(Table 1) Stable-isotope and eolian grain size data across the Paleocene/Eocene boundary from DSDP Hole 22-215

Deep Sea Drilling Project (DSDP) Site 215 provides an expanded section across the Paleocene/Eocene boundary, the most complete mid-latitude sequence from a Southern Hemisphere location in the Indo-Pacific area. The events of this transition occurred during a span of about 1.2 m.y. Oxygen isotope values derived from benthic foraminiferal calcite decrease by about 1.0 per mil, a decrease most likely related to warming of deep ocean waters. Turnovers of benthic foraminifera accompany d18O changes and culminate in the predominant extinction event at the end of the Paleocene Epoch. Carbon isotope ratios also shift dramatically toward lighter values near the end of the Paleocene, beginning about 0.45 m.y. after oxygen isotope values start to change. The intensity of Southern Hemisphere atmospheric circulation as recorded by grain sizes of eolian particles shows a large and rapid reduction beginning another 0.45 m.y. later. A significant reduction of zonal wind strength at the Paleocene/Eocene boundary, until now observed only at Northern Hemisphere locations, appears to have been a global phenomenon related to decreased latitudinal thermal gradients occasioned by more effective poleward heat transport via the deep ocean.

(Table 1) Abundance of shocked quartz in K/T boundary sediments from DSDP Site 91-596

Sediments from the Cretaceous/Tertiary (K/T) boundary at Deep Sea Drilling Project Site 596 record accumulation of pelagic clays at about lat 45°S,in the center of the ancestral South Pacific. The K/T boundary in this region is characterized by oxidized, thoroughly bioturbated sediments containing large amounts of Ir and relict high-pressure and high-temperature mineral phases. The net Ir fluence (320 ng/cm**2) is among the largest on Earth, and the number of shocked quartz grains >30 µm in size (~1800/cm**2) exceeds that in all localities outside of North America.