Initial Reports of the Deep Sea Drilling Project - Volume 54

This volume covers Leg 54 of the cruises of the Drilling Vessel Glomar Challenger. The Pacific phase of IPOD ocean crust drilling was initiated with Leg 54, the region targeted for study by the Ocean Crust Panel being survey area PT-4 north of the Siqueiros fracture zone on the western flank of the East Pacific Rise (EPR). The original purpose of this leg was to establish a type section for fast-spreading, nonrifted crust by direct sampling with stratigraphic control. We anticipated that this section would serve, in part, as a standard of comparison for other type sections, such as the Mid-Atlantic Ridge (MAR). The Glomar Challenger left Cristobal, Panama, on the morning of 30 April 1977, to begin transit through the Panama Canal. The ship arrived in San Pedro, California, on the morning of 18 June 1977. During Leg 54, the ship traveled 6333 nautical miles, occupied 11 sites, attempted to drill 18 holes, and successfully penetrated basement at 13 localities.