This Magellan view of Ovda Regio shows a corona, a large volcanic and tectonic structure common on Venus. Coronae are characterized by radial and concentric scarps and ridges and by small volcanos and lava flows. The relatively smooth center of this corona measures 80 kilometers across and is about 3 kilometers lower in elevation than the surrounding ridges. Several episodes of deformation are apparent in this corona. Many of the concentric fractures and graben formed first, and then were faulted by the prominent radial fault system. Several irregular volcanic pits are visible on the flanks of this structure. Coronae may form when a region is uplifted and then collapses downward. One possible interpretation is that these features are collapsed volcanic structures, probably related to upwelling of material from deep in the mantle. Magellan
image F-MIDR 00N076. Right click here to download a high-resolution version of the image (989 KB)
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