following processes: charring, mouldering, fungal attack, and aerial oxidation. Fungal remains are also placed within this group. Inertinite macerals have little hydrocarbon generative capacity.

Liptinite Group – Macerals of the liptinite group are derived from hydrogen-rich plant parts such as spores, pollen, cuticles, suberinized cork cells, resins, balsams, latexes, fats, waxes, and from algae and bacteria. The original morphology is often well preserved. Liptinite macerals have the greatest hydrocarbon generation capacity.

In hand specimen, coals are classified into lithotypes on the basis of their relative degree of brightness, with bright lithotypes generally characterized by higher vitrinite contents than dull lithotypes. The lithotype classification system used in this study is modified from that of Diessel (1965), and is presented in Table 1.

3. Preliminary Results

The four principal areas that have been identified as containing laterally continuous coal ≥1 m thick within the lower Mannville Group of Saskatchewan (Figure 2) are: 1) Winter-Senlac area (sensu Groeneveld and Stasiuk, 1984; Groeneveld, 1990), 2) Kerrobert Paleovalley, 3) Kindersley – Unity Embayments (Rosetown Coalfield), and 4) Empress Coal Basin (sensu Bell, 1974). The lowermost coals (Cummings and Lloydminster) occurring in these four areas are generally confined to paleovalleys and embayments situated on the margins of the Unity, Kindersley, and Swift Current paleouplands.

2 Peatification and Coalification: the combined physical and chemical processes which transform biological material into peat, and peat into coal, respectively.

Saskatchewan Geological Survey 3 Summary of Investigations 2004, Volume 1 Table 1 - Coal lithotype classification system used in this study (modified from Diessel, 1965). Lithotype Description Bright Coal Vitreous to subvitreous lustre; even to conchoidal fracture; brittle; may contain up to 10% dull coal in bands less than 10 mm thick. Banded Bright Coal Mainly bright coal containing thin (<10 mm) dull coal bands ranging in proportion between 10 and 40%; even fracture.

Banded Coal Contains bright and dull coal bands (all <10 mm thick) ranging in proportion between 40 and 60% each.

Banded Dull Coal Mainly dull coal containing thin (<10 mm) bright bands ranging in proportion between 10 and 40%; uneven fracture. Dull Coal Matt lustre and uneven fracture; may contain 10% of bright coal bands <10 mm thick.

Fibrous Coal Dull with satin sheen; friable; may contain up to 10% of other coal lithotypes <10 mm thick. Shaly Coal Contains between 30 and 60% of clay and silt either in intimate mixture with coal or in separate bands each <10 mm thick.

Coaly , Coaly Consists of alternating laminae (each <10 mm thick) of non-coal and coal, the latter not exceeding Mudstone, etc. 40% of total. Carbonaceous Shale Any sediment containing 60 to 90% finely disseminated carbonaceous matter.

Shale, Mudstone, Any sediment containing <10% carbonaceous matter. Siltstone, etc.

This paleotopography reflects erosion of the pre-Cantuar surface (Christopher, 2003), on which the paleovalleys acted as sites for peat formation and accumulation in early Cantuar times. The Cummings coal in the Winter-Senlac area has been extensively studied by Groeneveld and Stasiuk (1984) and Groeneveld (1990), and the reader is referred to these sources for further information. Preliminary results for the Kerrobert Paleovalley, Rosetown Coalfield, and Empress Basin follow. Coal occurrences in southeastern Saskatchewan are also briefly discussed. a) Maceral Analysis Maceral analysis for selected boreholes from the Rosetown Coalfield (Unity and Kindersley embayments, Figure 2) and the Kerrobert Paleovalley (west and east) was achieved via point-counting, in accordance with the methodology recommended by the International Committee for Coal Petrology (1971). For each sample, 500 individual analyses were gathered using an inter-point distance of 150 µm and an inter-line distance of 1 mm on polished epoxy grain mounts (particle size <250 µm). The analysis was conducted in plane-polarized reflected light, using a Leitz Orthoplan microscope, a Swift point-counting device (Model F), and with an overall magnification of ×500. The results are given in Figure 3. b) Kerrobert Paleovalley Stratigraphic cross-section G-G' (Figure 4) shows that the Kerrobert Paleovalley appears to be sub-divided into western and eastern portions at the base of the Sparky Member by an elevated ridge of strata. This ridge occurs in wells Dorset Buffalo Coulee 15-4-33-25W3 and PVR Buffalo Coulee N B4-5-33-24W3. Mannville sediments below the Sparky Member onlap this elevated Devonian ridge on both sides, and do not appear to pass across it. However, the apparent sub-division of the Kerrobert Paleovalley may merely reflect a projection of the Devonian strata from the paleovalley margin (or ‘wall’) in towards the paleovalley axis, rather than a complete termination. In such a case, the lower Mannville sediments might continue around this inward projection (or ‘nose’). Further work is needed to establish the geological architecture of the paleovalley.

West Kerrobert Paleovalley

Cummings Coal In the westernmost part of the West Kerrobert Paleovalley (NorcenInt Court A7-24-33-29W3), the Cummings coal consists of a 2 m thick main seam, with a thin (<0.5 m) rider seam 1.5 m above (Figure 4). To the east along the paleovalley, both seams thicken while the parting between them thins. At Erskine et al N Hoosier 7-12-32-27W3, the Cummings coal is represented by a 3 m thick zone containing 2.5 m of coal as measured in core. The Cummings coals continue eastward as far as ISH et al Prairiedale 7-36-32-26W3, at which point the well logs indicate a total

Saskatchewan Geological Survey 4 Summary of Investigations 2004, Volume 1

50 Lloydminster Prince Albert

Marsden PV 45 Assiniboia PV N. McGee PV

1 40 Unity PV A L

Kerrobert PV 35 Unity Unity C1 Emb. G Paleoupland G’ 3 2 Coleville Paleoupland 30 Corridor C1’ Kindersley PV KindersleyL Emb.’ Elbow PV Kindersley Rosetown Kindersley

J Plato PV 25 4 J’ Elbow Embayment 20 A’

Chaplin Regina Embayment 15 Chaplin PV Swift Current

Eastend PV Swift Current Paleoupland 10 N

5

Willowbunch Paleoupland

Assiniboia PV (South Branch) 50 km 30 25 20 15 10 5 30 Legend rd 25 20 3 Mer. Pre-Cantuar paleouplands above the Cummings Member Principal coal areas: 1 = Winter-Senlac Area, 2 = Kerrobert Paleovalley, 3 = Rosetown Coalfield, 4 = Empress Basin

Early Mannville (Aptian) paleodrainage pattern (main channels only) A–A’ Line of stratigraphic cross section Core control wells

Figure 2 - Map of southern Saskatchewan illustrating locations of principal coal areas and their relationship to paleovalleys, paleoembayments, and paleouplands. Winter-Senlac coal area from Groeneveld and Stasiuk (1984) and Groeneveld (1990); Empress Basin from Bell (1974); paleouplands and paleodrainage pattern modified from Christopher (2003). PV, paleovalley, and Emb., embayment. Locations of cross sections illustrated in Figures 4 to 8 are also shown.

Saskatchewan Geological Survey 5 Summary of Investigations 2004, Volume 1

Vitrinite Liptinite Inertinite Mineral matter

100%

90% n o ) i

t 80% t i n s e 70% o c r p e 60% m p

o e

c 50%

l m a u r l 40% e o c v (

a 30% M 20% 10% 0% 4-31-33-20W3 8-33-34-20W3 12-19-31-15W3 12-19-31-15W3 4-22-34-16W3 7-12-32-27W3 7-12-32-27W3 8-27-32-23W3 8-27-32-23W3 8-27-32-23W3 809.13 m 738.87 m 791.54 m 803.52 m 845.04 m 859.19 m 860.54 m 858.75 m 859.41 m 861 m Lloydminster Cummings Rex Lloydminster Cummings Cummings Cummings Cummings Cummings Cummings Mineral matter 3.4% 20.2% 47.2% 2.8% 3.0% 31.8% 1.0% 3.2% 18.4% 13.2% Inertinite 5.0% 52.4% 46.0% 40.0% 21.8% 29.8% 2.0% 4.8% 65.0% 19.4% Liptinite 9.6% 6.6% 3.8% 7.6% 7.0% 3.0% 12.0% 11.0% 3.2% 5.0% Vitrinite 82.0% 20.8% 3.0% 49.6% 68.2% 35.4% 85.0% 81.0% 13.4% 62.4%

Figure 3 - Petrographic data (maceral analyses) for selected boreholes from the Rosetown Coalfield (Unity and Kindersley embayments) and the Kerrobert Paleovalley (west and east). Each bar graph shows the relative proportion of macerals from the three maceral groups plus mineral matter (in volume percent). The accompanying table gives the well legal subdivision, the sample depth, associated stratigraphic unit, and corresponding analytical data. coal thickness of ~4 m, with only minimal partings. To the east of this well, the Cummings Member is thought to onlap Devonian strata.

Lloydminster Coal

The Lloydminster coal consists of a single seam ranging in thickness from <0.5 m to ~1 m between NorcenInt Court A7-24-33-29W3, and Erskine et al N Hoosier 7-12-32-27W3 (Figure 4). The coal is absent in the Baytex N Hoosier A3-31-32-26W3 well where it has been removed by a down-cutting channel sandstone of the Rex Member. The Lloydminster coal reappears in ISH et al Prairiedale 7-36-32-26W3 with a thickness of ~1 m, before onlapping Devonian strata at the eastern margin of the West Kerrobert Paleovalley.

Lithotype data indicate that both the Cummings and Lloydminster coals in the West Kerrobert Paleovalley show a great deal of variation throughout the seams which are characterized by plies of bright and dull coal, interleaved by thin layers of shale-rich coal and lesser amounts of sandstone. Petrographic analysis (Figure 3) indicates that bright coal is extremely high in vitrinite (85%) and contains very little mineral matter (1.0%). In contrast, dull coal is dominated by mineral matter (31.8%) and macerals from the inertinite group (29.8%).

The northern end of cross-section A-A' (Figure 5) shows the Lloydminster coal continuing northward across the terrace of the Unity Paleoupland into the Winter-Senlac area, where it splits into two seams, each 1 m thick.

East Kerrobert Paleovalley

Cummings Coal The Cummings coal reappears at the western margin of the East Kerrobert Paleovalley in the FCE Kerrobert DD 2D1-1-33-24W3 well. Here it consists of a lower seam 4.5 m thick, and two thinner seams ( ~1 m and ~0.5 m thick) lying within 3.5 m above the main seam. To the east (PVR Kerrobert 8-27-32-23W3), the Cummings coal consists of a 6.9 m thick coal zone containing a total of 6 m of coal as measured in core. To the east of this well, the Cummings Member onlaps Devonian strata of the Kindersley Paleoupland.

Lloydminster Coal The Lloydminster coal reappears in the East Kerrobert Paleovalley with a thickness of about 4 m in well FCE Kerrobert DD 2D1-1-33-24W3. In PVR Kerrobert 8-27-32-23W3, the Lloydminster coal splits into an upper (3.5 m) and lower (1 m) seam, separated by a 1 m parting; the base of the lower seam is only 3 m above the top of the underlying Cummings coal, giving a total thickness of 10.5 m of coal occurring within a vertical zone of 16 m.

Saskatchewan Geological Survey 6 Summary of Investigations 2004, Volume 1 Saskatchewan Geological Survey

A-A' C1-C1' L-L' ⊕ ⊕ ⊕

3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 W W W W 3 3 3 3 W W W W W W W W W W W W W 8 0 8 7 4 5 3 0 9 7 6 6 1 0 6 2 5 W W W W 2 2 1 1 - - - - 2 2 2 2 2 2 2 1 2 2 2 1 1 4 9 4 6 - 3 ------4 5 4 ------1 2 2 2 3 4 4 3 2 2 2 3 2 3 4 3 3 3 3 3 4 ------3 3 3 3 3 3 3 3 3 3 3 3 3 3 5 3 3 - - 2 ------5 2 1 - - - 3 3 3 3 4 - 5 1 2 2 1 6 4 - - 7 1 3 3 - 2 2 1 2 0 ------2 5 2 3 5 2 1 3 4 3 1 2 3 2 2 3 - 5 - - - - - 3 ------6 6 - 1 3 7 7 1 7 5 1 1 8 1 6 4 8 1 9 1 1 4 4 8 G 9 G' 0 · 780 · 760 · 770 · 690 · 750 · 790 · 780 · 780 · 760 Pense · 790 · 790 · 700 · 750 · 780 · 720 · 650 · 710 · 740 · 690 · 20 · 750 700

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Cummings 120 Pre-Mannville Dina

Summary 140

0 20 40 60 80 100 of Investigations 2004, Volume 1 Distance (km)

Legend · 750 = Depth in well GP = General Petroleums Member

= Coal R = Rex Member = Channel C = Cummings Member ⊕ = Link to corresponding D = Dina Member cross section

Figure 4 - West-east stratigraphic cross-section G-G' eastward from the Saskatchewan-Alberta border along the Kerrobert Paleovalley, across the Kindersley Paleouplands to the Unity and Kindersley embayments (Rosetown Coalfield); datum = top of Mannville Group. Location of the cross section is shown in Figure 2.

Saskatchewan Geological Survey

G-G' J-J' ⊕ ⊕ 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 W W W W W W W W W 3 3 3 3 3 3 W W W W W W W W W W 7 8 8 8 8 9 9 9 8 8 8 8 8 8 8 7 9 8 8 W W W W W W 2 2 2 2 2 2 2 2 2 ------2 2 2 2 2 2 2 2 2 2 7 8 8 8 8 8 8 - - 1 - - - - 3 1 0 - 2 0 - - 6 3 - 2 2 2 2 2 2 3 3 3 8 8 7 7 2 4 2 2 3 7 6 3 4 2 2 2 ------

------7 3 5 2 2 2 2 6 5 2 2 1 3 3 2 2 8-29-28W3 - 3 2 - - - 9 7 - 1 - - 2 - - - 4 6 0 3 3 2 2 3 2 1 - 6 - 3 1 3 2 - 2 4 - 1 1 9 1 6 4 1 - - 8 2 8 3 1 ------1 2 3 4 5 2 2 2 2 6 8 2 5 0 - - - 4 2 5 4 - - 1 0 5 1 A - - - 0 6 1 - - - 1 - - 7 5 1 6 1 6 1 1 9 1 4 1 1 1 9 7 2 5 1 1 1 3 1 1 1 1 A' 0 · 790 · 780 · 780 · 870 · 780 · 810 · 850 · 730 · 730 Pense · 780 · 800 · 820 · 710 · · 760 · 770 · 830 · · 850 · 860 · 750 · 750 · 780 730 · 760 · 840 · 840 860

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Summary 0 20 40 60 80 100 120 140 160 180 200 Distance (km)

of Investigations 2004, Volume 1 Legend · 750 = Depth in well GP = General Petroleums Member = Coal R = Rex Member C = Cummings Member ⊕ = Link to corresponding D = Dina Member cross section

Figure 5 - North-south stratigraphic cross-section A-A' from the Winter-Senlac area in the north, across the Kindersley Paleoupland to the Empress Basin and Eastend Paleovalley in the south; datum = top of Mannville Group. Location of the cross section is shown in Figure 2.

To the east of PVR Kerrobert 8-27-32-23W3, the Lloydminster Member onlaps Devonian strata of the Kindersley Paleoupland. Like the coals of the West Kerrobert Paleovalley, the Cummings and Lloydminster coals in the East Kerrobert Paleovalley also show a great deal of vertical variation and are characterized by plies of bright and dull coal interleaved by thin sandstone layers and shale-rich coal. The vitrinite content appears generally higher, but much core is missing, rendering quantification difficult. Bright coal is dominated by vitrinite (81%) and banded coal is also high in vitrinite (62.4%), whereas the dull coal is inertinite rich (65%) and dominated by the maceral Fusinite. Interestingly, the bright leaves from each of the two Kerrobert paleovalleys contain resin-impregnated vitrinite (Reso-collinite), material that has been associated with the early generation of hydrocarbons.

Coleville Corridor The Kerrobert Paleovalley contains a southerly extension (Townships 30 to 32, Range 23W3) which is not shown on the pre-Cantuar surface map of Christopher (2003). Initial work indicates that this narrow extension is ~20 km long, by <5 km wide (Figure 2), and this feature is herein referred to as the Coleville Corridor. The 16 m thick coal- bearing zone in the PVR Kerrobert 8-27-32-23W3 well (containing about 10.5 m of joint Lloydminster and Cummings coals) continues southward into the Coleville Corridor (cross-section C1-C1', Figure 6). The thickness of the coal-bearing zone ranges from 16 to 18 m in the Coleville Corridor, with 13 m total coal in Maximum N Eureka Unit D16-23-31-23W3 and PVR Eureka D15-13-31-23W3, and 14.5 m total coal in ISH Eureka 10-35-30-23W3. Farther south, the Cummings and Lloydminster members onlap the Success Formation on the Kindersley Paleoupland in the Mannville et al Lucky H 16-16-30-23 well.

G-G' ⊕ 3 3 3 3 3 3 3 W W W W W W W 3 3 3 3 3 3 3 2 2 2 2 2 2 - - - - - 2 - 3 - 1 1 0 0 4 3 2 3 3 3 3 3 - - - - - 3 - 2 - 3 3 5 6 0 2 7 2 1 3 1 1 - - - - - 2 - C1 0 - 6 5 0 6 C1' 8 0 1 8 1 1 1 1 · · 740 740 · 770 Pense · 760 · 780 · 770 · 760 20 Waseca ) m (

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120 0 5 10 15 20 25 30 35 40 Distance (km)

Legend · 750 = Depth in well GP = General Petroleums Member = Coal R = Rex Member = Channel C = Cummings Member ⊕ = Link to corresponding D = Dina Member cross section

Figure 6 - North-south stratigraphic cross-section C1-C1' from the Kerrobert Paleovalley along the Coleville Corridor to the south; datum = top of Mannville Group. Location of the cross section is shown in Figure 2.

Saskatchewan Geological Survey 9 Summary of Investigations 2004, Volume 1 c) Kindersley and Unity Embayments The Kindersley Paleovalley lies between the Kindersley and Swift Current paleouplands and trends east-northeast (Figure 2). Immediately north of Rosetown, the paleovalley widens into an embayment bordered by the Kindersley Paleoupland to the west, the Swift Current Paleoupland to the south, and a smaller paleoupland to the north. This embayment is herein referred to as the Kindersley Embayment. The Unity Embayment corresponds to the area centred around Township 34, Range 20W3, where the eastern margin of the Unity Paleoupland meets the northeast margin of the Kindersley Paleoupland (Figure 2).

Analysis of well logs, core, and drill cuttings reveals the presence of a large area (approximately 1200 km2) underlain by coal ≥1 m thick extending from Gulf Shop et al Druid 4-31-33-20W3, eastward to Tidewater Biggar Crown No. 2 9-20-34-14W3, and southeastward to Imperial Tidewater Rosetown 12-19-31-15W3. This area is herein referred to as the Rosetown Coalfield (Figure 2). The main seam in the Rosetown Coalfield is the Cummings coal, which occurs in all wells except Gulf Shop et al Druid 4-31-33-20W3 (Figure 4) and Imperial Tidewater Rosetown 12-19-31-15W3 (Figure 7). The average thickness of the Cummings coal in the Unity Embayment is 2 m, with a maximum of 4 m in Gulf Shop Springwater 13-21-34-17W3, spatially associated with the axis of the McGee Paleovalley. Analysis of six cores in the Kindersley Embayment shows that the Cummings coal increases in thickness from 1 m in the northern part of the embayment to a maximum of 5.5 m in the central part of the embayment in Tidewater Herschel Crown No. 2 15-11- 32-16W3.

G-G' ⊕ 3 3 3 3 3 3 W W W W 3 3 W W 4 6 6 5 6 6 W W 1 1 1 1 - - - - 1 1 6 6 - 2 0 - 3 1 1 1 3 3 8 4 3 3 ------7 5 3 3 - 9 - 2 1 0 3 3 9 - 1 2 - 2 2 1 - - - - 2 6 9 2 - 2 - - - 3 5 3 1 4 4 1 L 3 1 1 1 0 L' · 640 · 750 · · 720 · 700 760· · 750 Pense · 630 690

20 Waseca

40 ) m ( Sparky e

l GP l

i 60 v n

n Rex a M

80 f Lloydminster o

p o t

100

w Cummings Dina o

l e b 120 h t

p e Pre-Mannville D 140

Dina 160

180 0 10 20 30 40 50 60 70 80 Distance (km) Legend

· 750 = Depth in well GP = General Petroleums Member = Coal R = Rex Member

C = Cummings Member ⊕ = Link to corresponding D = Dina Member cross section

Figure 7 - North-south stratigraphic cross-section L-L', from the McGee Paleovalley (north) to the Kindersley Embayment (south); datum = top of Mannville Group. Location of the cross section is shown in Figure 2.

Saskatchewan Geological Survey 10 Summary of Investigations 2004, Volume 1 In core, the Cummings coal appears to be dominated by dull coal, with lesser amounts of shale-rich coal also present. However, petrographic analysis clearly reveals the highly oxidized and altered state of the core. The Cummings coal at 4-22-34-16W3 (845.04 m) and Lloydminster coal at 12-19-31-15W3 (803.52 m) are oxidized to such an extent that these vitrinite-rich coals appear dull in core. Severe oxidation is indicated by desiccation cracks, elevated reflectance, and rare reaction rims around particles of vitrinite. With the exception of a vitrinite-rich band within the Lloydminster coal (4-31-33-20W3, 809.13 m), the Cummings and Lloydminster coals throughout the Rosetown Coalfield are characterized by varying amounts of inertinite and vitrinite, and minor amounts of liptinite and mineral matter. The Rex coal (12-19-31-15W3) contains the highest recorded amount of mineral matter (47.2%). The Lloydminster, Rex, and GP coals all attain thicknesses of 1 m or greater in the Rosetown Coalfield, but are less extensively distributed across the coalfield than the Cummings coal. They are restricted to two separate areas (the western end of the Unity Embayment and the western margin of the Kindersley Embayment), with stratigraphically higher coals becoming increasingly areally restricted. The Lloydminster coal is 1 m thick at Gulf Shop et al Druid 4-31-33-20W3. In the western part of the Kindersley Embayment (Tidewater Goldburg Crown No. 1 13-22-33-16W3 and Tidewater Herschel Crown No. 2 15-11-32- 16W3), the coal is 2 m thick, and reaches its maximum thickness of 2.7 m in Imperial Tidewater Rosetown 12-19- 31-15W3, near the axis of the Kindersley paleovalley. The Rex coal consists of two seams, both <1 m thick, in the western Unity Embayment; it is 1 m thick at Imperial Tidewater Rosetown 12-19-31-15W3. The GP coal is confined to the western end of the coalfield in the Unity Embayment, where it is 1.5 m thick in Gulf Shop et al Druid 4-31-33-20W3, and 1 m thick in Numac Druid B16-35-34-20W3. The Lloydminster and Rex coals are dominated by dull and shaly coal lithotypes. Bright coal is restricted to the GP coal in the far west of the coalfield (Gulf Shop et al Druid 4-31-33-20W3).

The McGee Paleovalley extends northward from the Rosetown Coalfield (Figure 2). Stratigraphic cross-section L-L' (Figure 7) shows the presence of 3 m of shaly coal, apparently a localized thickening, near the base of the Dina Member in Liberal et al Palo 3-6-37-16W3, 20 km north of the Rosetown Coalfield. d) Empress Coal Basin The Empress Coal Basin (Figure 2) was described by Bell (1974). Analysis of well logs across the central part of the basin suggests the presence of a seam approximately 1 m thick at the top of the Cummings Member across most of the coalfield (Figures 5 and 8). Analysis of drill-cuttings from depth interval 3260 to 3270 feet (993.90 to 996.95 m) in the Ceja Alsask 10-27-25-29W3 well also supports the existence of a coal seam of approximately this thickness. While coal fragments in drill-cuttings from Altex West Bayhurst Unit 8-22-25-27W3 and Oliphant NWRCO Gorefield 3-27-25-28W3 do not exceed 5% of the total samples, the logs for these wells suggest the coal at the top of the Cummings Member is present in these wells; poor sampling may be the cause of the low coal content of the drill cuttings. Preliminary analysis of the Renaissance et al Blindloss 3-27-23-2W4, DS & W et al Graindale 10-13-25-2W4, and DS & W et al Graindale 11-6-25-1W4 wells indicates that the thickness of the Cummings coal increases to 2 m on the Alberta side of the basin. The Cummings coal is dominated by shaly coal with lesser amounts of banded dull coal in core from CdnOxy MHI Bayhurst W 4-5-25-26W3; no core has been located in the central part of the basin. e) Eastern Margin of the Swift Current Paleoupland In addition to the principal coal areas described above, coal has also been found in the Chaplin Paleovalley, west of Moose Jaw (Figure 2). The Parkbeg Crown No. 1 10-32-18-3W3 well contains a 10.8 m thick zone of black carbonaceous shale containing numerous coaly bands, and discrete seams of dull and shaly coal up to 1.4 m thick. This coal and carbonaceous shale interval occurs within the McCloud Member, which is stratigraphically equivalent to the Dina/Cummings interval. To date, no coals have been discovered in the Elbow Embayment (Figure 2), although wells are sparse in this area. f) East of Regina Mannville coals have also been reported from boreholes in eastern Saskatchewan between Moose Jaw and (Figure 9). These coals range in thickness from <1 m to 12 m, with the thickest coals (3 to12 m) occurring in the upper and lower Cantuar intervals (Price, 1963; Christopher, 2003) to the north of Yorkton and Melville (Figure 9 and Table 2).

Saskatchewan Geological Survey 11 Summary of Investigations 2004, Volume 1 Saskatchewan Geological Survey

A-A' ⊕ 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 W W W W W W W 3 3 3 9 W W W W W W W W W W 7 5 4 2 0 8 2 9 8 7 7 5 3 2 1 0 9 W W W 2 2 2 2 2 1 ------2 2 1 2 2 2 2 2 2 2 6 8 7 5 - - 5 - - - 5 5 - - 4 - - 4 - 4 2 2 1 2 5 5 5 2 5 5 5 2 2 5 2 4 4 2 4 2 ------2 5 2 2 2 2 2 5 2 2 2 2 4 7 - - - - 0 - - - 5 2 - 2 - 9 - 8 2 2 2 2 5 - 9 1 - 7 2 2 2 6 1 3 7 2 9 2 2 2 ------2 5 2 1 8 2 2 1 1 1 2 9 0 - 0 - 6 - 6 - - - J - - - - - 6 0 1 0 - J' 1 7 1 4 8 1 7 1 7 9 9 1 0 9 3 8 6 1 1 1 7 · 860 · 800 · 810 · 710 650· · 790 · · 790 · 780 760 · 910 · 840 · 770 · 820 · 760 · 680 · 930 · 800 · 800 · 760 · 810 20 Pense Waseca ) m ( 4 0 Sparky e l l i v n GP n a Rex

M 60 f o Lloydminster p o t

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D Dina

12 0 Pre-Mannville

Summary of Investigations 2004, Volume 1 140 0 20 40 60 80 100 120 Distance (km)

Legend · 750 = Depth in well GP = General Petroleums Member = Coal R = Rex Member C = Cummings Member

⊕ = Link to corresponding D = Dina Member cross section

Figure 8 - West-east stratigraphic cross-section J-J' from the Empress Basin eastward along the Plato Paleovalley to the Swift Current Paleoupland; datum = top of Mannville Group. Location of the cross section is shown in Figure 2.

N

Yorkton

Melville

Regina Swift Current Moose Jaw

Weyburn

Estevan

nd 3rd Mer. 2 Mer.

Legend 50 km = coal < 1 m = coal 1 to 3 m = coal > 3 m Principal coal areas

Early Mannville (Aptian) paleodrainage pattern (main channels only)

Figure 9 - Map of southeastern Saskatchewan showing the location of reported Cantuar-Success Formation coals east of the 3rd Meridian. Coal location data from Price (1963) and Christopher (2003).

4. CBM Potential of Mannville Coals

The very limited amount of data available prevents the full determination of the CBM potential of the Mannville coals. However, some initial comments can be made regarding the likelihood of success based upon what is currently known and analogies from elsewhere. The lower Mannville coals are highly variable in composition. This occurs both vertically and laterally within any given seam. Layers that are from 40 to 75 cm thick and that contain high proportions of vitrinite (80+%) are interspersed with layers of dull coal dominated by inertinite, shale and sandstone. While high inertinite and mineral matter contents normally tend to reduce the overall potential for both CBM generation and CO2 sequestration in coal, inertinite-rich coals are nevertheless capable of significant CBM production (Lamberson and Bustin, 1993) and gas sorption (Laxminarayana and Crosdale, 1999). Furthermore, with

Saskatchewan Geological Survey 13 Summary of Investigations 2004, Volume 1 Table 2 - Stratigraphic distribution of Cantuar-Success Formation coals reported in boreholes east of the 3rd Meridian. Data from Price (1963) and Christopher ( 2003).

No. of Stratigraphic Interval Thickness (m) Seams Well Name Well Location 12.4 1 B.A. Husky Phillips Plainview No.1 2-4-25-7W2 3.0 1 Sohio Gibbs No. 1 16-29-22-21W2 1.0 3 Tidewater Headlands Crown 4-34 4-34-24-14W2 Upper Cantuar <1 1 Tidewater Beaver Hills Crown No. 1-5 1-5-26-9W2 <1 1 Tidewater Cupar Crown No. 4-28 4-28-24-16W2 <1 1 B.A. Husky Phillips Birmingham No. 1 7-29-23-7W2 <1 2 Shell Dahinda No. 1 6-2-9-23W2 <1 1 Imperial Penzance Crown No. 1 3-30-24-25W2 <1 1 B.A. Husky Phillips Hyde No. 1 12-28-19-7W2 Middle Cantuar <1 1 Central Del Rio Elswick No. 11-18 11-18-5-12W2 <1 1 Shell Old Wives No. A16-11 16-11-14-30W2 <1 1 Sohio Western Petroleum Sheho No. 1 4-10-30-8W2 <1 1 Socony Sohio North Ormiston No. 13-13 13-13-10-26W2 2.4 1 Tidewater Headlands Crown 4-34 4-34-24-14W2 2.1 to 2.4 4 B.A. Husky Phillips Springside No. 1 8-29-27-7W2 2.1 to 2.4 2 Socony Sohio East Bethune 11-29 11-29-20-23W2 1.83 1 Tidewater Crown No. 2 4-32-25-11W2 Lower Cantuar 1.5 1 B.A. Husky Phillips Plainview No.1 2-4-25-7W2 1.0 2 Tidewater Ituna Crown No. 2 4-32-25-11W2 <1 1 B.A. Husky Phillips Birmingham No. 1 7-29-23-7W2 <1 1 Socony Sohio Mossbank No. 1 13-27-11-28W2 <1 1 Tidewater Cupar Crown No. 4-28 4-28-24-16W2 Lower Cantuar-Success 3.0 to 6.0 4 Sohio Western Petroleum Insinger No. 1 9-16-29-7W2 Success 1.52 1 Alwinsal Lanigan 3-28 3-28-33-23W2

regard to the study area, severe oxidation has altered much of the coal since it was cored, making detailed analysis difficult and chemical analysis useless.

While the low rank of the Mannville coals in Saskatchewan suggests a reduced methane generative capacity, the coals are within the early stage of gas generation, and may currently be generating gas. Producing gas pools are present within the study area, and at least some of their gas may have been generated from the coal seams; analysis of the gas isotopic data should determine if this is so (e.g., Patience, 2003). Hydrodynamic flushing and trapping of any produced gas, coupled with in situ microbial generation of methane, would enhance the overall CBM potential as is the case in the Powder River Basin, the third largest CBM-producing basin in North America, where gas production in 2001 amounted to 6.9 × 109 m3 (Ayers, 2002).

5. Estimates of CO2 Sequestration Potential

The actual amount of CO2 that can be sequestered within a coal seam is (in part) a function of its CO2-adsorption capacity and its permeability. Although none of these data currently exists for the Mannville coals, the potential volume of CO2 that could theoretically be stored can be estimated. For example, the main part of the Rosetown Coalfield in the Kindersley Embayment (Figure 2) covers an area of approximately nine townships (830 km2). A 1 m thick coal seam underlying this area would have a volume of 830 × 106 m3. For an average coal density of 1.3 g/cm3 (e.g., Taylor et al., 1998), this equates to a mass of 1.08 × 109 tonnes of coal. Published measured values of CO2-adsorption capacities for low-rank coals are very rare. The limited available data (Stanton et al., 2001; 3 Tamon et al., 2003) indicate CO2-adsorption capacities of around 20 to 25 cm /g at depths comparable to that of the Cummings coal in the Kindersley Embayment (mean depth of 815 m). Adopting a conservative value for CO2- 3 adsorption capacity of 20 cm /g, the volume of CO2 that could potentially be stored in this mass of coal would be 16 3 -3 3 2.16 × 10 cm . Given the density of CO2 (1.977 × 10 g/cm at 298°K), this relatively small area can potentially 6 3 sequester 42.7 × 10 tonnes of CO2. Using a CO2-adsorption capacity of 25 cm /g yields a potential to sequester 6 53.4 × 10 tonnes CO2.

Saskatchewan Geological Survey 14 Summary of Investigations 2004, Volume 1 6 This large amount of CO2 (42.7 × 10 tonnes) is greater than Saskatchewan’s current total annual CO2 emissions (37 6 3 6 × 10 tonnes in 2001 ) , and is about equal to 7.5% of the total annual CO2 emissions for (566 × 10 tonnes 6 in 2001). It is also more than twice the anticipated 20 × 10 tonnes of CO2 storage capacity of Encana’s Pool (Petroleum Technology Research Centre, 2000). The current estimated total volume of coal occurring in the Cummings and Lloydminster members in Saskatchewan 9 3 6 is approximately 8 × 10 m , which could potentially sequester 400 × 10 tonnes of CO2, enough to store the entire CO2 released at 2001 emission rates in the province over the next decade. If the CO2-adsorption capacity is 3 6 25 cm /g, the sequestration potential increases to 500 × 10 tonnes of CO2. With the province’s pressing need to reduce CO2 emissions, the viability of sequestering CO2 in Saskatchewan’s deep coal should be more fully assessed.

6. Proximity to Major Urban Areas

The economic factors associated with CO2-ECBM of the Mannville coals include the proximity of suitable storage sites to sources of anthropogenic CO2. Table 3 presents the distances from the main coal areas to selected urban centres within Saskatchewan. The Chaplin Paleovalley and Embayment are also included in Table 3, as coal up to 3 m in thickness is known to occur in these areas (Price, 1963; Christopher, 2003). Almost all of the major urban areas of western and central Saskatchewan are situated within 75 km of one of the principal coal areas, or areas from which coal >1 m thick has been reported. Shorter distances minimize the costs involved with the construction of CO2 distribution pipelines, such as the 328 km long CO2 delivery pipeline that was constructed for Encana’s Weyburn CO2-flood Project at a cost of approximately US$100M.

7. Summary

Initial work has identified areas of thick (up to 5.5 m), laterally continuous (up to 65 km) coal developed within the lower Mannville Group of southern Saskatchewan. The thickest, most extensive coals (Cummings and Lloydminster members) generally range from 1 to 3 m thick in the principal coal areas, and are >5 m thick in the central part of the Kindersley Embayment and the eastern part of the Kerrobert Paleovalley. The Cummings coal is generally restricted to isolated occurrences within paleovalleys. The Lloydminster coal is also best developed within paleovalleys, but may onlap paleoupland margins to a greater extent than the older Cummings coal, and provides a link across the Unity Paleoupland terrace between the Kerrobert Paleovalley and Winter-Senlac coal areas. Thick coals are also developed within the Dina (up to 3.3 m), Rex (up to 4.5 m), and GP (up to 1.5 m) members, but these occurrences are more localized than those of the Cummings and Lloydminster members. In addition to the four principal areas of coal development, coal >1 m thick has also been identified to the west of Moose Jaw (Chaplin Paleovalley), and is reported to occur in the Yorkton area.

Table 3 - Approximate distances (in kilometres) from the principal coal areas, including the Chaplin Paleovalley and Embayment, to selected urban centres in central and western Saskatchewan. The shortest distance from each centre is highlighted.

Kerrobert Rosetown Chaplin Chaplin City Population* Winter-Senlac Palaeovalley Coalfield Empress Basin Palaeovalley† Embayment†

Saskatoon 196,811 170 155 75 200 170 190 Regina 178,225 390 340 270 345 130 45 Prince Albert 34,291 225 265 195 330 290 275 Moose Jaw 32,131 320 270 205 250 55 45 Lloydminster 20,988 55 150 155 210 360 445 17,512 70 110 85 180 260 320 Swift Current 14,821 230 170 140 135 60 210 Kindersley 4,548 80 20 70 35 190 310 Notes: * From the 2001 Census of Canada, Statistics Canada. † Distances are to boreholes with coal >1 m thick.

3 Environment Canada, Greenhouse Gas Sources and Sinks On-line Database at http://www.ec.gc.ca/pdb/ghg/online_data_e.cfm.

Saskatchewan Geological Survey 15 Summary of Investigations 2004, Volume 1 Preliminary estimates suggest that the lower Mannville coals have the potential to sequester large quantities of CO2, and could make a significant contribution to the reduction of greenhouse gas emissions in Saskatchewan. While the low rank (sub-bituminous) of the Mannville coals suggests reduced thermogenic methane potential, the coals are in the early stage of gas generation and may have sourced a portion of the gas in currently producing gas pools in the area. They may also contain substantial volumes of biogenic gas. Almost all of the major urban centres of central and western Saskatchewan are situated within 75 km of areas with Mannville coal >1 m in thickness, thus potentially reducing the costs associated with CO2 and CBM transportation.

8. Current and On-going Work

Current work continues to refine the limits of known coal areas, as well as to search for new coal in other areas, particularly the Elbow Embayment, the Chaplin Paleovalley and Embayment, and the South Assiniboia Paleovalley. Petrographic analysis of coals also continues. However, actual gas contents and CO2 sorption capacities for the Mannville coals can only be determined from fresh core samples, and it is hoped that a systematic program of drilling and coring can be developed in areas identified as containing suitable coal. Further necessary work includes determination of coal permeabilities and hydrogeological regimes.

9. Acknowledgments

This study would not have be possible without the continuous co-operation and support of Saskatchewan Industry and Resources Subsurface Geological Laboratory and funding from the Petroleum Technology Research Centre (Innovation Fund). We are particularly indebted to Chris Gilboy and Melinda Yurkowski (Saskatchewan Industry and Resources), and Mike Monea (Petroleum Technology Research Centre) for their continuing support of our on- going studies. We are also grateful for critical reviews by Ian Coulson, Mike Monea, and Malcolm Wilson.

10. References

Ayers, W.B. (2002): Coalbed gas systems, resources, and production and a review of contrasting cases from the San Juan and Powder River basins; Amer. Assoc. Petrol. Geol. Bull., v86, p1853-1890.

Bell, J.A. (1974): Preliminary investigations of the Empress Coal Basin; unpubl. rep., DS&W Oil Company, 22p.

Bend, S.L. (1992): The origin, formation and petrographic composition of coal; Fuel, v71, p851-870.

Bend, S.L., Frank, M.C., Yurkowski, M., and Thain, S. (2003): Coalbed methane and CO2 sequestration potential of the Sparky Coal (Mannville Group, Lower Cretaceous), west-central Saskatchewan; in Proceedings of the 11th Williston Basin Horizontal Well and Petroleum Conference, 27-30 April 2003, Regina, 4p.

Christopher, J.E. (2003): Jura-Cretaceous Success Formation and Lower Cretaceous Mannville Group of Saskatchewan; Sask. Industry Resources, Rep. 223, CD-ROM.

Clarkson, C.R. and Bustin, R.M. (1996): Variation in micropore capacity and size distribution with composition in bituminous coals of the Western Canadian Sedimentary Basin; Fuel, v75, p1483-1498. Crosdale, P.J., Beamish, B.B., and Valix, M. (1998): Coalbed methane sorption related to coal composition; Internat. J. Coal Geol., v35, p147-158. Diessel, C.F.K. (1965): Correlation of macro- and micropetrography of some New South Wales coals; Proceedings of the 8th Commonwealth Mining and Metallurgical Congress, Melbourne, Australia, v6, p669-677. Gasem, K.A.M., Robinson, R.L., and Reeves, S.R. (2002): Adsorption of Pure Methane, Nitrogen, and Carbon Dioxide and Their Mixtures on San Juan Basin Coal; U.S. Dep. Energy Topical Rep., Contract No. DE-FC26- 00NT40924, 83p. Groeneveld, N.A. (1990): Geology of the lower Mannville strata Winter-Senlac area, western Saskatchewan; unpubl. M.Sc. thesis, Univ. Regina, 122p.

Saskatchewan Geological Survey 16 Summary of Investigations 2004, Volume 1 Groeneveld, N.A. and Stasiuk, L.D. (1984): Depositional environment of the Cummings coal and associated sediments, Winter-Senlac area, western Saskatchewan; in Lorsong, J.A. and Wilson, M.A. (eds.), Oil and Gas in Saskatchewan, Sask. Geol. Soc., Spec. Publ. No. 7, p135-147. International Committee for Coal Petrology (1971): International Handbook of Coal Petrology, Supplement to the 2nd Edition; Centre National de la Recherche Scientifique, Paris. International Union of Pure and Applied Chemistry (2001): Manual of Symbols and Terminology for Physicochemical Quantities and Units, Appendix II: Definitions, Terminology and Symbols in Colloid and Surface Chemistry, Part I, adopted 1971, 78p, Internet version, 2001, http://www.iupac.org/reports/2001/ colloid_2001/manual_of_s_and_t/. Lamberson, M.N. and Bustin, R.M. (1993): Coalbed methane characteristics of Gates Formation coals, northeastern British Columbia: Effect of maceral composition; Amer. Assoc. Petrol. Geol. Bull., v77, p2062-2076. Laxminarayana, C. and Crosdale, P.J. (1999): Role of coal type and rank on methane sorption characteristics of Bowen Basin, Australia coals; Internat. J. Coal Geol., v40, p309-325. Patience, R.L. (2003): Where did all the gas go?; Org. Geochem., v34, p375-387. Price, L.L. (1963): Lower Cretaceous Rocks of Southeastern Saskatchewan; Dep. Mines Tech. Surv., Geol. Surv. Can., Pap. 62-29, 44p.

Petroleum Technology Research Centre (2000): Request for funding for the Weyburn CO2 Monitoring Project, 84p; http://www.ptrc.ca/documents/weyburn.pdf.

Reeves, S.R. (2001): Geological sequestration of CO2 in deep, unmineable coalbeds: An integrated research and commercial-scale field demonstration project; Soc. Petrol. Eng. Annual Technical Conference, New Orleans, Pap. SPE 71749, 11p.

Scott, A.R. (2002): Hydrogeologic factors affecting gas content distribution in coal beds; Internat. J. Coal Geol., v50, p363-387.

Stanton, R., Flores, R., Warwick, P.D., Gluskoter, H., and Stricker, G.D. (2001): Coal bed sequestration of carbon dioxide; in Proceedings of the First National Conference on Carbon Sequestration, U.S. Dep. Energy and Nat. Energy Tech. Lab., May 2001, Washington, DC, 12p.

Tamon, H., Ogawa, Y., and Mukai, S.R. (2003): Adsorption characteristics of carbon dioxide and methane on coal; Coal and Safety, Japan Coal Energy Centre, v23, p44-49.

Taylor, G.H., Teichmüller, M., Davis, A., Diessel, C.F.K., Littke, R., and Robert, P. (1998): Organic Petrology; Gebrüder Borntraeger, Berlin, 704p.

U.S. Department of Energy (1999): Carbon Sequestration – Research and Development; Office of Energy, U.S. Dep. Energy, Washington, DC, 286p.

Saskatchewan Geological Survey 17 Summary of Investigations 2004, Volume 1