The Pontarlier Tear Fault system is one, if not the major tear fault in the Jura Mountains. This N-S oriented sinistral tear fault crosscutd all of the folded and thrusted Main Range of the Jura fold-and-thrust belt and extends to the South into the Molasse Basin. The fault systems is restricted to the detached Mesozoic sedimentary cover and is conjugated to the East with NW_SE oriented dextral tear faults such as the Mormont-La Sarraz Fault.