秦岭-大别造山带北部逆冲推覆构造与合肥盆地、周口坳陷控盆断裂

秦岭-大别造山带北部中-新生代逆冲推覆作用可划分出5个期次:即印支期(T₂-T₃)、燕山早期(J₂末-J₃)、燕山晚期(K₁末期)、燕山末期(K₂末期)和喜马拉雅早期(E末期)。合肥盆地、周口坳陷控盆断裂是秦岭-大别造山带北部逆冲推覆构造在盆地内的延伸,造山带与盆地逆冲推覆构造在时间序列上具有同步耦合性,在空间上具有密切相关性。逆冲推覆作用不仅控制了盆地的分布轮廓、构造格局、地层发育和沉积建造,而且还控制了盆地的形成与演化,决定了盆地的性质和类型。中生代盆山构造耦合是扬子、华北两板块碰撞、陆内俯冲断离和山脉隆升与伸展坍塌的地球动力学背景下形成的。古近纪末期逆冲构造形成机制与印度板块向欧亚板块之下俯冲的远程效应有关。

Overthrust tectonic in northern Qinling-Dabie orogenic belt and basin-controlling faults in Zhoukou depression and Hefei basin

Meso Cenozoic overthrusting in northern Qinling Dabie orogenic belt can be divided into five episodes,namely Indonisian(T 2 T 3),Early Yanshanian(end of J 2 J 3),Late Yanshanian(end of K1 ),End of Yanshanian(end of K 2)and Early Himalayan (end of E).The basin controlling faults in Zhoukou depression and Hefei basin are the extension of the overthrust tectonic in Qinling Dabie orogenic belt.The overthrust tectonics in the orogenic belt in the basin are characterized by their temporal synchrony and close spatial correlation.They would not only control the distribution pattern,structural framework,stratigraphic development and sedimentary formation of the basin,but would also control the formation and evolution of the basin and define the nature and type of the basin.The coupling of Mesozoic basin and range structures has been formed in the geodynamic setting of collision of Yangtze and North China plates,intracontinental subduction,and mountain uplift,extension and collapse.The overthrust tectonics at the end of Paleogene are related to the remote effect of subduction of Indian plate beneath Eurasian plate.