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A migratory mantle plume on Venus: Implications for Earth?

Mary G. Chapman·Randolph L. Kirk
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Abstract

A spatially fixed or at least internally rigid hotspot reference frame has been assumed for determining relative plate motions on Earth. Recent 1:5,000,000 scale mapping of Venus, a planet without terrestrial-style plate tectonics and ocean cover, reveals a systematic age and dimensional progression of corona-like arachnoids occurring in an uncinate chain. The nonrandom associations between arachnoids indicate they likely formed from a deep-seated mantle plume in a manner similar to terrestrial hotspot features. However, absence of expected convergent "plate" margin deformation suggests that the arachnoids are the surface expression of a migratory mantle plume beneath a stationary surface. If mantle plumes are not stationary on Venus, what if any are the implications for Earth?

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Journal of Geophysical Research B: Solid EarthArticle

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Mary G. Chapman, Randolph L. Kirk. 1996-07-10. A migratory mantle plume on Venus: Implications for Earth?. https://doi.org/10.1029/96jb00883

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