Author: PETER J. SMITH
Department of Earth Sciences
Milton Keynes, U.K.
- The Cleopatra structure on Venus, 100 kilometers in diameter, has the morphology of an impact crater but the distinctly different depth-diameter ratio of a volcanic crater. It is not yet possible to decide whether it is a very strange impact crater or a very strange volcanic crater.
A.T. Basilevsky, B.A. Ivanov, "Cleopatra crater on Venus: Venera 15/16 data and impact/volcanic origin controversy," Geophysical Research Letters, 17
- Based on the mapping of radar images and the analysis of geologic units and topography, the Freyja Montes deformation zone of Venus has been interpreted as a site of large-scale crustal convergence and imbrication (owing to the underthrusting of the North Polar Plains beneath Ishtar Terra) that have resulted in crustal thickening and uplift. Moreover, these processes appear to be continuing today. The implication is that large-scale tectonic activity was,...