The regional Beaufort-Mackenzie Basin temperature field is characterized using data collected from drill-stem tests and bottom-hole temperature logs. We recognize two thermal anomalies, each of which is associated with a specific geological setting. Elevated temperatures are observed in (1) the western Beaufort Sea, where post-Eocene erosion removed Cenozoic strata and folding is common in a contractional tectonic regime, and (2) along fault zones where upward flow transports heat by advection. Depressed temperatures are observed in Eocene and post-Eocene rapidly subsiding depocenters, with overpressure developed below 3000 m (9843 ft). Older strata along the southeast rifted margin are characterized by a more normal thermal regime. Evidence from anomalously high temperatures in both map and cross-sectional views suggests that fault zones and major regional aquifers accommodate the upward expulsion of fluids from deep overpressured zones. Many significant petroleum discoveries occur in areas where anomalously high temperatures are observed, suggesting that petroleum migration occurs along the same flow networks. Identifying anomalies in the temperature field may therefore be a useful exploration technique.
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