Displacement and Geometrical Characteristics of Earthquake Surface Ruptures: Issues and Implications for Seismic-Hazard Analysis and the Process of Earthquake Rupture
Displacement and Geometrical Characteristics of Earthquake Surface Ruptures: Issues and Implications for Seismic-Hazard Analysis and the Process of Earthquake Rupture
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DOI：
10.1785/0120070111
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发表时间：
2008-08
影响因子：
3
通讯作者：
S. Wesnousky
中科院分区：
文献类型：
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作者：
S. Wesnousky
现在有大约36次历史上的地震，研究人员已经绘制了地震破裂轨迹图，并对沿断层走向观察到的同震滑动进行了描述。这里编制的地图和滑动分布是为了在地震危险性分析和断层力学方面确立观测界限。通过分析可以得到初步的统计基础，以预测在已绘制的断层上发生地震时沿走向的地点的破裂终点和地表滑动量。观测结果还支持这样的观点，即在大型横向传播的地震断裂前缘存在一个过程带或大约3-4公里的体积，其中应力变化可能足以触发相邻断层的滑动，并且地震断裂的最终长度主要由断层轨迹的几何复杂性和由于过去地震的位置而产生的沿断层累积应力水平的变化控制。除此之外，还可以补充观察到，地震地表滑动分布的形式用不对称曲线形式比用对称曲线形式更好地描述，而且地震震中似乎与沿走向观测到的最大地表滑动区域没有任何系统的联系。在线资料：地表破裂图，地表滑动分布的数字化值和曲线拟合，以及表1和表2的注释和参考资料。
There now exist about three dozen historical earthquakes for which in- vestigators have constructed maps of earthquake rupture traces accompanied by de- scriptions of the coseismic slip observed along the fault strike. The maps and slip distributions are compiled here to place observational bounds on aspects of seismic- hazard analysis and fault mechanics. Analysis leads to an initial statistical basis to predict the end points of rupture and the amount of surface slip expected at sites along the strike during earthquakes on mapped faults. The observations also give support to the ideas that there exists a process zone or volume of about 3-4 km in dimension at the fronts of large laterally propagating earthquake ruptures within which stress changes may be sufficient to trigger slip on adjacent faults, and that the ultimate length of earthquake ruptures is controlled primarily by the geometrical complexity of fault traces and variations in accumulated stress levels along faults that arise due to the location of past earthquakes. To this may be added the observation that the form of earthquake surface-slip distributions is better described by asymmetric rather than symmetric curve forms and that earthquake epicenters do not appear to correlate in any systematic manner to regions of maximum surface slip observed along strike. Online Material: Maps of surface ruptures, digitized values and curve fits to surface-slip distributions, and notes and references for Tables 1 and 2.