East—West Structures in the Sanjiang Region, Western Yunnan and Their Implications
East—West Structures in the Sanjiang Region, Western Yunnan and Their Implications
复制标题
DOI：
--
复制
发表时间：
2004
期刊：
影响因子：
--
通讯作者：
G. Ye
中科院分区：
文献类型：
--
作者：
G. Ye
地球物理场分析表明，三江造山带存在多个近东西向构造。这些东西向的构造埋藏深，在布格重力异常图上表现出长波长、低振幅的特征。它们在地质图上表现为一系列近东西向的断裂、岩体和矿床，在遥感图像上表现为若干浅埋平行构造带。根据地质、地球物理和地震速度资料，认为这些东西向构造可能是青藏高原碰撞或挤压后，深部物质从块体中向东南方向挤出的流变构造。也可能是三江造山带在挤压碰撞和走滑背景下，伸展构造或老构造重新活化的结果。它们可能与青藏高原南部的南北向伸展构造（裂谷）具有相同的形成机制。
An analysis of the geophysical field shows that there are several nearly east—west structures in the Sanjiang (i.e. three rivers: the Jinsha, Nujiang and Lancang rivers) orogenic zone. These east—west structures are buried and deep lying, showing characteristics of the long wave-length and low amplitude in the Bouguer gravity anomaly map. They are reflected as a series of nearly east—west faults, plutons and ore deposits on the geological map, and as a number of shallow-buried parallel structure zones on the remote sensing images. Based on data of geology, geophysics and seismic velocity, it is suggested that these east—west structures may be the rheomorphic structures of deep materials squeezed out southeastward from the blocks after the collision orogeny of the Qinghai—Tibet Plateau. Or they may have resulted from the re-activation of the extensional or old structures in the compression—collision and strike-slip settings of the Sanjiang orogenic zone. They may have the same formation mechanism as the north—south extensional structures (rifts) in the southern Qinghai—Tibet Plateau.