Recent hotspot volcanism on Venus from VIRTIS emissivity data.
Smrekar, Suzanne E ; Stofan, Ellen R ; Mueller, Nils ; et al. ; - ASI Sponsor
Apr - 2010
ISSN : 1095-9203 ;
journal : Science (New York, N.Y.)

Issue : 5978
type: Article Journal

Abstract
The questions of whether Venus is geologically active and how the planet has resurfaced over the past billion years have major implications for interior dynamics and climate change. Nine hotspots--areas analogous to Hawaii, with volcanism, broad topographic rises, and large positive gravity anomalies suggesting mantle plumes at depth--have been identified as possibly active. This study used variations in the thermal emissivity of the surface observed by the Visible and Infrared Thermal Imaging Spectrometer on the European Space Agencys Venus Express spacecraft to identify compositional differences in lava flows at three hotspots. The anomalies are interpreted as a lack of surface weathering. We estimate the flows to be younger than 2.5 million years and probably much younger, about 250,000 years or less, indicating that Venus is actively resurfacing.

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