岩心差应变分析法是汶川地震断层科学钻探(WFSD)项目地应力测量的主要手段之一,该技术通过高压容器对取之于钻孔不同深度的实验样品施加围压,观察先前由于失去地层应力而膨胀产生的裂纹重新闭合,并通过裂纹闭合过程差应变曲线分析,确定主应力大小和方向.WFSD-1孔12个岩心样品的DSA测试结果表明:断层上下盘的应力状态有明显差异,区域地应力不仅随深度增加,还与地质结构和岩石的物理性质等因素有关.%The Nanping Basin, located between the India and Eurasian plates, was a large Mesozoic-Cenozoic basin and deposited huge thick continuous Cretaceous strata, which recorded well the regional tectonic movement characteristics. Based on field survey and indoor data sorting, a technique of balanced section across the Lanping-Jinding region was applied to a NW-SN geological profile to reconstruct the crust shortening history from Cretaceous and to understand the nature of the basin and to check up its geological structure explained correctly and to make a digital analysis. The results showed that the total length about the Cretaceous crust shortening was 2. 938 km from the under section of Jingxing Formation to Nanxin Formation, and Nanxin Formation had the most strongest tectonic movement.
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