Subsidence of the Atlantic-type continental margin off New York

The continental margin off New York consists of a thick sequence of at least 4.8 km of mainly shallow-water sediments. Such large thicknesses of shallow-water sediments cannot be produced by the effects of sediment loading alone. We have used biostratigraphic data from the COST B-2 well to examine the origin of the subsidence of this margin. The contribution of sediment loading to the subsidence has been evaluated and removed. Corrections for effects of compaction, water depth and changes of sea-level were also included. The remaining subsidence has been interpreted in terms of a simple thermal model for the cooling lithosphere. Based on this model a thickness of the thermal lithosphere of 113–139 km is estimated. The total subsidence and crustal thinning beneath the COST B-2 well are also estimated and used to place constraints on models for the origin of the margin.