In the structural geology of major collisional mountain belts like the Himalayas, what is the term given to a low-angle thrust fault that transports huge sheets of older crystalline rocks over younger sedimentary sequences for tens of kilometers?

💡 Solution & Explanation

A nappe is a large structural sheet or overthrust of rock that has been moved considerable distances above a low-angle fault plane during major continental collision events. Strike-slip faults involve horizontal displacement, normal faults form under crustal tension where the hanging wall moves downward, and caldera collapses occur during volcanic eruptions. Recognizing nappe structures helps geologists unravel the complex tectonic stacking of rock formations across the Himalayan orogenic belt.