In the 1950's as seismologists began to assemble detailed elastic velocity versus depth models of the Earth, the subject of the physical properties of minerals at the high pressure and high temperatures of the Earth's interior began to receive considerable attention. This area of geophysics research, now called mineral physics, has historically been concerned with supplying information on mineral properties to allow the seismic velocity versus depth profiles in the Earth to be interpreted in terms of composition, mineral structure, and temperature. In 1967, upon the arrival of Tom Ahrens at the Seismological Laboratory, a laboratory was established to study the dynamic compression of minerals. Pressure-density-temperature, or equations of state are of interest. Important contributions to research on equations of state of Earth and planetary materials were made by Professors George Rossman and Edward Stolper. Drs. Paul Asimow and Jed Mosenfelder are now engaged in research on equation of state properties of high pressure phases of mantle minerals. Within several years the scope of research was enlarged to study the effects of shock deformation on minerals and rocks, shock pressure-induced phase changes (e.g. transformation of carbon in the graphite phase to the diamond phase and shock consolidation of powders). Later added were research programs on calculating the energetics and impact cratering from meteorite impacts on planetary surfaces. Previously, contributions to this research were made by Drs. John Dugan O'Keefe, James Tyburczy, Manfred Lange, and William Anderson. More recently, programs have been started to build instruments to measure physical and chemical properties of planetary surfaces and upon collision with cosmic dust and planetary ring material. Prof. Jesse Beauchamp has been a collaborator in much of our instrumental effort.
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