鄂西白垩纪远安盆地的变形带构造

鄂西白垩纪远安盆地中大量发育变形带及其密切相关的断层,主要分为两期,早期为带有正断性质的北北东向组变形带及简单的正断层,形成在同沉积或早成岩阶段,而晚期为带走滑性质的北-南向组和北东向组变形带及复活断层,形成在白垩纪以后.根据实测的共轭变形带和断层滑动数据,古应力分析的结果表明,早期为北西西-南东东向拉张的伸展状态,而...

Deformation bands in the Cretaceous Yuanan Basin, western Hubei, central China

A variety of deformation bands and faults exist in the Cretaceous Yuanan Basin in the west of Hubei Province，China.Most of them formed at two stages，according to the abutting or cutting relationship.NNE striking deformation bands with a normal sense，as well as normal faults were produced in the time of deposition or early digenesis at the earlier stage，while N S and NE striking deformation bands with a strike slip sense，together with reactivated faults were generated at the later stage.Based upon conjugate deformation bands and fault slip data measured in the field，palaeostress analysis was performed.The results indicate the existence of tension in the earlier stage，and of compression in the later stage.The earlier extension，directed from NWW to SEE，was consistent with the regional extensional regime in the Cretaceous.The later compression directed from N to S has nothing to do with the Late Paleogene inversion of the Jianghan Basin，of which the Yuanan Basin was once a part on the northwest，by the compression perpendicular to it.It might have been resulted from the tectonogeny having a roughly similar direction at the end of the Paleogene.