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Project Progress

Impact Frustration and Subsequent Generation of Biologically Tenable Climates on Earth and Mars (dm)

Mars is a water rich planet. Impact vaporization and melting studies of Mars subsurface H2O ice and computer simulation of crater ejecta demonstrate that most of the subsurface material sampled by visible impact craters appears to have contained some 5-30% by volume of water ice, indicating that the water mass on Mars is at least 3.9 ×10-4 times the mass of the planet. This compares to 2.8 × 10-4 in the case of the Earth.

Our analysis of the global acidification that occurred at the K/T boundary indicates that ~1 × 1017 equivalents of strong acid was deposited on the continents. We conclude that North America was preferably leached with greater densities of acid from prompt fallout of H2SO4 aerosol.

Shock temperatures measured in crystal calcite in the 95-160 GPa range yield radiative temperatures of 3300 to 5400 K. Calculations indicate that the temperatures are 400 to 1350 K lower than predictions indicating massive bond breakage under pressure. Calcite therefore decomposes upon unloading from only 18 GPa.