关键词: 松辽地块, 形变分析, 新生代, 构造应力场, 中生代

Abstract: By the analysis of deformation in outcrop area and fissure measurement of core rocks in Zhangqiang depression and its adjacent area, we divide the geological history of this region into eight tectonic stress phases and determine the tectonic stress states and deformation forms of each phase. We conclude that the tectonic stress fields of the late Jurassic and the Cretaceous resulted in the formation and development of faulted basins, and the stress state of the late Jurassic was nearly E-W extension. Between the end of Fuxin Group and the beginning of Quantou Group sedimentation stages, the stress fields resulted in the close of basin faulting stage and deformation of the late Jurassic caused by the change of stress states from E-W extension to E-W compression. In the Cretaceous phase, the principal stress direction was E-W compression which caused the regional depression as a whole in the early period and uplifting and erosion widely in the later time. The principal stress direction was NW-SE compression in the Eogene, and was NEE-SWW compression since the Neogene. Two phases of stress fields in Cenozoic only caused some reactive faults, the deformational strength was less than that in Jurassic and the Cretaceous.

Key words: Songliao Massif, Deformation analysis, Cenozoic era, Tectonic stress, Mesozoic era