Environmental implications of infillings in the Upper Greensand of the Beer District, South Devon

Abstract

The numerous crevice, fissure, and pocket deposits in the top part of the Upper Greensand of the Beer District are classified into six types. A correlation of these infilling deposits to the Cenomanian deposits is presented. Depositional and tectonic structures are described and an environmental interpretation is attempted. The presence of these infillings suggests that a relatively full Cenomanian succession was deposited in the area of Beer Ridge being represented by both the Cenomanian Limestone and sandy facies; i.e. it was an area of interdigitation. The deposits were subsequently eroded away due to various phases of tectonic uplift of the Beer Ridge, which continuously changed the bathymetric and dynamic conditions of the area causing repeated reworking of the sediments. The final deposition of the reworked heterochronous deposits as a lithoclastic limestone only occurred because transgression outpaced the rate of uplift on the ridge.