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壳内多震层的介质结构及其内、外环境是制约地震（尤其强震）在该层内孕育、发生的重要因素。现今多震层孕震环境研究所取得的主要进展如下：多震层位于上地壳下部至中地壳，岩石组合为角闪岩相（上部为绿片岩相）变质岩和花岗质岩石；多震层具有相对高速、高密度、高阻的介质结构，其下部对应脆韧变形转换带和最大剪切应力带；多震层（或强震震源）之下存在壳内低速高导体；多震层应力场具有区域性分区特点，壳内地震活动截止温度约３００～４００℃；多震层内震源断层具有区域性特点，不同地区震源断层可能具有不同的孕震机制；“坚固体孕震模式”对地震预报具有一定的指导作用。
The dielectric structure of the multi-seismic shell in the crust and its internal and external environments are important factors that restrict the occurrence of earthquakes (especially strong earthquakes) in this layer. The main progresses made by the research on the seismogenic environment of the present multi-seismogenic zone are as follows: the multi-seismic zone is located in the lower part of the upper crust to the middle crust, and the rock assemblages are amphibolite facies (upper greenschist facies) metamorphic rocks and granitic rocks; Layer has a relatively high-speed, high-density, high-resistivity dielectric structure, the lower part of which corresponds to the brittle-ductile deformation transformation zone and the maximum shear stress zone; the low-speed and high-conductor in the shell exist below the multi-seismic layer The seismic stress field has regional zoning characteristics. The cut-off temperature of seismic activity in the crust is about 300-400 ℃. The focal faults in the multi-seismic zone have regional characteristics, and the source faults in different areas may have different seismogenic mechanisms. Mode "has a guiding role in earthquake prediction.