Pardee Keynote Symposium - P1

Early Paleoproterozoic (2.5–2.0 Ga) Events and Rates: Bridging Field Studies and Models

Conveners: Andrey Bekker, Mark E. Barley, Robert H. Rainbird

The period 2.5-2.0 Ga saw some of the most dramatic and profound changes in Earth history. A global peak in volcanic activity coincided with deposition of iron formations and was succeeded by orogeny, three ice ages, the rise of atmospheric oxygen and a positive carbon isotope excursion in seawater composition. The end of the carbon isotope excursion also corresponds with the deposition of Mn-deposits, phosphorites, iron formations, and organic-rich shales. This symposium will bring together field-oriented and modeling studies focused on relationships between tectonics, changes in atmosphere and ocean composition, and climatic changes as well as the rates of these changes.

Red beds in the upper part of the Gowganda Formation (Firstbrook Member of the Gowganda area) immediately above the last of three glacial diamictites of the Paleoproterozoic Huronian Supergroup, Ontario, Canada (photo by A. Bekker, 70 cm long hammer for scale).


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2004 GSA Annual Meeting
Geoscience in a Changing World

November 7-10, 2004
Colorado Convention Center
Denver, Colorado