A nonmarine record of eccentricity forcing through the Upper Triassic of southwest England and its correlation with the Newark Basin astronomically calibrated geomagnetic polarity time scale from North America
David B. Kemp and Angela L. Coe, Neftex Petroleum Consultants Ltd, 115BD Milton Park, Abingdon, Oxfordshire OX14 4SA, UK. Pages 991-994.
Recent work by British geologists has, for the first time, allowed approximately 200-million-year-old rocks to be accurately correlated between Britain and America at a potential resolution of just a few thousand years. Kemp and Coe's findings may allow ancient rapid global climate changes, recognizable in the geological record, to be precisely constrained in time in order to prove the synchronicity of events. This work may be beneficial in improving estimates into the timing, rates, and causes of ancient rapid global warming events and mass extinctions.
Bryozoan paleoecology indicates mid-Phanerozoic extinctions were the product of long-term environmental stress
Catherine M. Powers and David J. Bottjer, University of Southern California, Earth Sciences, Los Angeles, California 90089-0740, USA. Pages 995-998.
Marine life suffered two devastating extinctions, at the end of the Permian and the end of the Triassic, 252 and 200 million years ago, respectively. Through a global survey of Permian through Early Jurassic bryozoan assemblages, Powers and Bottjer show that the end-Permian and end-Triassic mass extinctions were part of two protracted intervals of environmental stress that initially affected deep-water settings before encroaching onto shallow shelves and killing marine organisms living in the photic zone. These results are important as they suggest a long-term oceanographic, rather than extraterrestrial, mechanism for these biotic crises, an
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Geological Society of America