Twenty-seven surface samples ofbiogenic sediment, including radiolarian, nannofossil, and foraminiferal oozes from the Western Equatorial Pacific have been analyzed for potassium, magnesium, iron, rubidium, strontium, barium, chromium, cobalt, nickel, copper, and zinc by rapid instrumental techniques. Interelement associations have been evaluated with the use of a computer-compiled matrix of co...

Ocean Drilling Program (ODP) Leg 199, “The Paleogene Equatorial Transect” (Sites 1215 through 1222), was designed to study the evolution of the equatorial Pacific current and wind system as the Earth went from maximum Cenozoic warmth to initial Antarctic glaciations. The drilling program was primarily devoted to a transect along 56to 57-Ma crust, old enough to capture the Paleocene/ Eocene boun...

The shutdown of carbonate productivity and its replacement by black shale deposition is often observed in the geological record yet factors driving such a change are debated. latest Famennian western Laurentia (present day North America) provides good example limestone – transition that roughly contemporaneous with global Hangenberg Crisis series environmental biotic changes associated widespre...

Both the duration and severity of deep-water anoxic conditions across Permian-Triassic mass extinction (PTME) are controversial. Panthalassa Ocean circulation models yield varying results, ranging from a well-ventilated deep ocean to rapidly developing northern-latitude, but not southern-latitude, anoxia in response Siberian Traps–driven global warming. To address this uncertainty, we examined ...