Cooling and ice growth across the Eocene-Oligocene transition
Caroline Lear et al., School of Earth, Ocean and Planetary Sciences, Main Building, Park Place, Cardiff CF10 3YE, UK. Pages 251-254.
One of the most important climatic changes in Earth's history happened at the Eocene-Oligocene boundary (approximately 34 million years ago) when a thick ice sheet grew in East Antarctica. Previous temperature records found no evidence of ocean cooling at this time, which presented a confusing picture of the climate system. Lear et al. present new temperature records from the geochemistry of preserved fossils that show, for the first time, that the oceans did cool (by about 2.5 C) across the Eocene-Oligocene climate transition. These new records help resolve a long-standing puzzle regarding the extent of ice sheet growth versus global cooling, and bring the climate proxy records into line with the climate model predictions.
Earths copper resources estimated from tectonic diffusion of porphyry copper deposits
Stephen Kesler, Department of Geology, University of Michigan, Ann Arbor, Michigan 48109, USA; Bruce Wilkinson, Department of Earth Sciences, 222 Heroy Geology Laboratory, Syracuse University, Syracuse, New York 13244-1179, USA. Pages 255-258.
Kesler and Wilkinson provide the first estimate of the to
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Geological Society of America