Physics Colloquium
Friday, September 17th, 2004, 4:00 P.M.

Troy Shinbrot

Department of Biomedical Engineering, Rutgers University

Granular flows in Martian geomorphological features

Over the last decade or more, contradictory evidence of Martian climate - indicating that surface temperatures seldom if ever approach the melting point of water at midlatitudes - and geomorphic features - consistent with liquid flows at these same latitudes - have proven difficult to reconcile.  In this talk, I will demonstrate that several features of liquid-erosional flows can be produced by dry granular materials when individual particle settling is slower than characteristic debris flow speeds.  Since the gravitational acceleration on Mars is about 1/3 that on Earth, and since particle settling speeds scale with gravity, I propose that some (though perhaps not all) Martian geomorphological features attributed to liquid flows may in fact be associated with dry granular flows in the presence of reduced gravity.