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介绍并讨论了现代地震学时期发生的最大大陆板内地震的1000多次余震的空间分布。其数据是由8台便携式数字测震仪组成的台网在主震后17天开始用3周时间记录的。我们已计算了高质量的单一事件位置,所基于的是由这个地区震级为2-5 的地震确定的一维速度模型。余震定位揭示出活动集中在一个近东走向的向南倾斜的面上,呈梯形分布。活动带沿走向逐渐变短,从深度约为5 km的浅部长度约为45 km到 35 km的深度不足25 km。整个破裂区面积约为1300 km2。我们估计主震的静态应力降为16±2 MPa。余震扩展到几乎整个地壳,集中在10 km深的上地壳,和约26 km 深的下地克。断层破裂没有在地表出露,也不知道它在2001地震前是否是活断层。余震数据与布季主震一致,主震是由夭折裂谷的拉张作用形成的断层在收缩过程中的重新激活引起的。
The spatial distribution of more than 1000 aftershocks in the largest continental intraplate earthquake that occurred in the modern seismology period was introduced and discussed. The data is recorded by a network of eight portable digital seismometers starting at 17 days after the main shock for three weeks. We have calculated the location of a single, high-quality event based on a one-dimensional velocity model determined by an earthquake of magnitude 2-5 in this area. The aftershock positioning reveals that the activity is concentrated on a south-inclined surface near the eastward direction and is trapezoidally distributed. The active zone becomes progressively shorter along the strike, with a depth of less than 25 km from a shallow part of about 5 km at a depth of about 45 km to 35 km. The entire rupture area is about 1300 km2. We estimate that the static stress drop of the main shock is 16 ± 2 MPa. The aftershocks extended to almost the entire crust, centered on the upper crust to 10 km deep, and the Lower Dick about 26 km deep. Fault rupture is not revealed on the surface and it is unknown if it was an active fault before the 2001 earthquake. The aftershock data is consistent with the Buji mainshock, which is caused by the reactivation of the fault formed by the extension of the abrupt rift.