Arresting mechanism of earthquake faulting

地震断层的阻止机制

• 批准号: 08640522
• 负责人: YAMASHITA Teruo
• 金额: $ 0.9万
• 依托单位: University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08640522/
• 关键词: fault; boundary integral equation method; rupture; 亀裂; 相互作用

Geometrical complexity of earthquake faults will be a manifestation of mechanical inhomogeneities of the earth's crust. It will therefore be closely associated with the arresting mechanism of dynamic earthquake faulting. A detailed study was carried out on the relation between the complexity of earthquake faulting and the arresting mechanism of faulting.High-pressure fluids existing in a fault zone can promote an earthquake rupture. The effect of pore-fluids on the earthquake rupture, especially on the arresting of rupture, is also studied in this research project.We developed new numerical methods to simulate an arbitrary-shaped rupture on the basis of boundary integral equation methods (BIEM). One of the difficulties in such a BIEM treatment is the evaluation of hypersingular integrals. We first made a formulation from the regularization approach, and derived a set of non-hypersingular boundary integral equations, both elastodynamic and elastostatic, for the analysis of arbitrarily s … More haped 2-D cracks. We carried out the simulation of dynamic cracks with side-branches. The results of the simulations show that the stress concentration at the propagating tip of the main crack is lowered by the presence of the side-branches. This suggests that the branching of the crack plays an important role in the deceleration and arresting mechanism of earthquake rupturing.The method based on the regularization approach is somewhat complicated, so that we next developed a more efficient method taking finite parts of hypersingular integrals. Numerical simulation of unsteady dynamic propagation of arbitrarily shaped 2-D cracks will be easily carried out using this method.It is well known from field observations that a fault zone is generally regarded as fluid conduit. If an earthquake rupture takes place, non-linear mechanical interactions occur between the fault fluids and the rupture. Our analysis of the interactions showed that the fluids can a factor to arrest the earthquake rupture if there is a high inhomogeneiry in the distribution of the fluid in the fault zone. Less

地震断层的几何复杂性将是地壳机械不均匀性的表现。因此，它将与动态地震断层的逮捕机制密切相关。对地震断层的复杂性与阻碍断层机制之间的关系进行了详细的研究。断层区域中存在的高压液可以促进地震破裂。在该研究项目中还研究了孔流体对地震破裂的影响，尤其是对破裂的捕捉。我们开发了新的数值方法，以基于边界积分方程方法（BIEM）模拟任意形状的破裂。这种BIEM治疗中的困难之一是评估超积分。我们首先从受调节的方法制作了一个公式，并得出了一组非弹性边界积分方程，包括弹性动力学和弹性静态，以分析任意S的分析。我们用侧支线进行了动态裂纹的模拟。模拟的结果表明，主体的存在降低了主裂纹的传播尖端的应力浓度。这表明裂缝的分支在地震破裂的减速和阻止机制中起着重要作用。基于调节方法的方法有些复杂，因此我们接下来开发了一种更有效的方法，将有限的部分用于超级积分。使用这种方法很容易地对任意形状的2D裂纹的不稳定动态传播进行数值模拟。从现场观察结果中众所周知，断层区通常被视为流体导管。如果发生地震破裂，则断层烟与破裂之间发生非线性机械相互作用。我们对相互作用的分析表明，如果在断层区域中流体的分布中，流体可以阻止地震破裂的因素。较少的

项目成果

山下輝夫: "Mechanical effect of fluid migration on the complexity of seismicity" Journal of Geophysical Research. 102. 17797-17806 (1997)

Teruo Yamashita：“流体运移对地震活动复杂性的机械效应”地球物理研究杂志 102。17797-17806 (1997)。

多田 卓: "Non-hypersingular boundary integral equations for two-dimensional non-planar crack analysis" Geophysical Journal International. 130. 269-282 (1997)

Takashi Tada：“二维非平面裂纹分析的非超奇异边界积分方程”《国际地球物理学杂志》130. 269-282 (1997)。

Tada T.: "Non-hypersingular boundary integral equations for two-dimensional non-planar crack analysis" Geophys.J.Int.130. 269-282 (1997)

Tada T.：“二维非平面裂纹分析的非超奇异边界积分方程”Geophys.J.Int.130。

山下 輝夫: "Mechanical effect of fluid migration on the complexity of seismicity" Journal of Geophysical Research. 102. 17797-17806 (1997)

Teruo Yamashita：“流体运移对地震活动复杂性的机械效应”地球物理研究杂志 102。17797-17806 (1997)。

多田卓・山下輝夫: "Non-hypersingular boundary integral equations for two-dimensional non-planar crack analysis" Geophysical Journal International. 130. 269-282 (1997)

Taku Tada 和 Teruo Yamashita：“二维非平面裂纹分析的非超奇异边界积分方程”《国际地球物理学杂志》130. 269-282 (1997)。