Pore‐pressure diffusion: A possible triggering mechanism for the earthquake swarms 2000 in Vogtland/NW‐Bohemia, central Europe
Pore‐pressure diffusion: A possible triggering mechanism for the earthquake swarms 2000 in Vogtland/NW‐Bohemia, central Europe
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DOI：
10.1029/2003gl018110
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发表时间：
2003-10
影响因子：
5.2
通讯作者：
M. Parotidis;E. Rothert;Serge A Shapiro
中科院分区：
文献类型：
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作者：
M. Parotidis;E. Rothert;Serge A Shapiro
德国/捷克交界处的Vogtland/NW-Bohemia(VB)具有板内震群反复、第四纪火山活动、断裂系统交叉、上升的岩浆流体与地震活动之间建立联系的特点。由于VB地震活动的触发机制尚不清楚，本研究旨在从孔隙力学的角度探讨流体在VB中的可能作用。我们假设岩浆来源的上升流体通过孔压扩散(即松弛)机制触发地震。水力扩散系数和临界孔压(即导致破坏的临界孔压值)这两个非均匀分布在岩石中的物理场主要控制着这一触发过程。2000年震群资料的分析结果支持这一观点。用一个具有相关扩散系数和临界场的数值模式进一步加强了该模式，该模式成功地模拟了2000年震群的一般时空地震活动图像。
Vogtland/NW‐Bohemia (VB) at the German/Czech border region is characterized by recurring intraplate earthquake swarms, Quaternary volcanism, intersecting fault systems, and an established connection between ascending magmatic fluids and seismicity. As the triggering mechanism of seismicity in VB is still unknown, this study aims to contribute by investigating the possible role of fluids in VB, based on poromechanics. We assume that ascending fluids, of magmatic origin, trigger earthquakes by the mechanism of pore‐pressure diffusion (i.e., relaxation). Two physical fields, the hydraulic diffusivity and the criticality (i.e., critical pore‐pressure value leading to failure), both heterogeneously distributed in rocks, mainly control this triggering process. The results of the analysis of the year 2000 earthquake swarm data support this concept. It is further strengthened by a numerical model, with correlated diffusivity and criticality fields, which successfully simulates the general spatio‐temporal seismicity pattern of the earthquake swarms 2000.