Abstract: Based on the study of the genetic features of mineral associations and metamorphic facies in Miyun metamorphic rocks,the characters of repeated-seismic layers have been proposed in this paper.It is suggested that the differential deformation has a close relation to the generation of strong seisms.Taking the principal elements of flow cleavage and fracture cleavage as well as their dynamic implications into account,a generation process of strong earthquakes has been proposed: the mechanism of differential deformation causes an initiation of strong earthquakes.Briefly speaking,distinct rock types in a dynamically forced system are deformed asynchronously,so there should be a mutually-restricted force in the system.When the increase of the force has attained the critical limit,the initial steady state of the system is not maintained,leading to a change of the distance in the relating moment of force.During this process,the potential energy is transformed into kinetic energy,forming a shear-compressive thrust that will cause an initiation of strong earthquakes.Therefore,the force of differential deformation is a driving force of strong-seismic event.This mechanism is proposed in a qualitative consideration without any scale restriction.It is also considered that the equilibrium of distinct energies has been involved in this process.Based on the proposed mechanism,the relationship between slow deformation and quick earthquake generation,seismostructures and petrology have been demonstrated in this paper as well.

摘要： 从密云变质岩的矿物组合和变质相律中,本文揭示出多震层的某些主要特征。在地壳10—25公里深处的不同物性、成分的岩石,彼此具有不同程度的形变。差异形变的机理是按应变椭球体的形成过程来解释的。其中,不同岩石相对的流劈理和破劈理是在同一受力系统下发育形成。当达到差异形变的极限状态时,破劈理可导致产生压剪逆掩断层,激发强震,故差异形变力即是激发强震的驱动力。本文并对缓慢形变和快速发震、震源体构造和岩石作了某些初步探讨。