Examination of eolian sediments from deep-sea cores has revealed evidence for a significant reduction in the intensity of atmospheric circulation that occurred over a span of 1-2 my in the temporal vicinity of the Paleocene/Eocene Epoch boundary. Early Eocene winds were much more sluggish than the surprisingly strong winds of the latest Cretaceous Period and Paleocene Epoch, and implicate a significant reduction in the planetary temperature gradient. In a sequence of longer-term changes that occurred over approximately 3 my beginning in the late Paleocene Epoch (from Biochron P4 to P6), the onset of ocean deep-water warming (based on delta (super 18) O data) preceded the beginning of changes in the partitioning of carbon between ocean and sedimentary reservoirs (based on delta (super 13) C data), which preceded the start of a pronounced reduction in wind intensity, which preceded the benthic foraminifera extinction. These four events were spaced roughly one-half to one million years apart. Explanations for this rather drawn-out series of changes, particularly considering the order in which they occur, are not yet fully satisfactory. The introduction to the ocean-atmosphere system of another greenhouse gas, methane, may be more important than previously considered.

West: 157.4323 East: 164.1633 North: 32.2632 South: 32.2121

Expedition: 86

Site: 86-576

Site: 86-577

Provider: SEDIS Publication Catalogue

Data set link: http://sedis.iodp.org/pub-catalogue/index.php?id=2000-031859 (c.f. for more detailed metadata)

This metadata in ISO19139 XML format