高亚洲区内一种新类型的断层——垂直转换断层及其地球动力学意义

VERTICAL TRANSFORM FAULT A NEW TYPE OF FAULT IN HIGH ASIA AND ITS SIGNIFICANCE FOR GEODYNAMICS

自６０年代以来，国际上进行了许多大地地球物理研究，包括重力、地震测深和热流等，对高亚洲下部地壳和地幔的结构揭示出许多新现象。特别应该指出的是，在高亚洲，包括帕米尔—喜马拉雅地区、青藏高原，都反映出一组穿透地壳、错开莫霍面的高角度深断裂。但是，对这组深断裂的分析研究很不足。本文将对这组断裂进行讨论，辨认出它们是一组垂直的转换断层，命名为垂直转换断层（Ｖｅｒｔｉｃａｌｔｒａｎｓｆｏｒｍｆａｕｌｔｓ）。它们在高亚洲隆升和年青造山作用（Ｍｏｕｎｔｉａｎ－ｂｕｉｌｄｉｎｇ）方面具有独特的动力学作用。

Since the sixties ,a lot of geophysical work ,including gravity survey ,seismic sounding and heat flow measurements ,has revealed many new phenomena about the structures of the lower crust and mantle underneath High Asia .Among other things ,it should be pointed out that a set of high angle deep faults penetrating the crust and cutting the Moho have been displayed in High Asia ,including the Pamir Himalaya region and the Qinghai Tibet plateau.The study of this set of deep faults ,however,is rather insufficient.In this paper the set of faults are dicussed and recognized as a set of vertical transform faults and so named .They have played a special dynamic role in the uplift and young orogeny of High Asia.The type of fault also should have its position and role in the ancient mountain belt.