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2002 Annual Science Report

Harvard University Reporting  |  JUL 2001 – JUN 2002

Executive Summary

The study of the ways in which Earth’s first environments originated and evolved is, to a large extent, a study of the history of oxygen. The planet’s most abundant element, oxygen occurs in Earth’s crust, in its freshwater, in its seawater, and in its atmosphere; it is of quintessential importance to virtually all life. Practically all Earth’s free oxygen was formed as a result of photosynthetic processes carried out by cyanobacteria and the early plants, processes through which organic compounds are synthesized from carbon dioxide and water in the presence of sunlight.

The Harvard NAI team was constituted in 1998 as an interactive group of biogeochemists, paleontologists, sedimentary geologists, geochemists, and tectonic geologists assembled with the common goal of understanding the coevolution of life and environments in Earth history. The team originally proposed to focus multidisciplinary research on four critical intervals of planetary change: (1 ... Continue reading.

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