Major change in Atlantic deep and bottom waters 700,000 yr ago: benthonic foraminiferal evidence from the South Atlantic

Auteurs :
PETERSON, L. C.
LOHMANN, G. P.

Description :
Analysis of the benthonic foraminiferal faunas in two sediment cores recovered from the Vema and Hunter Channels in the western South Atlantic shows that the level of the transition between deep and bottom waters shallowed sharply about 700,000 yr ago. This rise indicates a sharp, sustained increase in the volume of bottom water flowing through the South Atlantic after this time. Prior to about 700,000 yr ago, the amount of Antarctic Bottom Water entering the western South Atlantic was greatly reduced and Circumpolar Deep Water apparently accounted for the bulk of northward flow. Production of southward-flowing North Atlantic Deep Water seems not to have been affected. The timing of this change in circulation regime suggests a possible causal link to similar changes in records of terrestrial and sea-surface climate.


Type de document :
Article de périodique

Source :
Quaternary research New York, 1982, vol. 17, n°. 1, p. 26-38, Références bibliographiques : 36 réf.

Date :
1982