Limited data are also available for planktonic foraminifers over the same intervals.
There is strong orbital-frequency covariance between in bulk fine fraction and in benthic foraminifers, suggesting that both parameters reflect variability in the of dissolved CO2 in the ocean. Spectral analysis of the whole record for bulk fine fraction shows strong power in the 400-k.y. 2 University of Cambridge, Godwin Laboratory, Free School Lane, Cambridge, CB2 3RS, United Kingdom.