中卫—同心活动断裂带现代构造应力分布特征及地震破裂危险区判定

采用弹性模型对中卫—同心活动断裂带在区域现代构造应力场作用下的应力分布特征进行数值模拟,并在此基础上应用岩石破裂危险度KR及断层滑动危险系数KF两个判别指标对该断裂带未来地震破裂危险区进行判定。结果显示该活动断裂带上的应力分布具有明显的分段性,大致以红谷梁和同心为界分为三个区段。地震破裂危险区段主要位于红观观至红谷梁东区段,在地震发生时起始破裂区位于中卫南—碱沟,破裂向两侧扩展,向东很快衰减,而向西破裂扩展范围较大,可达红观观。

Characteristics of Present Tectonic Stress along Zhongwei-Tongxin Active Fault Zone and Predication of Earthquake Rupture Risk Area

The characteristics of present tectonic stress along Zhongwei-Tongxin fault zone are obtained by using the finite-element simulation with an elastic model,and the future earthquake rupture risk areas are predicated using rock rupture risk coefficient(KR) and fault gliding risk coefficient(KF) as criteria in this article.The result shows that the modern stress along the fault zone has a feature of segmentation and can be divided into three segments.The earthquake rupture risk areas is from Hongguanguan to Hongguliang.When earthquake occur,the initial rupture area will locate from south Zhongwei to Jiangou,and quickly expands to two sides.Toward east the rupture stops quickly and toward west it attenuates slowly until it reaches Hongguanguan.