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地震震源分布强烈依赖于构造环境的温度和压力条件。震源机制可使大陆地壳脆性-韧性转换带(下部稳定性过渡边界)的温压条件复杂化。该过渡边界伴随速度弱化作用(有震活动)向速度强化作用(无震活动)的转化。在岩石圈流变和壳幔动力学的基础上研究了与板块边界有关的地震活动,包括板缘地震和俯冲板片地震。俯冲带板缘地震的深度分布受约于脆性摩擦动力机制,而摩擦剪切机制不能满意地解释深震活动,包括俯冲板片地震。这是因为深震震源机制可能与高压、高温条件下的固一固相变有关,而用脆性破裂或摩擦作用来解释就不近合理。以理论与实验研究为依据,本文对与震源物理和震源分布有关的岩石圈流变特性进行了较为深入的论述。
The distribution of earthquakes strongly depends on the tectonic setting of temperature and pressure conditions. Focal mechanisms can complicate temperature and pressure conditions in the continental crust-ductile-to-ductile transition zone (lower stability transition boundary). This transitional boundary is accompanied by a shift in velocity-weakening (seismicity) to a velocity-enhancing (seismic-free) transformation. Based on the lithospheric rheology and crust-mantle dynamics, seismic activities related to plate boundaries are studied, including plate edge and subducting slab seismic. The depth distribution of the edge of the slab edge is controlled by the mechanism of brittle friction, but the friction shear mechanism can not explain the deep seismic activity satisfactorily, including the subducting slab earthquake. This is because the focal mechanism of deep earth may be related to the solid-solid phase transformation under high pressure and high temperature, but it is not reasonable to explain it with brittle fracture or friction. Based on the theoretical and experimental studies, the rheological properties of lithosphere related to source physics and source distribution are discussed in detail.