Initial Reports of the Deep Sea Drilling Project - Volume 47 Part 1

This volume covers Leg 47, Part 1 of the cruises of the Drilling Vessel Glomar Challenger. Glomar Challenger departed from Las Palmas, Gran Canaria, Canary Islands, on 20 March 1976, drilled two holes at Site 397, and arrived at Vigo, Spain, on 12 April 1976. The major objective of Leg 47A was to decipher the complex Cretaceous and Tertiary history of a flexure passive continental margin, for which the West Saharan segment between the Requibat Uplift (Cape Blanc) and the Canary Islands (Cape Juby) is a good example. The subsiding edge of this margin has experienced major episodes of erosion, non-deposition, and redeposition, especially during two major regressions (mid-Cretaceous and mid-Tertiary). The thick wedge of uppermost continental rise sediments off northwest Africa had never before been penetrated beyond the Neogene (DSDP Site 139). DSDP Site 369, on the continental slope nearby, served as an ideal companion site of our proposed drilling program for rise-slope comparisons. The planned site was expected to allow a better reconstruction of the history of uplift and subsidence, transgressions and regressions, mechanics of deposition, and erosion during the Early Cretaceous to Neogene.