| Title | Determination of geothermal gradient from borehole temperature and permafrost base for exploration wells
in the Beaufort-Mackenzie Basin |
| Download | Downloads |
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| Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
| Author | Hu, K ; Chen, Z; Issler, D R |
| Source | Geological Survey of Canada, Open File 6957, 2014, 23 pages, https://doi.org/10.4095/293872  Open Access |
| Year | 2014 |
| Publisher | Natural Resources Canada |
| Document | open file |
| Lang. | English |
| Media | digital; on-line |
| File format | pdf |
| Province | Northwest Territories |
| NTS | 107A; 107B; 107C; 107D; 107E; 107F; 117A; 117B/01; 117B/08; 117B/09; 117B/16; 117C/01; 117C/08; 117C/09; 117C/16; 117D; 117E |
| Area | Mackenzie River Delta; Beaufort Sea |
| Lat/Long WENS | -141.0000 -129.0000 71.0000 68.0000 |
| Subjects | surficial geology/geomorphology; geothermal energy; geothermal gradient; geothermal potential; ground temperatures; geothermal temperatures; permafrost; freezing ground; ground ice; heat flow;
Beaufort-Mackenzie Basin; Cenozoic; Quaternary |
| Illustrations | location maps; stratigraphic sections; tables; plots; stratigraphic columns; histograms |
| Program | GEM:
Geo-mapping for Energy and Minerals Mackenzie Delta and Corridor |
| Released | 2014 05 16 |
| Abstract | (Summary)
Geothermal gradient is a useful parameter for constraining models of heat flow and petroleum generation in sedimentary basins. This report documents geothermal gradient values for
the exploration wells that were used to construct a geothermal gradient map for the Beaufort-Mackenzie Basin. First-order, linear geothermal gradients were calculated for 259 Beaufort-Mackenzie petroleum exploration wells using subsurface temperature
data obtained during well testing and logging. Geothermal gradients were determined by applying a least-square fit to the deep temperature data with the requirement that they intersect the mapped base of permafrost at an assumed temperature of 0 ºC.
Geothermal gradient values were quality-assessed based on the quality and quantity of the individual temperature points used for the calculations and the quality of the fit to the data as represented by the coefficient of determination. Results are
displayed graphically as plots of temperature versus depth with respect to fitted linear geothermal gradients for specific well locations. Examples are used to illustrate some anomalous temperature data that have been excluded from the calculation of
geothermal gradient. For example, anomalously low DST temperature values in gas zones can be attributed to the Joule-Thomson effect related to gas expansion caused by the pressure drop that accompanies flow. Calculated geothermal gradients vary from
approximately 15 °C/km to 48 °C/km across the Beaufort-Mackenzie Basin, and a large fraction of the basin is characterized by typical sedimentary basin geothermal gradients of 25 °C/km to 35 °C/km (> 200 wells). |
| Summary | (Plain Language Summary, not published)
This report documents geothermal gradient values and their quality assessment for 259 petroleum exploration wells that were used for constructing a
geothermal gradient contour map for the Beaufort-Mackenzie Basin. First-order, linear geothermal gradients were determined by applying constrained least-squares fits to the deep temperature data obtained during well testing and logging with the
requirement that they intersect the mapped base of permafrost at an assumed temperature of 0 ºC. Geothermal gradient values were quality-assessed based on the quality and quantity of the individual temperature points used for the calculations and the
quality of the fit to the data as represented by the coefficient of determination. Calculated geothermal gradients vary from approximately 15 °C/km to 48 °C/km across the Beaufort-Mackenzie Basin, and a large fraction of the basin is characterized by
typical sedimentary basin geothermal gradients of 25 °C/km to 35 °C/km (> 200 wells). |
| GEOSCAN ID | 293872 |
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