SEDIMENTATION IN THE ROMANCHE DEEP (A CONTRIBUTION TO THE EXPLANATION OF THE GENESIS OF THE DEEP-SEA SANDS IN THE ATLANTIC OCEAN)

Abstract

Sediments cored from the Romanche Deep in the Atlantic Ocean consist of globigerina mud containing foraminifer fragments; red clay with interbedded sand lenses; sands composed of plagioclase, pyroxene, quartz, serpentine, olivine, chlorite, and other minerals; and a "detrital globigerina ooze." Mineralogic and paleontologic examination indicate that the need for a continental source and extended horizontal transportation in suspension streams may be exaggerated. Although the theory that these deep-sea sands are products of continental weathering deposited in the deep after some thousands of kilometers of horizontal transportation and that suspension streams play an important role as the agent of transportation, redeposition, and configuration of the deep-sea sediments, it is possible that the sands in the Romanche Deep were derived, at least in part, from the Middle Atlantic Ridge. Therefore, deep-sea sands can provide valuable information on the composition of the submarine ridge and the mechanism of tectonic movement. --G. E. Denegar.