Tectonics of Cerberus Fossae unveiled by marsquakes

The InSight mission has measured Mars' seismicity since February 2018 and allowed to investigate tectonics on another planet. Seismic data shows that most of the widely distributed surface faults are not seismically active, is mostly originating from a single graben structure, Cerberus Fossae. We show both major families marsquakes characterized by low high frequency content, LF HF events respectively, located central eastern parts this system. hypocenters at 15-50 km depth spectral character suggests structurally weak, potentially warm source region consistent with recent volcanic activity those depths. occur in brittle, shallow part crust might originate fault planes associated flanks. Estimated magnitudes between 2.8 3.8, resulting total seismic moment release within Fossae 1.4-5.6 $\times10^{15}$ Nm/yr, or least half observed value entire Our findings confirm represents unique tectonic setting shaped current day processes, implications for minimum local heat flow.