The fossae have long been proposed to be very tectonically active. Our goal is to look for new rockfalls that might indicate current seismic shaking.
A note: Mars does not have tectonic plates, but the activity is mostly due to the pressure of the material that can cause a shifting of the terrain.

Image is less than 5 km (3 mi) across and is 277 km (172 mi) above the surface. For full images including scale bars, visit the source link.

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NASA/JPL-Caltech/UArizona