University of Arizona planetary geologist Victor Baker [
photo credit GSA] is getting ready to launch his
International Distinguished Lecture Tour for the Geological Society of America. In May, Vic will be lecturing in Spain, Italy, and Turkey. His topics are described below:
Megafloods on Earth, Mars, and Beyond
For more than 40 years University of Arizona Regents’ Professor Victor R. Baker has been studying the most spectacular and immense flood phenomena currently known to occur anywhere in the solar system. The immense megafloods of the last Ice Age created bizarre landscapes like the Channeled Scabland and altered the circulation of the oceans thereby changing Earth’s climate. More surprising was the discovery that much larger megafloods occurred billions of years ago on the planet Mars. The Martian megafloods formed temporary bodies of water on that planet, even generating a kind of ocean that facilitated environmental conditions on Mars that may have been like those of an ice age on Earth. These discoveries are showing that Mars, like Earth, had a long-term cycle of water circulation that produced a habitable planet, and these are exactly the kinds of processes to seek out in the newly initiated search for the other habitable planets of the universe.
Geological History of Water on an Earth-like Planet
Recent advances in astronomy hold the prospect for discovery of a great many Earth-like planets, rich in both water and possible habitats for life, thereby greatly expanding from the current sample of one. Nevertheless, until it proves possible to do geology for these numerous potential exo-Earths, we can greatly advance the geological science of Earth-like planets by study of Mars. The early geological histories of both Mars and Earth are closely tied to the role of water, extending from the nature of planetary accretion to the origin of a physically coupled atmosphere and ocean, the prospects for initiating plate tectonics, and historical records of punctuated greenhouse-to-icehouse climatic transitions. Recent discoveries from Mars missions reveal the extensive role of water in generating sedimentary rocks, active and relict glacial and periglacial features, aqueous weathering products (clay minerals and sulfates), alluvial fans and deltas, the extensive development of paleolakes, and even a probable, though transient ocean.
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