Seismo-acoustic coupling efficiency at the surface of Venus

Abstract

The extreme conditions at the surface of Venus pose a challenge for monitoring the planet’s seismic activity using long-duration landed probes. One alternative is using balloon-based sensors to detect venusquakes from the atmosphere. This presentation assesses the efficiency of seismic-to-acoustic energy transfer from Venus' crust to its deep atmosphere. It is, therefore, restricted to immediate neighborhood of the planet's surface. In order to account for supercritical conditions near the surface, the Peng-Robinsonequation of state is used to obtain the acoustic wavenumber in the lower atmosphere. The energy transported across the surface from deep and shallow sources is two orders of magnitude larger than on Earth, pointing to a very strong seismo-acoustic coupling. For a more realistic scenario, we simulated the acoustic field generated in the lower atmosphere by the ground motion arising from a vertical array of subsurface point-force sources. The resulting transmission loss maps show a strong epicentral cone accompanied by contributions from leaky surface waves.