在中国地应力分布规律统计分析基础上,通过收集200条青藏地区地壳浅层地应力实测结果,首次统计得到我国青藏地区平均水平地应力与垂直地应力的比值随深度变化的分布曲线,并建立了回归方程。进而分析青藏地区地应力分布规律与特点,发现青藏地区地应力具有总体上符合全国地应力规律,其区域地应力受挤压构造作用显著的特点,尤其是岩浆岩中构造应力显著。研究结果对青藏地区地应力的规律性研究具有重要参考价值,对青藏地区地下工程项目勘察设计、结构分析和工程建设具有重要的实用价值。
Abstract: The distribution curve of the Ratios of the Average Horizontal Geostress and the Vertical Geostresses (RAHVG) varying with depth and regression equation were obtained in Qinghai-Tibet area of China for the first time by collecting and analyzing 200 in-situ measured geostress results based on the analysis of distribution rule of geostress in China. Then the geostress distribution rule and the characteristics were analyzed, and it is found that the geostress in Qinghai-Tibet area conforms to the geostress distribution rule in China, but the geostress in Qinghai- Tibet area is significantly subjected to tectonic squeezing and the tectonic geostress is very obvious in magmatic rock. The RAHVG of the magmatic rock varying with depth in Qinghai-Tibet area is significantly greater than that in China between the depth of 100 m and 800 m. It shows that the stress of the magmatic rock in Qinghai-Tibet area is significantly subjected to squeezing tectonic. The RAHVG of the sedimentary rock varying with depth in Qinghai- Tibet area is basically consistent with that in China, but the value in Qinghai-Tibet area is greater. It shows that thestress of the sedimentary rock in Qinghai-Tibet area is not significantly subjected to squeezing tectonic. The RAH- VG of the metamorphic rock varying with depth in Qinghai-Tibet area is significantly greater than that in China. It shows that the stress of the metamorphic rock in Qinghai-Tibet area is subjected to squeezing tectonic in some de- gree. This study can provide references to the study of distribution characteristics of geostress in Qinghai-Tibet are- a. It also has important practical value for underground engineering survey, design, structural analysis and con- struction in Qinghai-Tibet area.