Ries impact structure (Germany); Azuara and Rubielos de la Cérida impact structures (Spain): peculiar structural setting

 B (close-up)

Peculiar structural setting in autochthonous Jurassic limestones at the eastern rim of the Ries impact structure (Wemding; formerly Schneider quarry). Photos: July, 2001.
Interpretation: The strange abrupt change from horizontal layering to steeply dipping and strongly deformed limestone beds has resulted from horizontal thrust under very high overburden pressure in the excavation and ejection process.Similar strange deformations can be observed at the rims of the Azuara and Rubielos de la Cérida impact structures (Spain):
Aguilón; Jurassic limestones (Azuara structure). Note the bedding in the base speaking against a tectonic fault.
near Santa Eulalia; Muschelkalk limestones (Rubielos de la Cérida structure). Note the block of bedded limestone floating in the highly brecciated material.
In all three cases, a tectonic interpretation of the layering offers considerable difficulties.