Fossil Contourites in Lower Niesenflysch, Switzerland

Abstract

ABSTRACT The lower part of the Maastrichtian-Paleocene Niesenflyseh near Adelboden, Switzerland, consists of shale and shale--sandstone alternations. The sandstone beds normally are 4 to 5 cm thick, have distinct upper and lower bedding planes and are rather well sorted. The only primary sedimentary structures are parallel lamination and some foreset bedding. Although these two sedimentary structures are known from turbidites, the absence of diagnostic vertical successions are indicative of processes other than turbidity current deposition. The series is believed to be deposited by turbidity currents and normal pelagic sedimentation. The sandstone beds are interpreted to be fossil contourites: local reworking by contour--following bottom currents.