Site 656: de Marchi seamount.

Abstract

Site 656 is located on the western flank of the de Marchi seamount. The main objective was to date the syn-/pre-rift contact (which drilling at sites 652 and 654 was unable to do) and also to study any Messinian and pre-Messinian sediments that might be encountered. The first hole was abandoned when the pipe stuck in syn-rift sand and gravel, and the second was terminated to leave for Marseille; neither hole was logged. Four sedimentary units were recovered, ranging in age from pre-Pliocene to plate Pleistocene. Units I and II were deposited in normal, open marine conditions, unit III represents a transition from open marine to continental conditions, and the pre-Pliocene unit IV is clearly continental in origin.-A.W.Hall