Three zones, each with a different structural style, have been recognized in the altiplano of the Andes in southern Peru. The western and eastern zones are characterized by folds, the central zone by the chaotic juxtaposition of blocks up to 500 m long (Titicaca melange). Previous authors supposed that the chaotic structure had been caused by folding and overthrusting, but more probably the chaos is the result of subaerial sliding. The melange is thus not of tectonic, but of sedimentary origin, and is hence an olistostrome. Large olistostromes, such as the Titicaca melange, indicate sedimentary-tectonic mass transport and are transitional between structures formed by gravity tectonics (tectonic mass transport) and clastic sediments (sedimentary mass transport). The close ssociation of folds, a large olistostrome, and a thick pile of clastic sediments suggests that all three processes have been important in the area near Lago (Lake) Titicaca.

The great similarity between the Titicaca olistostrome and the Amargosa chaos in Death Valley, California, supports the landslide explanation of this chaos.