累积损伤疲劳断裂——地壳构造变形的一种基本机制  

FATIGUE FRACTURE UNDER THE CUMULATIVE DAMAGE--ONE OF THE BASIC MECHANISMS FOR STRUCTURAL DEFORMATION OF THE CRUST

作　　者：吴海威[1] 

机构地区：[1]中国科学院地质研究所

出　　处：《地质科学》1991年第2期101-110,T001,共11页Chinese Journal of Geology(Scientia Geologica Sinica)

摘　　要：潮汐应力引起地壳岩石的循环应变、累积疲劳损伤,形成疲劳断裂。本文给出疲劳断裂野外宏观地质特征,并对显微构造、小构造、大陆与大洋区域构造、第四纪软岩层中的疲劳断裂实例进行了分析,指出部分石英变形纹就是疲劳纹,以及环太平洋地震带、海底磁异常条带和潮汐作用、疲劳断裂机制的相关性;给出累积损伤—微体积的玄武岩浆上侵—沿疲劳断裂上涌—海底扩张的模式;推测大陆与海洋地壳的疲劳寿命。The tidal stress gives rise to cyclic strain, and then forms cumulative damages and fatigue fractures in crustal rocks. Three macroscopic geological characteristies of fatigue fracture are given in this paper. Many fatigue fractures, for example, the micro-structures, continental and oceanic tectonic systems, and structural joints in Quaternary soft deposits are analysed. The deformation lamellae in quartz may be fatigue micro-cracks. There also exists the relationship between the fatigue mechanism and the circum-Pacific seismic zone, or the sea floor magnetic anomaly patterns and tidal effect. A new model, cumulative damage-micro-body basalt intrusion along fatigue cracks-upper mantle upwelling along fatigue faults-ocean floor spreading, is shown. The fatigue-lifes of continental and oceanic crusts are suggested.

关 键 词：地壳构造 变形 疲劳断裂 累积损伤 

分 类 号：P313.2[天文地球—固体地球物理学]