2000 Annual Science Report
Pennsylvania State University Reporting | JUL 1999 – JUN 2000
Evolution of Atmospheric O2, Climate, and the Terrestrial Biosphere: Approaches From Field-Oriented Geochemical Investigations - Lee R. Kump 3
Greg Retallack (University of Oregon ) has been diverted by funding for a variety of projects not relevant to PSARC, but he continues studies of Precambrian fossils, and reported on a new occurrence of Ediacara-like fossils from Montana at the Geological Society of America Meeting this past November. A manuscript was also completed with Doug Elmore, Monika Cogoini and Nathan Sheldon on using paleomagnetic susceptibility anomalies to recognize paleosols in late Precambrian fluvial successions. Work continues on small lichen-like fossils in the Waterval Onder paleosols (2.2 Ga). CAT-scanning of these fossils at the University of Texas provided good images at last. A new edition of the textbook “Soils of the past” was sent off to Blackwell, and this includes much of interest to PSARC, including the currently compelling case from isotopic studies for life in soils well back into the Precambrian.
PROJECT MEMBERS:Greg Retallack
RELATED OBJECTIVES:Objective 5.0
Describe the sequences of causes and effects associated with the development of Earth's early biosphere and the global environment.
Identify the environmental limits for life by examining biological adaptations to extremes in environmental conditions.
Define climatological and geological effects upon the limits of habitable zones around the Sun and other stars to help define the frequency of habitable planets in the universe.
Determine the resilience of local and global ecosystems through their response to natural and human-induced disturbances.
Model the future habitability of Earth by examining the interactions between the biosphere and the chemistry and radiation balance of the atmosphere.