【摘要】 文章在详细的野外地质调查研究基础上,对徐淮地区古生界和上元古界构造变形进行了研究和分析,发现古生界与上元古界变形特征有着明显的差异。古生界以强烈、紧闭或倒转褶皱为主,经统计分析,这些褶皱轴面多向南东倾斜,与此相伴生有一系列由南东向北西逆冲的冲断构造;地层缩短量达40.5%~62.4%。而上元古界的构造变形相对较弱,以宽缓的褶皱为主,断裂活动以顺层滑动和小型脆性断层为主,总体上构成侏罗山式构造组合(其中以隔档式为主要表现形式),经平衡剖面估算,其上元古界变形缩短量为15%左右。研究认为上元古界为强干层,沿其上下层面均产生剪切滑动,受其影响自身沿基底滑脱发育了侏罗山式褶皱构造组合,而沿其上层面的滑动为古生界的的大规模伸展滑覆提供了充要条件。更多还原

【Abstract】 Based on the detailed geological field investigation,the Paleozoic and Upper Proterozoic tectonic deformation in Xu-Huai region was studied,and the significant difference between the Paleozoic and Upper Proterozoic deformation characteristics was found.The Paleozoic was based on a strong,closed or overturned fold.The statistical analysis results showed that these fold axial planes mostly tilted to the south east,and were accompanied by a series of thrust structures with thrusting from south east to north west.The stratigraphic shortening amount was up to 40.5%-62.4%.The Upper Proterozoic tectonic deformation was relatively weak,with wide and gentle folds mainly faulting to slide along the floor and small brittle faults,and mainly constituted Jura tectonic portfolio in which the kicker manifestation was the main type.The shortening amount of Upper Proterozoic was about 15%according to the balanced section estimation.It is suggested that the Upper Proterozoic is a strong dry layer along with both the upper and lower levels of shear slip,and with the basal detachment,it has developed the Jura folds tectonic portfolio,while sliding along the upper level provides the necessary and sufficient condition for the massive stretch slip cover of Paleozoic.更多还原