SLAS Regular Meeting
Friday, November 21
7:30 pm

The Evolution of Volcanism on Venus

by

Christopher Orth
Washington University

  The planet Venus sparkles in the western sky of early evening as twilight deepens. It is nearly the twin of the Earth in size, but an un-identical twin in terms of its atmosphere and surface. The surface of Venus is always hidden from view, even by orbiting space craft, due to its thick, unbroken layer of clouds. Radar, however, can pierce the clouds and map surface features. One of the most striking discoveries of the radar images is the presence of craters, formed by meteoroid impacts. Mr. Orth will explain why the number of craters and their locations suggest that the surface of Venus is geologically young – “only” 300 million to 1 billion years old. He will also present some current theories that maintain that Venus has been resurfaced on a global scale, due to volcanism or to regional motion of its crust. Because evidence of volcanic action is so widespread, it could be that Venus is reaching the end of a period of massive lava flows. Mr. Orth will show how a simple model can account for the evolution of volcanism on the surface of Venus.
    Christopher Orth is a Doctoral candidate in the Department of Earth and Planetary Sciences at Washington University.  His research interests are focused on the structure and evolution of the interior of Venus, and how changes in the interior affect the surface.