Ductile normal Faults

- Normal ductile faults at Cap Creus -

The most common late ductile shear zones are predominantly dextral (and rarely sinistral). They are oriented NE-SW and clearly visible on the map below. Other shears of smaller amplitude display vertical displacements.They can be seen, for example, at the northern end of the Cape Peninsula (red box on the map and satellite image from Goggle Maps).

Map of Cap Creus after J. Carreiras

Let's focus on the block identified on the satellite image below. The 2 arrows indicate the viewpoints of the following photos..

Northern end of the Cape Peninsula. Image "goggle maps"

The following two photos are taken from the direction indicated by the arrow on the right.

This block slides towards the sea along fracture planes

The block is cut by fractures dipping towards the sea. These are well marked by steps leaning towards the sea. These are the previously described fractures that drive the ductile shear zones of Cala Fredosa.

In its upper part, the block slides along a ductile shear located on a fracture

The curvature of the schistosity shows that the block collapsed towards the sea: it is therefore a normal ductile fault.

While climbing on the western side of the block (left arrow on the satellite image), the observation of the curvature of the schistosity is evident:

Are these ductile normal faults deep evidences of the post-orogenic collapse of the Hercynian chain in the Pyrenees?