同向断裂与反向断裂

同向与反向断裂是在伸展环境下的低序次张性断裂,一般规模较小。这些断裂产状相似、近于平行且成因相同,构成同向或反向断裂簇。根据控制断裂簇的高序次构造的不同,分为两种,一为断裂的倾向与所在地层倾向的相对关系而言,另一为断裂倾向与主干断裂倾向的相对关系而言。低序次断裂簇反映了高序次构造的特征与发育进程。前一类型的同向断裂簇增强构造的垂向幅度,反向断裂簇则降低构造的垂向幅度。后一类型的低序次断裂,其序次愈多,表明主干断裂发育的时间愈长,其形变历史也愈复杂。

SYNTHETIC AND ANTITHETIC FAULTS

Synthetic and antithetic faults are low-order and smallscale extension faults under extensional enviroment. These faults having similar growth shapes and same cause of formation nearly parallel each other and compose synthetic and antithetic fault families. According to difference in high-order structure controlling fault families, synthetic and antithetic faults are classified as two kindes. For one of which, the tendency of faults is related to the tendency of stratum where faults lie and for another, the tendency of faults is related to the tendency of main faults, loworder fault families reflect the features and development process of high-order structure. In the former ease, synthetic fault families enhance the vertical extent of the structure, whereas antithetic fault families lower the vertical extent. In the later case, the more orders low-order faults have, the longer the development duration of main fault lasts and the more complicated the deformation process is.