The morphology of lava flows in planetary environments

Abstract

The rates of surface cooling and lateral spreading are evaluated for lava flows on the surface of Earth, Venus, Mars, the Moon, and Io. Differences between the flow morphologies expected in these environments are then predicted under the assumption that the results of recent laboratory simulations of lavas using wax extruded beneath cold water can be carried over. Transitions from one morphology to the next occurred in a well-defined sequence when the relative rates of surface solidification and lateral spreading were varied. A comparison of observed structure, flow rates, and estimated viscosities for some well-documented terrestrial lava flows shows reasonable agreement with the predictions of the model. Extrapolation to extraterrestrial lavas is then illustrated by constraining the effusion rate for a Martian lava flow whose composition is assumed. -from Authors Show more