Abstract

Available core, borehole, seismic, gravity, aeromagnetic and palynological data are combined with field data to reconstruct the Visean tectonostratigraphy and architecture of the Central Basin of New Brunswick, which is mainly hidden below the New Brunswick Platform, an unconformable cover of Pennsylvanian rocks. The Visean Central Basin is separated from the contemporaneous Ristigouche Basin of northern New Brunswick and eastern Quebec by the Bathurst Horst, a buried Visean basement high. Like in the Ristigouche Basin, erosional remnants of the La Coulee Calcrete occur in the Central Basin below coarse red conglomerates of the Bonaventure Formation, which were previously not correlated with this unit. This suggests the nearby presence of an evaporitic basin at the time of phreatic calcrete hardpan formation, a period of uplift and erosion, and subsequent burial by continental clastics, which were probably controlled by active faulting at the margin of the basin. As opposed to the Ristigouche Basin, the Bonaventure Formation includes a volcanic interval in the Central Basin. The latter basin was affected by faulting, uplift, tilting and erosion during Yeadonian to Duckmantian times, which generated an angular unconformity with overlying younger rocks. Synchronous to most of this deformation, the Yeadonian to Duckmantian Red Pine Brook Formation was deposited in the Bathurst Subbasin, which partly overlaps the Central Basin, and which is composed of reworked Mississippian rocks that were sourced from both the latter basin and the Ristigouche Basin.