The Geological and Geophysical Setting near DSDP Site 395, North Atlantic Ocean

Abstract

A very detailed geological and geophysical study of the ocean crust on the upper flank of the Mid-Atlantic Ridge, near 23 °N, 46 °W, was conducted in preparation for drilling a deep multiple re-entry IPOD hole. The site was chosen to sample crust that is spreading at a slow rate and is near zero age. The site survey was designed to delineate a specific spot of well-defined age, uncomplicated by fracture zones, with geological and geophysical characteristics typical for the region, and with adequate sediment cover to allow deep drilling. The prime site recommendation, at 22°45.2 / N by 46°07.3'W, fits these specifications. This target was also desirable because the bulk of the IPOD-sponsored survey data was centered around it, and a multichannel seismic reflection line traversed it. Alternative sites were also considered.