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The lithospheric structures beneath the Pyrenees, which holds the key to settle long‐standing controversies regarding the opening of the Bay of Biscay and the formation of the Pyrenees, are still poorly known. The temporary PYROPE and IBERARRAY experiments have recently filled a strong deficit of seismological stations in this part of western Europe, offering a new and unique opportunity to image crustal and mantle structures with unprecedented resolution. Here we report the results of the first tomographic study of the Pyrenees relying on this rich data set. The important aspects of our tomographic study are the precision of both absolute and relative traveltime measurements obtained by a nonlinear simulated annealing waveform fit and the detailed crustal model that has been constructed to compute accurate crustal corrections. Beneath the Massif Central, the most prominent feature is a widespread slow anomaly that reflects a strong thermal anomaly resulting from the thinning of the lithosphere and upwelling of the asthenosphere. Our tomographic images clearly exclude scenarios involving subduction of oceanic lithosphere beneath the Pyrenees. In contrast, they reveal the segmentation of lithospheric structures, mainly by two major lithospheric faults, the Toulouse fault in the central Pyrenees and the Pamplona fault in the western Pyrenees. These inherited Hercynian faults were reactivated during the Cretaceous rifting of the Aquitaine and Iberian margins and during the Cenozoic Alpine convergence. Therefore, the Pyrenees can be seen as resulting from the tectonic inversion of a segmented continental rift that was buried by subduction beneath the European plate. New tomographic images of the Pyrenees and Massif CentralThe deep Pyrenean architecture is segmented by NE‐SW transfer zones

Since February 2019, NASA's InSight lander is recording seismic signals on the planet Mars, which, for the first time, allows to observe ongoing tectonic processes with geophysical methods. A number of Marsquakes have been located in the Cerberus Fossae graben system in Elysium Planitia and further west, in the Orcus Patera depression. We present a first study of the focal mechanisms of three well‐recorded events (S0173a, S0183a, S0235b) to determine the processes dominating in the source region. We infer for all three events a predominantly extensional setting. Our method is adapted to the case of a single, multicomponent receiver and based on fitting waveforms of Pand Swaves against synthetic seismograms computed for the initial crustal velocity model derived by the InSight team. We explore the uncertainty due to the single‐station limitation and find that even data recorded by one station constrains the mechanisms (reasonably) well. For the events in the Cerberus Fossae region (S0173a, S0235b) normal faulting with a relatively steep dipping fault plane is inferred, suggesting an extensional regime mainly oriented E‐W to NE‐SW. The fault regime in the Orcus Patera region is not determined uniquely because only the Pwave can be used for the source inversion. However, we find that the Pand weak Swaves of the S0183a event show similar polarities to the event S0173, which indicates similar fault regimes. As time passes, the mysterious interior of Mars is slowly being unraveled due to the detection and analysis of Marsquakes recorded with a seismograph carried by the InSight lander. Close to 400 Marsquakes have so far been identified, yet only a handful of those show similarities to earthquakes. Those earth‐like events are located near the Cerberus Fossae and Orcus Patera regions. We take advantage of the similarity between Marsquakes and earthquakes and apply a methodology developed for earthquake characterization before seismic recorders became abundant on Earth. We find that the Marsquakes in these source regions are dominated by extensional rather than compressing features. This is important information to further understand what causes Marsquakes. We infer the tectonic setting in Cerberus Fossae on Mars by seismic source inversionWe present a robust inversion strategy for single‐station moment tensor inversionThree Marsquakes recorded by InSight reveal a predominantly normal faulting regime We infer the tectonic setting in Cerberus Fossae on Mars by seismic source inversion We present a robust inversion strategy for single‐station moment tensor inversion Three Marsquakes recorded by InSight reveal a predominantly normal faulting regime