Tectonics of Cerberus Fossae unveiled by marsquakes
Simon C. Stähler, Anna Mittelholz, Clément Perrin, Taichi Kawamura, Doyeon Kim, Martin Knapmeyer, Géraldine Zenhäusern, John Clinton, Domenico Giardini, Philippe Lognonné, W. Bruce Banerdt
The InSight mission has measured Mars’ seismicity since February 2018 and has allowed to investigate tectonics on another planet. Seismic data shows that most of the widely distributed surface faults are not seismically active, and that seismicity is mostly originating from a single graben structure, the Cerberus Fossae. We show that both major families of marsquakes characterized by low and high frequency content, LF and HF events respectively, are located on central and eastern parts of this graben system. LF hypocenters are located at 15-50 km depth and the spectral character suggests a structurally weak, potentially warm source region consistent with recent volcanic activity at those depths. HF marsquakes occur in the brittle, shallow part of the crust and might originate in fault planes associated with the graben flanks. Estimated magnitudes are between 2.8 and 3.8, resulting in a total seismic moment release within Cerberus Fossae of 1.4-5.6 ×1015 Nm/yr, or at least half of the observed value of the entire planet. Our findings confirm that Cerberus Fossae represents a unique tectonic setting shaped by current day volcanic processes, with implications for minimum local heat flow.
Comments: 15 pages, 8 figures, submitted to Nature Astronomy
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Space Physics (physics.space-ph)
MSC classes: 86A15
Report number: InSight contribution 233
Cite as: arXiv:2206.15136 [astro-ph.EP] (or arXiv:2206.15136v1 [astro-ph.EP] for this version)
Submission history
From: Simon Stähler
[v1] Thu, 30 Jun 2022 09:05:07 UTC (9,148 KB)
