| Title | The persistence of brines in sedimentary basins |
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| Author | Ferguson, G; McIntosh, J C; Grasby, S E ; Hendry, M J; Jasechko, S; Lindsay, M B J; Luijendijk, E |
| Source | Geophysical Research Letters vol. 45, issue 10, 2018 p. 4851-4858, https://doi.org/10.1029/2018GL078409  Open Access |
| Year | 2018 |
| Alt Series | Natural Resources Canada, Contribution Series 20170385 |
| Publisher | American Geophysical Union (AGU) |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf; html |
| Subjects | sedimentology; geochemistry; hydrogeology; sedimentary basins; brine; geological history; burial history; depositional history; fluid dynamics; bedrock geology; lithology; sedimentary rocks; evaporites;
traps; groundwater; groundwater movement; groundwater regimes; groundwater geochemistry; sea water geochemistry; salinity; Phanerozoic |
| Illustrations | models; geoscientific sketch maps; profiles; bar graphs; graphs |
| Program | Geoscience for New Energy Supply (GNES) Geothermal Energy |
| Released | 2018 05 08 |
| Abstract | Brines are commonly found at depth in sedimentary basins. Many of these brines are known to be connate waters that have persisted since the early Paleozoic Era. Yet questions remain about their
distribution and mechanisms for retention at depth in the Earth's crust. Here we demonstrate that there is insufficient topography to drive these dense fluids from the bottom of deep sedimentary basins. Our assessment based on driving force ratio
indicates that sedimentary basins with driving force ratio > 1 contain connate waters and frequently host large evaporite deposits. These stagnant conditions appear to be relatively stable over geological time and insensitive to factors such as
glaciations, erosion, compaction, and hydrocarbon generation. |
| Summary | (Plain Language Summary, not published)
Sedimentary basins in Canada can have a strategic value for isolating fluids and wastes from the atmosphere and more active parts of the hydrosphere.
These basins have received large volumes of produced waste water from the oil and gas industry, and have more recently become targets for carbon sequestration and nuclear waste storage. Demonstration that fluids in deep sedimentary basins are stable
over geologic time scales thus becomes critical to assessing waste storage proposals (e.g. ~1 million years is a requirement for nuclear waste based on radioactive half lives of critical nuclides). We developed a novel methods to assess long-term
stability of deep basin fluids. The findings demonstrate the potential for long-term sequestration of wastewater and anthropogenic CO2 in deep basins and provide insight into the maximum depth of low TDS groundwater in sedimentary basins. |
| GEOSCAN ID | 308076 |
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