PSI SEMINAR SERIES: 29 October 2008, 11:00 AM
The Evolution of Mars, a Perspective from SNC Meteorites
Audrey Bouvier
(Arizona State University)
The Earth, Moon, and Mars are the only three planets for which satellite and ground observations can be confronted with extensive chronological and geochemical observations of rock samples. The true crystallization age of shergottites, the most common group of the Martian SNC meteorites, is currently not agreed upon. Although most of the radiogenic chronometers such as Rb-Sr or U-Pb give very young ages, in the range of 150-550 Ma, 207Pb-206Pb ages support a much older crystallization age at 4.1 to 4.3 Ga. Different isotopic systems present different complexities but also new clues about the SNC chronology, and thus the history of Mars. I will compare the geochemical footprints with crater-counting chronology, terrestrial equivalents, and ground and geophysical observations and show how it leads toward a vigorous scenario for the evolution of the red planet.
