Abstract

The Silverpit Crater consists of a set of concentric faults up to 20 km in diameter in the southern North Sea. Although formerly described as the first impact structure to be recognized in the UK, its spatial association with local tectonic and stratigraphic features suggests that it is unlikely to have been caused by a random extra-terrestrial event. This paper proposes a terrestrial origin for the Silverpit Crater as a Palaeogene pull-apart basin linked to strike-slip faulting in the Carboniferous basement. Faulting and thinning of Permian evaporites underlying the crater acted as a buffer to basement extension and caused both a flexural collapse of the overlying Triassic strata and circumferential listric faulting in the Cretaceous succession. Reactive diapirism in Lower Jurassic shales may have contributed to the formation of a central uplift at base Cretaceous level. The paper compares the tectonic setting of two contemporaneous strike-slip-related structures in southern England (Bovey Basin in Devon and the Compton Valence structure in Dorset) with that of the Silverpit Crater, and concludes by briefly considering whether a pull-apart model can help to explain the formation of Upheaval Dome, a similar putative impact structure in the Canyonlands National Park of Utah.

You do not currently have access to this article.