Extensional tectonics

[3] Large displacements may juxtapose syntectonic sediments against metamorphic rocks of the mid to lower crust and such structures are called detachment faults.

Large listric regional faults dipping towards the ocean develop with rollover anticlines and related crestal collapse grabens.

Divergent plate boundaries are zones of active extension as the crust newly formed at the mid-ocean ridge system becomes involved in the opening process.

[7] After the collision has finished the zone of thickened crust generally undergoes gravitational collapse, often with the formation of very large extensional faults.

Large-scale Devonian extension, for example, followed immediately after the end of the Caledonian orogeny particularly in East Greenland and western Norway.