Distortion of Continental Asia

Abstract

Asiatic arcs are capable of being divided into several classes according to type and distribution. Those which run along and parallel to the Pacific border form several peri pacific chains, including the festoon islands, with the convex front of each individual arc facing south-east. It is found that these arcs have resulted from modified waves of anticlinoria of Neocathaysian or generally N.N. E. trend due to the interception and repression at regular intervals by powerful E.-W. zones of compression. The second class comprises trans-continental chains of the ε type of arcs arranged on the whole east-west with their main convex front facing south. They are traced right across the Asiatic continent from the Pacific border to the eastern MeditelTanean except in the Himalayan and Kangtien-Burma geosynclines and in the unruly mass of Tibet. These fold-arcs arising from various parts of the abandoned site of the Tethys stand in strong contrast to the shield-like mass of India, where fractures of definite orientation predominate at least since the latter part of the pre-Cambrian era. From the evidence furnished by distorted clay it can be shown by analogy that both the peripacific and trans-continental arcs are due to southward movements of parts of the continental mass. Such movements are in agreement with the requisite cause for setting up horizontal pressure to produce lineaments in Gondwanaland.