Present-day lysocline levels are determined for the west and east Tasman Sea according to the proportion of planktonic foraminiferal fragmentation in core-top samples. For the east Tasman Sea, the lysocline level occurs at -3100 m, whereas in the west Tasman Sea it occurs at -3600 m. Foraminiferal fragmentation patterns in deep-sea holes ODP 828, RC 12-113, DSDP 588, 591, 592, 593, E36-23 and E39-75 are not consistent with basin physiography, which brings into question the well-known Atlantic versus Pacific-Indian Ocean dissolution patterns for the Brunhes Chron. Although the corrosive Antarctic Bottom Water condition is the main cause for CaCO3 dissolution, organic matter flux and its metabolic oxidation in pore waters also has an effect on fragmentation patterns. Parallel trends between the fragmentation, and the planktonic delta (super 13) C records suggests that both are related and respond to a common cause, namely local surface productivity changes.