Proceedings of the Ocean Drilling Program Volume 159T Scientific Results: Eastern Canary Basin, Site 958

This Scientific Results volume covers Leg 159T of the cruises of the Drilling Vessel JOIDES Resolution, Falmouth, England, to Dakar, Senegal, Site 958, 23 December 1994–3 January 1995.

In December 1994, the JOIDES Resolution entered drydock in Falmouth, England, for routine maintenance and refurbishment, five years after its previous drydock. After drydock, the Resolution sailed south to Dakar, Senegal, for the port call that began Ocean Drilling Program (ODP) Leg 159. The date for arriving at Dakar was fixed, but if drydock work finished earlier than scheduled, or if the transit speed was faster than estimated, the ship might have had as much as one or two days of extra time before arriving in port. Because of this possibility, plans were made to take some cores at a site of opportunity along the transit, instead of letting the ship sit idle off the coast of Senegal. Because of the short-term planning for this contingency, the site had to be positioned out of any countries' territorial waters, in an area with little chance of encountering hydrocarbon hazards. In addition, the site could not be too far off the ship's track to Dakar, and should preferably be located along or near previously existing seismic survey lines. A potential site was located at the crossing point of Glomar Challenger Line 14 and Vema Line V-2908. It was close to previously existing ODP sites drilled during Leg 108 (Sites 657 and 658), in water depths intermediate between them. Thus, it could provide complementary data to Leg 108 sites on paleoceanographic and paleoclimatic topics such as the history and nature of trade winds, surface water currents, and bottom water currents during the Neogene. Because only a short time might be available for drilling, only advanced hydraulic piston corer (APC) cores were planned to be taken. 

Extra time was indeed available during the transit, so a short presite survey was made and 15 APC cores in two holes were taken at Site 958. No scientists were aboard the ship during the transit, and only 24 hours elapsed before reaching Dakar after finishing the site, so the cores were sectioned, run through the multisensor track, and stored in the core reefer. After Leg 159, they were shipped back to the Gulf Coast Repository in College Station, TX, where they were split, described, and analyzed on shore.