Present-day Mars' Seismicity Predicted from 3-D Thermal Evolution Models of Interior Dynamics | INSTITUT DE PHYSIQUE DU GLOBE DE PARIS

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  Present-day Mars' Seismicity Predicted from 3-D Thermal Evolution Models of Interior Dynamics

Type de publication:

Journal Article

Source:

Geophysical Research Letters, Volume 45 (2018)

URL:

http://dx.doi.org/10.1002/2017GL076124

Mots-clés:

InSight, interior dynamics, Mars, modeling, planetology, seismicity, Seismology, THERMAL EVOLUTION

Résumé:

<p>The InSight mission, to be launched in 2018, will perform a comprehensive geophysical investigation of Mars in-situ. The Seismic Experiment for Interior Structure (SEIS) package aims to detect global and regional seismic events and in turn offer constraints on core size, crustal thickness, and core, mantle and crustal composition. In this study, we estimate the present-day amount and distribution of seismicity using 3D numerical thermal evolution models of Mars, taking into account contributions from convective stresses as well as from stresses associated with cooling and planetary contraction. Defining the seismogenic lithosphere by an isotherm and assuming two end-member cases of 573K and the 1073K, we determine the seismogenic lithosphere thickness. Assuming a seismic efficiency between 0.025 and 1, this thickness is used to estimate the total annual seismic moment budget, and our models show values between 5.7 × 10**16 and 3.9 × 10**19 Nm.</p>