Petroleum Exploration Potential Of The Nechako Basin, British Columbia
NEBC Conventional Play Atlas
Exploration Assessment Of Deep Devonian Gas Plays, Northeastern British Columbia
Geological Review Of Cretaceous Reservoirs, B.C. Deep Basin, Applied To Gas Production Commingling Strategies
Geological Review Of Cretaceous Reservoirs, Ojay To Commotion Creek Area, N.E.B.C. Foothills, Applied To Gas Production Commingling Strategies
Petroleum Resource Assessment Of Whitehorse Trough, Yukon
Scoping Study Of Unconventional Oil And Gas Potential, Yukon
Conventional Reservoir Petrophysical Assessment Of 34 Eagle Plain Wells, Yukon
Northwest Territories Unconventional Natural Gas Scoping Study
Regional Characterization Of Shale Gas And Shale Oil Potential, Northwest Territories
Deep Subsurface Saline Aquifer Characterization, Central Mackenzie Valley, Northwest Territories
Deep Subsurface Saline Aquifer Characterization, Deh Cho Area, Northwest Territories
Horn River Basin Aquifer Characterization Project, Geology Report
Deep Subsurface Aquifer Characterization In Support Of Montney Tight Gas Development - Geological Report
The intermontane basins of British Columbia and the Yukon represent some of the best unconventional petroleum prospectivity in Canada today. This study summarizes the petroleum prospectivity of the Nechako Basin of south-central British Columbia. Information gained from exploratory wells, limited seismic and gravity work, and extensive surface mapping is sufficient to suggest that very large gas and oil resources may be found within the Nechako Basin.Return to Contents
The Play Atlas was developed to provide a framework for the assessment process and will provide a reference point for future analyses. The Play Atlas contains both established and conceptual plays and also contains some plays that could arguably be identified as unconventional. A broad definition of "conventional gas resources" was used and play definitions generally include the spectrum of resources that have been traditionally exploited in BC's portion of the Western Canadian Sedimentary Basin (WCSB), and are considered proven and developable with today's  technology. Unconventional Resources were deemed to be those resources that are generally not economic nor productive by today's technology or those that exist as unproven geological concepts. Examples include coalbed gas (CBG),some tight gas, shale gas and gas hydrates. Although unconventional CBG and shale gas resources are now contributing significantly to U.S. production stream they are for the most part currently unproven in NEBC.
Link to study on the BC Ministry of Energy, Mines and Natural Gas website.Return to Contents
This study reviews the Lower to Middle Devonian stratigraphic framework of northeastern B.C., and illustrates key units with a grid of regional cross-sections and gross isopach and porosity maps. This information is used to interpret depositional environments and to reconstruct regional paleogeography for each of the four major producing units.
We have identified regional networks of southwest-northeast and northwest-southeast faults, in addition to the Bovie Lake Fault Zone in the northwest and the Hay River Fault Zone in the southeast.
The most exciting potential occurs in the deep Plains and outer Foothills to the west, where westerly platform edges and potential reefal buildups offer deep, highly-pressured, unexploited reservoir trends. Platform embayments in the Slave Point and Keg River are also highly prospective, with the 2000 Ladyfern discovery being an excellent example of the potential rewards.
Geological Survey of Canada and Canadian Gas Potential Committee assessments of remaining gas potential in the Devonian of northeastern B.C. range from 6.7 to 10.2 TCF. We project that even more gas potential exists, and will be realized with the drilling of new exploratory trends.
Link to study on the BC Ministry of Energy, Mines and Natural Gas website.Return to Contents
In this review, the geological setting of each productive or potentially productive stratigraphic unit is summarized, using existing literature and internal PRCL reports. Results are presented as situation maps in which production, tests, and key geological trends and controls are illustrated.
Reservoir units are reviewed in stratigraphic order (oldest to youngest). For each unit, a situation map summarizes regional geology and production, while reservoir geology is illustrated by a type well log, type core log, and (in some cases) a stratigraphic cross-section.Return to Contents
In this review, we summarize the geological setting of each productive or potentially productive stratigraphic unit, using existing literature and internal PRCL reports. Reservoir units are reviewed in stratigraphic order (oldest to youngest). Results are presented as situation maps, in which production, tests, and key geological trends and controls are illustrated. Reservoir geology is illustrated by a type well log and graphic core logs; some of these are repeated from PRCL's 2005 study "Geological Review of Cretaceous Reservoirs, B.C. Deep Basin, Applied to Gas Production Commingling Strategies", while others specific to the Foothills have been added.
Fracturing of reservoirs arising from structural deformation is a key component of reservoir quality in the Foothills. We review briefly the genesis and importance of fracturing in Cretaceous reservoirs, with reference to structural / fractured reservoir trends currently producing in the N.E.B.C. Foothills.
Our final discussion of current multizone production / commingling practices, and geological / reservoir factors to be considered in future commingling, builds upon both stratigraphic and structural / fractured reservoir controls.Return to Contents
Whitehorse Trough is a frontier intermontane basin that is prospective for oil and gas from both conventional and unconventional reservoirs. It straddles the Yukon-British Columbia border; the Yukon portion is a triangular-shaped area covering approximately 3.72 million hectares. It features a complexly-deformed sedimentary rock section more than 7000 metres thick, with interbedded and capping volcanic rocks. Since publication of the most recent assessment, by National Energy Board (2001), significant advances have taken place in our understanding of Whitehorse Trough, and of petroleum prospectivity of northern Canada in general.
Hydrocarbon prospectivity in Whitehorse Trough is assigned to nine plays and all nine plays are prospective for gas, and three have oil potential as well. Five plays are conceptual, as sufficient information exists to support estimates of play parameters and potential. The other four are speculative, as we do not have sufficient information to support numerical estimates.
The evidence for presence of both conventional and unconventional hydrocarbons in Whitehorse Trough is compelling, and assessed volumes are sufficiently substantial to support additional exploration and assessment work.Return to Contents
This report represents the first systematic attempt to characterize unconventional hydrocarbon resources in Yukon. A review of the essential elements of unconventional accumulations, and a survey of activity in North America and worldwide set the stage for understanding prospectivity of Yukon reservoirs. Eight prospective basins are investigated, using stratigraphic, geochemical, and conventional play assessment information generated to guide conventional exploration. Because their geological histories are so varied, the basins offer a wide range of prospectivity for coals, tight reservoirs, and shales. Further work, primarily drilling and focused sampling and testing, is recommended for plays with the highest potential.
Considering current gas market conditions and distance from facilities and markets, Yukon is truly a frontier jurisdiction. However, a number of plays offer liquids potential, which is critical to economic success. As well, opportunities exist to acquire large land positions in highly prospective plays - opportunities that are becoming very scarce in more developed basins of North America.Return to Contents
In late 2010, Petrel Robertson Consulting Ltd. was contracted by Natural Resources Canada to undertake a quantitative petrophysical assessment of the petroleum exploration wells drilled in the Eagle Plain Basin of the Yukon Territory. The purpose of the assessment was to highlight prospective conventional hydrocarbon accumulations, and generate input for use in future resource assessments.
The data necessary to undertake the assessment were provided by Natural Resources Canada, the Yukon Geological Survey and public data repositories. Thirty-one of the 34 wells drilled in the Eagle Plain Basin were deemed to have sufficient data to perform a meaningful analysis, and were subsequently interpreted with a consistent methodology and set of input parameters. Average values of shale volume, porosity, permeability and saturation were generated.
Based on three sets of cutoff criteria, determined in consultation with staff of the Yukon Geological Survey, reservoir and pay intervals were identified. The results support concluding that hydrocarbons were intersected in 19 discrete stratigraphic intervals, in 29 of the 34 wells drilled.Return to Contents
This report represents the first systematic attempt to characterize unconventional gas resources of the NWT. Although the area is lightly explored, an abundance of stratigraphic, geochemical, and conventional play assessment data, combined with analogue information from producing and prospective unconventional gas reservoirs elsewhere, have enabled the identification of prospective unconventional resources. Three categories of unconventional gas are addressed: coalbed methane (CBM), tight (low-permeability) gas, and shale gas. Gas hydrates were not addressed in this study. As well, the potential for unconventional gas in the Mackenzie Delta was not considered, as unconventional gas development techniques, particularly dense well spacing, are not considered feasible in this remote and expensive area.
This report comprises the assessment, and addresses the following:
- A general overview of unconventional gas resources and their definitions;
- A discussion of applicable analogues, and a listing of key references from the literature for unconventional gas resources in other jurisdictions;
- An overview of NWT petroleum geology as it relates to unconventional natural gas resources, including: shale gas, tight gas, and coalbed methane. Methane gas hydrates are not addressed in this study. The characteristics of each unconventional gas resource type are discussed, and the potential for their occurrence within the NWT Phanerozoic succession is evaluated. Unconventional gas potential of the Mackenzie Delta was not considered, as unconventional gas development invariably requires dense well spacing, which is not feasible in this very remote and expensive environment;
- Recommendations for future geoscientific research related to NWT unconventional gas resources; and
- Additional relevant data and recommendations.
This report assembles available outcrop and subsurface data to systematically assess, at a very regional level, shale gas and oil potential in the NWT. Analytical work and production information from equivalent shales in other areas, particularly in adjacent NEBC, provide valuable insights in support of this analysis. Two study areas, based on stratigraphy and well control density, were defined: the southern Liard - Great Slave Study Area, and the northern Peel - Mackenzie Study Area. In Liard - Great Slave, good shale gas and oil potential is seen in the Devonian Muskwa-Horn River, Devonian/Mississippian Exshaw Formation, and Cretaceous Fort St. John Group. Other thick shales, such as the Fort Simpson, Kotcho, and Banff, do not contain sufficient organic material to present attractive targets. In Peel - Mackenzie, the Devonian Horn River Group and parts of the Cretaceous Slater River Formation are prospective for shale gas and oil, while the Imperial and Arctic Red shales are organic-lean, and thus less prospective.Return to Contents
This study was undertaken to identify the deep saline subsurface aquifer potential which exists in seven subsurface units in Central Mackenzie Valley; from Lower Devonian Arnica carbonates to conglomerates of the Upper Cretaceous Summit Creek Formation. Specific objectives were: (1) Identify and characterize deep subsurface aquifers capable of supplying the large water volumes required for fracture stimulations supporting shale oil and gas development; and (2) Identify formations which have the capacity to safely accept contaminated drilling and completion fluids.
Mapping and aquifer characterization were based upon regional mapping from various Geological Survey of Canada reports, and specifically upon recent reports by Hogue and Gal (2008) and Hayes (2011). The following specific tasks were completed:
(1) Subsurface stratigraphic units with aquifer potential were identified using existing stratigraphic knowledge. Stratigraphic cross-sections were created for each aquifer to facilitate and illustrate correlations. (2) Potential aquifers were mapped in the subsurface using data from oil and gas wells, including well logs, cores (including quantitative core analysis data), sample cuttings, and well tests. (3) Maps to characterize the aquifers were created, including: gross thickness, net porous reservoir thickness, and reservoir capacity (porosity*thickness). Information from outcrop was also used to constrain mapping. (4) In order to ensure accurate and consistent aquifer characterization, all test and water analysis data were rigorously assigned to specific units within the stratigraphy mapped in this project,. Each well test was reviewed to determine reservoir pressure, fluid content, and permeability. Water analysis data were summarized to characterize water quality and chemistry. And (5) all data were compiled and interpreted to assess the potential for each stratigraphic interval to supply and accept drilling and completion fluids.Return to Contents
The study has been undertaken to identify deep saline subsurface aquifers in the Deh Cho territory capable of supplying the large water volumes required for fracture stimulations, and to identify formations which have the capacity to safely accept contaminated drilling and completion fluids.
Subsurface aquifers were defined based upon existing regional mapping, and were characterized using lithological information and borehole log data from petroleum exploration wells. Drillstem test data were used to characterize formation fluids and reservoir quality. Ten aquifer intervals exhibiting substantial reservoir quality, regional extent and lateral continuity were mapped, and local aquifer potential in several other stratigraphic intervals was noted.Return to Contents
Stratigraphic mapping and reservoir characterization were supported by interpretation of well logs, cores, sample cuttings, and well test data. The Horn River Basin well database comprises all available wells penetrating the pre-Cretaceous unconformity in the study area, 556 in total, including 43 wells confidential at the time of the study, but released to the study group by Horn River Basin Producers Group (HRBPG) members.
To establish a stratigraphic framework, 16 regional cross-sections were built. Correlations were established from the literature and previous studies, and were calibrated with observations from cores and sample cuttings. Logs from each well were tied to the cross-section grid to interpret stratigraphic tops, which were entered into a master stratigraphic database.
Cores were logged from 60 wells and all cores that appeared to provide significant reservoir or stratigraphic information were examined, omitting only a few short carbonate cores to the east and several Cretaceous sand/shale cores to the west.
Very few cores were cut in Mississippian carbonates within the Horn River Basin proper, and there is essentially no representation of the uppermost carbonate sections, which appear to have the best reservoir potential. Core coverage of Mattson reservoirs to the west is similarly scanty. A project was therefore commissioned, to systematically examine and document drill cuttings from Mississippian carbonates throughout the HRB, and from Mattson sandstone sections near HRBPG lands in the west. Sixty-three (63) wells were identified for the study by Producer Group members. John Clow (JC Consulting Inc.) examined cuttings across the prospective section in each, and performed semi-quantitative estimates of reservoir porosity and permeability. Jim Stepic (JMS Geological Consulting) prepared samples for standard petrography, SEM imaging, and XRD analysis, to provide additional reservoir characterization information.
Canadian Discovery Ltd. compiled well test data from public formation pressure and water chemistry databases, and also incorporated proprietary pressure, chemistry, and deliverability data provided by members of the HRBPG. Data were screened to ensure their validity, and hydraulic head, pressure over depth, available head, formation water chemistry, H2S chemistry, and resource volumes maps were created.
Permeability analyses were also completed, and used to estimate well deliverabilities.
Incorporating all these data and interpretations, PRCL produced regional maps of key stratigraphic surfaces and intervals throughout the aquifer section. Core and sample data were tied to logs to estimate reservoir quality, which was also systematically mapped. Finally, reservoir maps were combined with hydrogeological interpretations to generate a basin-scale aquifer characterization of each key unit.Return to Contents
Deep subsurface aquifers carrying saline waters are ideal sources and sinks for the water volumes required. Following upon successful completion of the Horn River Basin Deep Subsurface Aquifer Characterization Project, Geoscience BC commissioned Petrel Robertson Consulting Ltd. and Canadian Discovery Ltd. to undertake a similar study of deep saline aquifers in the Montney play fairway, as a component of the regional Montney Water Project. To date, operators in the Montney play have not made systematic use of deep subsurface water source or disposal capacity.
The fairway was divided into Plains and Foothills study areas, based primarily on subsurface stratigraphic and structural aspects. In the Plains, potential aquifers ranging from Middle Triassic Halfway to Upper Cretaceous Cardium were assessed. The best aquifer characteristics - thick net porous sandstones, high storativity, good to excellent potential deliverability, moderate to low salinities, and little or no H2S - were found in the Cadomin and Nikanassin aquifers. The Baldonnel, Bluesky, and Peace River formations offer more modest aquifer characteristics, but may still have local importance.
In the Foothills, potential aquifers range from the Mississippian Debolt to the Lower Cretaceous Bluesky; younger Cretaceous strata have shaled out in this area. In general, more extensive diagenetic degradation has reduced aquifer quality in the sandstone reservoirs, compared to the Plains Study Area. Aquifer quality in Debolt and Baldonnel carbonates is difficult to assess from logs, but test data indicate variable aquifer quality, with waters of moderate salinity and some H2S present. Foothills drilling and gas production are focused on the crests of regional northwest-southeast structural (anticlinal) trends, so there are insufficient data to adequately characterize aquifer quality off-trend.
Key observations arising from the project include:
(1) Deep subsurface aquifers with sufficient quality to support Montney water requirements are distributed unevenly across the play fairway; (2) The northern Plains Study Area contains substantial stacked aquifer potential, while there is much less potential in the southern Plains area, where a Deep Basin (gas-saturated) regime occurs in many of the units; (3) Good aquifer potential is present only in the southeastern Foothills area. More detailed work is required to determine whether gas production along regional anticlinal trends can be linked to fracturing, and whether such fractured reservoirs are capable of water production outside of established pool areas.Return to Contents