Skip to Main Content

Abstract

The Vema contourite fan is a Neogene mud-rich accumulation (200-400 m thick), fed by Antarctic Bottom Water bottom currents and located downstream of the Rio Grande Rise. It forms one single, mounded, fan-shaped body deposited between two major channels through which the main part of the deep AABW circulation is funneled. A suite of cores and seismic lines have been collected over the whole area. The sediments deposited below the shear zone between the two current branches consist almost exclusively of muddy contourites, either homogeneous in structure or micro-brecciated. Manganiferous deposits occur in the vicinity of the channels and on the channel floors. As a result of the morphological and hydrological background, the contourite drift has prograded mostly downstream. It is composed of several depositional units bounded by widespread discontinuities showing erosional patterns. This geometry results from an alternation of episodes of strong and unstable erosive currents, and periods of relatively weak and stable depositional currents

You do not currently have access to this chapter.

Figures & Tables

Contents

GeoRef

References

Related

Citing Books via

Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal