A
fold and thrust belt is a series of mountainous foothills adjacent to an
orogenic belt, which forms due to contractional
tectonics. Fold and thrust belts commonly form in the
forelands adjacent to major orogens as deformation propagates outwards. Fold and thrust belts usually comprise both
folds and
thrust faults, commonly interrelated. They are commonly also known as thrust-and-fold belts, or simply thrust-fold belts.