Fossil contourites: type example from an Oligocene palaeoslope system, Cyprus

Abstract

Abstract As part of a wider programme on the recognition and decoding of contourite sediments, we propose the adoption of part of the Lefkara Formation on Cyprus as the first in a series of type examples of fossil contourites in ancient series exposed on land. A clear case can be made for interpreting these mainly Oligocene age sediments as carbonate-rich contourites. They combine faint structures due to current action with pervasive bioturbation, typically show cyclic grain size alternation, and have compositional differences from the more easily identifiable calciturbidites. One particularly diagnostic contourite facies is a lenticular, thin-bedded calcarenite-cacisiltite from which the finer bioclastic material and terrigenous clays have been winnowed away. This facies is a well developed condensed unit, which occurs at the same stratigraphic interval throughout Cyprus. Variations in thickness and rates of sedimentation of the contourite units, as well as the presence of widespread hiatuses and alongslope palaeocurrent trends are consistent with drift development on a lower slope apron in the closing Tethys ocean.