The Moncton subbasin of southern New Brunswick forms the southwestern corner of the Carboniferous Maritimes Sedimentary Basin, which underlies much of the Gulf of St. Lawrence and outcrops in all four Atlantic provinces. The subbasin includes the only productive oil and gas field in the Maritimes.
Seismic reflection data collected by industry in southern New Brunswick is being interpreted in light of recent surface geological mapping and field data, with the goal of better understanding the tectonic evolution of the basin.
Preliminary results indicate that Carboniferous rocks have undergone at least three distinct phases of deformation in the Permo-Carboniferous: extensional faulting in the Late Devonian to Tournasian; compression evidenced by basin inversion during late Tournasian or early Visean time; and segmentation of the subbasin by strike–slip faults, which have moved since the early Westphalian. Timing of major fault movements, and structural styles observed, are compared to those found in fault-bounded subbasins at the opposite end of the Maritimes Basin, in western Newfoundland.
