Part 5. Plate boundary evolution in the New Guinea region: Helwig?Hall concepts of orogenic mode and underthrusting mode

Abstract

A few years ago, the fact that thick piles of undeformed sediments occur in some trenches, caused several geologists to doubt the reality of subduction. However, in 1971, Oxburgh and Turcotte published the results of a study on the origin of paired metamorphic belts and concluded that in a convergent plate boundary periods of active subduction must episodically alternate with periods of cessation of movements along the subduction zone.