Geologic evidence of hotspot activity on Venus: Predictions for Magellan

Abstract

A number of distinctive types of geologic features have been identified on Venus that are interpreted to be related to thermal plumes including domal rises, coronae and major composite shield volcanoes. We document the basic characteristics of these features as well as their distribution. The three types of features have related morphologies, and we interpret them to represent a continuum of features formed by mantle plumes at scales from 100's to over 1000 km. The Artemis structure, located in Aphrodite Terra, is proposed to be a large corona. If crustal spreading processes are operating on Venus, hotspot features should form chains on the surface as seen in terrestrial ocean basins. On the basis of current data on hotspot‐related feature distribution on Venus, no clear evidence exists for hotspot chains. The complete distribution of hotspot features in Magellan data will be used to understand better the relationship between interior processes and surface features, as well as to provide a test for the crustal spreading hypothesis.