Calcium carbonate undersaturation of bottom waters in the South Australian Basin during the last 3.2 million years.

Analyzed deep-sea benthic foraminifera from 3 Eltanin piston cores to infer deep-water circulation in the W South Australian Basin during the past 3.2 Ma. During the Gauss and early to middle Matuyama chrons, Epistominella umbonifera was the dominant species; Uvigerina spp. and Epistominella exigua increased in abundance during the late Matuyama, and became dominant during the Brunhes chron. During the Brunhes chron, cold, carbonate-undersaturated bottom water was replaced by bottom water having properties intermediate between present-day Antarctic Bottom Water and Circumpolar Deep Water. Comparison of our faunal data with previously published grain-size data indicates no direct relationship between bottom-water velocities and variation in cold, carbonate-undersaturated bottom water in the South Australian Basin. -from Authors

Duke Scholars

Author Bruce Corliss Earth and Climate Sciences