Extended rift-associated volcanism in Ganis Chasma, Venus detected from
Magellan radar emissivity
Jeremy Brossier
Institute for Space Astrophysics and Planetology IAPS, National Institute of Astrophysics, 100 Via del Fosso del Cavaliere, 00133 Rome, Italy, Institute for Space Astrophysics and Planetology IAPS, National Institute of Astrophysics, 100 Via del Fosso del Cavaliere, 00133 Rome, Italy, Institute for Space Astrophysics and Planetology IAPS, National Institute of Astrophysics, 100 Via del Fosso del Cavaliere, 00133 Rome, Italy, Institute for Space Astrophysics and Planetology IAPS, National Institute of Astrophysics, 100 Via del Fosso del Cavaliere, 00133 Rome, Italy
Corresponding Author:[email protected]
Author ProfileMartha S. Gilmore
Wesleyan University, Department of Earth and Environmental Sciences, Planetary Sciences Group, 265 Church Street, Middletown, CT 06459, USA, Wesleyan University, Department of Earth and Environmental Sciences, Planetary Sciences Group, 265 Church Street, Middletown, CT 06459, USA, Wesleyan University, Department of Earth and Environmental Sciences, Planetary Sciences Group, 265 Church Street, Middletown, CT 06459, USA, Wesleyan University, Department of Earth and Environmental Sciences, Planetary Sciences Group, 265 Church Street, Middletown, CT 06459, USA
Author ProfileAbstract
Exploration of Venus in the 1970–1990’s revealed that the geology of
Venus, the most Earth-like of the terrestrial planets, was decidedly
un-Earth-like, with no plate tectonics, and no record of the first 80%
of its history. A major outstanding question is whether Venus is still
volcanically active today. We find that regions of Ganis Chasma have low
radar emissivity values, due to low volumes of high dielectric minerals
formed by surface – atmosphere weathering on the timescales of around
10s Ma. This confirms the presence of geologically recent volcanism in
association with this major tectonic rift zone. The spatial
correspondence of this emissivity signature with transient thermal
anomalies suggests that Venus has been volcanically active at this site
for at least the last few decades, a prediction that can be tested with
space missions to Venus in the coming decade.
