【摘要】 本文研究了滇西北伸展构造区活动构造、地震活动和新构造环境的特点。该区构造与地震的活动强度为南、北部强,中间弱;第四纪最大沉降中心、湖积台地及第四纪褶皱分布呈对角对称。滇西北地区的伸展构造是在近南北向挤压力和南西—北东向剪切力的共同作用下形成的,其合力方向为北北东,与用水压致裂法和物理模拟获得的结果相符。该区在形成机制上属于一种特殊的拉分构造。更多还原

【Abstract】 The paper discusses the characteristics of active tectonics, seismicity and neo-tectonics environment of Northwest Yunnan extenional region. The active intensity of both tectonics and seismicity is strong in the areas near the south and north boundaries, but weak in the middle. The distribution of the most-subsided areas, lacustrine terrace and Quanternary fold is characterised by the diagonal symmetry. Formation of extensional region in Northwest Yunnan can be illustrated by passive model, experiencing the action of both compresional force in the N-S direction and shear force in the SW-NE direction and belonging to a special pull-apart tectonics. The direction of the synthetic force is NNE, which is coincided with the results acquired by the methods of water-compressed rupture and physical model.更多还原