| Title | Assessing baseline near-surface bedrock and groundwater geochemical data prior to shale gas exploration and development - the case of the Utica Shale, Quebec, Canada |
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| Author | Lavoie, D ; Mort,
A; Haeri Ardakani, O; Sanei, H; Bordeleau, G; Rivard, C; Aznar, J C |
| Source | Goldschmidt 2014, abstracts; 1370, 2014 p. 1  Open
Access |
| Links | Online - En ligne
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| Image |  |
| Year | 2014 |
| Alt Series | Earth Sciences Sector, Contribution Series 20130388 |
| Publisher | Goldschmidt |
| Meeting | Goldschmidt 2014; Sacramento, CA; US; June 8-13, 2014 |
| Document | book |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Quebec |
| NTS | 21L; 31H; 31I |
| Area | St. Lawrence Platform |
| Lat/Long WENS | -75.0000 -71.0000 46.7500 45.0000 |
| Subjects | fossil fuels; hydrogeology; geochemistry; environmental geology; Nature and Environment; Science and Technology; hydrocarbons; hydrocarbon potential; groundwater; groundwater resources; groundwater
pollution; groundwater geochemistry; environmental analysis; environmental studies; environmental impacts; Utica Shale |
| Program | Geoscience for New Energy Supply (GNES) |
| Program | Environmental
Geoscience Shale Gas - groundwater |
| Released | 2014 06 01 |
| Abstract | In eastern Canada, the Utica Shale is a potential shale gas producer. In 2010, exploration came to a halt pending an environmental review. The Geological Survey of Canada has initiated a bedrock and
groundwater-focussed pilot research project near Quebec City. Twenty-five private water wells were sampled and 4 shallow (50 m) wells were drilled, cored and sampled for water chemistry and rock organic geochemistry. In addition, 250 sites were
sampled for pore-space radon and hydrocarbons in soils.
The shallow bedrock geology is dominated by Upper Ordovician shales and sandstones. Rock-Eval and organic matter reflectance results suggest that thermal maturity increases southerly from oil
to condensate windows. GC and GC-MS analyses of core extracts document the presence of low but detectable concentrations of C1 to C20 hydrocarbons.
Most water samples have significant concentrations of dissolved hydrocarbons including mostly
methane, as well as ethane and propane in a few wells. The presence of dissolved hydrocarbons in groundwater is fairly well established in southern Quebec, although their source (biogenic versus thermogenic) remains ambiguous. The presence of
dissolved propane indicates that some of the hydrocarbons are thermogenic in origin. Gas wetness and isotopic ratios (d13C, d2H) of methane suggest mixed thermogenic and biogenic origin. Areas with elevated radon, methane, ethane and butane in soils
are associated with the tectonized Appalachian deformation front, a sector with high concentrations of hydrocarbons dissolved in groundwater. |
| Summary | (Plain Language Summary, not published)
This abstract will present preliminary geochemical data in groundwater, soils and bedrock that were gathered up to now in this project (Environmental
Geoscience and Geoscience for New Energy Supply programs). One of the goals of the study is to identify the source of gas present in groundwater in the St. Edouard de Lotbinière (65 km SW of Quebec City). Some preliminary ideas are considered but
without certitude so far. This will be explained in the presentation |
| GEOSCAN ID | 293456 |
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