摘要
从历史的与整体的观点出发，综合了地质、地貌、地球化学与地球物理的资料，系统地研究了郯庐断裂带各阶段的形态学、运动学以及动力学机制。认为此断裂带开始形成于中、晚三叠世，其长度小于１５００ｋｍ，切割深度小于１５～２０ｋｍ，此时最大左行走滑断距为４３０ｋｍ左右。侏罗纪（２０８～１３５Ｍａ）与中始新世－渐新世（５２～２３．３Ｍａ），此断裂带表现为逆断层活动，断层面受挤压较紧闭。白垩纪－早始新世（１３５～５２Ｍａ），郯庐断裂呈现为略带右行走滑的正断层（走滑断距不超过１００ｋｍ），郯庐断裂带与其北部切割深度约为３０～４０ｋｍ。中新世－更新世（２３．３～０．７３Ｍａ）断裂带表现为带有左行走滑的正断层，走滑断距约５０ｋｍ，断裂带切割深度在５０～８０ｋｍ之间。中更新世（０．７３Ｍａ以来）断裂带又变成略带右行走滑的逆断层，走滑断距不足１００ｍ。由于断裂带形成以来的剥蚀深度不大，地表的断层岩都是碎裂岩与断层泥。沿此断裂带在早白垩世构成了中国东部重要的内生金属成矿带。
In a historical and overall view, combining the geology, geomorphology, geochemistry and geophysics data, the geometry, kinematics and dynamics of the Tancheng-Lujiang fault zone in different stages are studied systematically. It is belivied that the fault zone initiated in the Middle and Late Triassic (230～208 Ma), at that time the length of the fault trace was less than 1500 km, the depth of penetration was about 15～20 km and the maximum sinistral strike-slip was estimated at 430 km. In the Jurassic (208～135 Ma) and Middle Eocene Oligocene (52～23.3 Ma), the faulting acted as a reverse fault. In the Cretaceous-Early Eocene (135～52 Ma), the zone was as a normal faulting with the component of dextral strike-slip (less than 100 km), the length of the fault zone increased considerably to 3 500 km, the depth of Penetration reached up to 30～40 km. The fault zone was as a normal faulting with about 50 km of sinistral displacement, and penetrated into the lithosphere, about 50～80 km in depth in the period of 23. 3～0.73 Ma. Since the Middle Pleistocene (0.73 Ma -), the zone turned to reverse faulting with a slight dextral strike-slip (less than 100 m). Therefore, the Tancheng Lujiang fault zone is an important inversion tectonics situating in eastern Asia. The erosion depth is merely about 1～3 km,as the formation of the fault zone was slightly eroded. Thus the outcropping fault rocks comPOsed of the cataclasite and gouge along the fault zone. An imPOrtant endogenic metallic mineralization zone of eastern China was formed in the Early Cretaceaus.
出处
《现代地质》
CAS
CSCD
1996年第2期159-168,共10页
Geoscience
基金
地质矿产部"八.五"重要基础地质科研基金
关键词
断层长度
切割深度
断距
郯庐断裂带
形成
演化
fault length
penetration depth
slip displacement
inversion tectonics
paleostress
Tancheng-Lujiang fault zone
