Rock-Eval data for four hydrocarbon exploration wells in Hudson Bay and Foxe basins

Abstract

Hudson Bay and Foxe basins are Lower Paleozoic sedimentary basins in the eastern Canadian Arctic. Hydrocarbon exploration of these two basins began more than 30 years ago, however, their hydrocarbon potential remains poorly understood. In Hudson Bay Basin, the lower part ofthe Paleozoic succession comprises 600 to1040 m of Upper Ordovician (Bad Cache Rapids and Churchill River groups and Red Head Rapids Formation) and Lower Silurian (Severn River, Ekwan River, Attawapiskat and Kenogami formations) carbonate and minor amounts of shale. The Paleozoic sequence in Foxe Basin is composed of ~ 510 m of Middle Cambrian (Gallery and Turner Cliff formations), Middle and Upper Ordovician (Frobisher Bay, Amadjuak, Akpatok and Foster Bay formations) and Lower Silurian (Severn River Formation) sandstone, carbonate and minor amounts of shale. A total of 246 samples, collected from 4 wells (Polar Bear C-11 and Narwhal South O-58 in Hudson Bay offshore, Comeault No. 1 on Hudson Bay Lowlands, and Rowley M-04 in Foxe Basin), were analyzed using Rock-Eval 6 Pyrolysis technique. The new data from Hudson Bay demonstrate that: 1) At Narwhal South O-58, samples from the middleupper Bad Cache Rapids Group have Tmax between 431 and 436. The total organic carbon (TOC) is uniformly very low. 2) At Polar Bear C-11, almost all samples from the Bad Cache Rapids Group to middle Severn River Formation have a Tmax between 430 and 440; however, the TOC is uniformly low. 3) At Comeault No. 1, more than half of the samples from Bad Cache Rapids Group to Severn River Formation show a HI>300, and several samples have TOC>2%. However, most of the samples have Tmax<435 and are below the threshold for hydrocarbon generation. 4) At Rowley M-04 strata show some elevated TOC but insufficient thermal maturity for hydrocarbon generation.