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在构造学和地震力学方面,两个重要而又未解决的问题是孕震断层的强度和一次地震的地震矩随破裂面积或破裂长度的变化关系。本文将说明,通常分别处理的这两个问题从根基本上是相关的。按已有的报道,走滑和倾滑地震的地震矩与破裂面积和地震矩与破裂长度关系的数据是离散的,但本文论证了数据实际并不离散,只不过是反映了失稳破坏的断层的强度差异。本文推导出了表达大、小地震之间连续标度的关系式,并证明,断层带的孔隙压力是将走滑型和倾滑型地震联合起来归结为一种作用机制的标度参数。还论证了对于大地震,在大约15km之上断层带孔隙压力在静水压力与接近静岩压力之间连续变化,在此深度之下,有明确的向接近静岩孔隙压力过渡的证据。这些结果对板块构造学、震源物理学,以及从力学上作地震灾害评估均具有重要的意义。
In the area of tectonics and seismic mechanics, two important and unresolved problems are the strength of the seismogenic fault and the variation of the seismic moment with the rupture area or rupture length of an earthquake. This article shows that the two issues that are usually dealt with separately are fundamentally related. According to the existing reports, the data of the relationship between seismic moment and area of rupture and seismic moment and rupture length of the strike-slip and tilt-slip earthquakes are discrete, but this paper proves that the data are not discrete, but reflect the failure The difference in the intensity of faults. In this paper, we deduce the relation between continuous scale of large and small earthquakes and prove that the pore pressure of fault zone is a kind of scale parameter which combines strike-slip and dip-slip earthquakes into a kind of mechanism. It has also been demonstrated that for large earthquakes there is a continuous change in pore pressure across the zone between hydrostatic pressure and near-lithostatic pressure over a distance of about 15 km. Evidence of a near-lithostatic pore pressure transition is evident below this depth. These results are of great significance to plate tectonics, source physics and earthquake mechanics assessment.