Fluid outflows from Venus impact craters: Analysis from Magellan data
Article first published online: 21 SEP 2012
Copyright 1992 by the American Geophysical Union.
Journal of Geophysical Research: Planets (1991–2012)
Volume 97, Issue E8, pages 13643–13665, 25 August 1992
How to Cite
1992), Fluid outflows from Venus impact craters: Analysis from Magellan data, J. Geophys. Res., 97(E8), 13643–13665, doi:10.1029/92JE00981., and (
- Issue published online: 21 SEP 2012
- Article first published online: 21 SEP 2012
- Manuscript Accepted: 28 APR 1992
- Manuscript Received: 1 OCT 1991
Many impact craters on Venus have unusual outflow features originating in or under the continuous ejecta blankets and continuing downhill into the surrounding terrain. These features clearly resulted from flow of low-viscosity fluids, but the identity of those fluids is not clear. In particular, it should not be assumed a priori that the fluid is an impact melt. A number of candidate processes by which impact events might generate the observed features are considered, and predictions are made concerning the rheological character of flows produced by each mechanism. A sample of outflows was analyzed using Magellan images and a model of unconstrained Bingham plastic flow on inclined planes, leading to estimates of viscosity and yield strength for the flow materials. It is argued that at least two different mechanisms have produced outflows on Venus: an erosive, channel-forming process and a depositional process. The erosive fluid is probably an impact melt, but the depositional fluid may consist of fluidized solid debris, vaporized material, and/or melt.