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秦岭-大别造山带北缘新生代的推覆构造带位于宜阳、鲁山、确山、六安一线,由SW→NE依次逆冲叠置。滑脱面主要发育在上古生界软弱岩层或差异岩性的接触面上。在推覆构造的南侧,发育有东西向串珠状分布的变质核杂岩、NE向延伸的垒-堑构造组合、北宽南窄的楔形新生代盆地和正断层等。地球物理资料表明,宜阳、鲁山、确山、六安一线为向南倾斜的地球物理异常带。北部的华北地壳与南部的秦岭-大别地壳在视电阻率、地震反射波组、地震波速、流变学分层、地壳类型和岩石圈结构等方面,均有明显的差别。秦岭-大别造山带北缘新生代不同性质、有规律展布的构造,是中生代末期以来,华北板块相对于秦岭-大别造山带作巨型陆内俯冲的结果。
The Cenozoic nappe belt in the northern margin of the Qinling-Dabie orogenic belt is located in Yiyang, Lushan, Queshan and Lu’an first lines, and is successively thrust-superimposed by SW → NE. The detachment surface is mainly developed on the contact surface of the Upper Paleozoic weak rock or lithology. On the southern side of the nappe structure, there are metamorphic nuclear complexes with east-west beading distribution, basement-grab structure combination extended in NE direction, wedge-shaped Cenozoic basin with narrow north-south width and normal fault. Geophysical data show that Yiyang, Lushan, indeed Hill, Lu’an first line to the south slope of the geophysical anomaly. The North China crust in the north and the Qinling-Dabie crust in the south are obviously different in the aspects of apparent resistivity, seismic reflection wave group, seismic velocity, rheological stratification, crust type and lithosphere structure. Since the Late Mesozoic, the North China Plate relative to the Qinling - Dabie orogenic belt as a result of the giant intracontinental subduction of the Qinling - Dabie orogenic belt north of the Cenozoic of different nature, with regular distribution structure.