Present‐Day Volcanism on Venus: Evidence from Microwave Radiometry

Abstract

We present new evidence for volcanic eruptions and lava flow emplacement on Venus within the last several decades. An integrated study of a radar‐dark lava flow unit in Bereghinia Planitia on Venus (∼28°E, ∼39°N) based on Magellan data obtained in 1993 reveals a significant apparent microwave thermal emission excess, consistent with increased subsurface temperature due to very recent lava flow emplacement. The flow unit occupies the stratigraphically youngest position in the area and in part is more than 15 years old because it was also observed in the radar map obtained by Pioneer‐Venus in 1978. Analysis of lava flow cooling rates and geological characteristics point to flow material of mafic composition. Future missions can employ this microwave radiometry technique to search for and monitor active volcanism on Venus.

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