The Western Boundary Undercurrent is a high-velocity, contour-following bottom current that flows southwesterly on the U.S. Atlantic continental margin. A high-velocity core of the Western Boundary Undercurrent is delineated by an analysis of underlying sediments, which are characterized by coarse particle sizes and efficiently aligned magnetic grains in a… (More)
The fabric and texture of deep-sea sediments have been used to detect periods of high-velocity bottom-water flow through the Vema Channel in the south-west Atlantic Ocean. In addition, the alignment of the long axis of magnetic grains has been used to indicate the direction of bottom-water flow.
Particle size analyses of surface sediments in the Vema Channel reveal a spatial variation related to the present hydrography. Similar analyses of sediment deposited during the last ice age (18,000 years before the present) indicate a maximum shallowing of the upper limit of Antarctic Bottom Water (AABW) of about 100 meters, coupled with an increase in… (More)
Acknowledgements The authors are grateful to the following individuals who provided data and analysis support for this report: