合肥盆地与大别—张八岭造山带的耦合关系

现今所见的大别—张八岭造山带是自印支期以来才形成的,其形成与演化对中、新生代合肥盆地的性质与演化起到了明显的控制作用.合肥盆地中、新生代不同时期的盆地类型及其改造形式与大别—张八岭造山带的活动形式存在密切的耦合关系:a)印支期(中晚三叠世)合肥盆地处表现的冲断改造与扬子板块—华北板块最终碰撞拼合并形成大别—张八岭造山带的同碰撞挤压逆冲造山相耦合;b)侏罗纪合肥类前陆盆地的形成与扬子俯冲板块的折沉所引发的大别—张八岭造山带的强烈浮力底辟造山隆升及扬子—华北陆块的进一步拼合挤压造山作用相耦合;c)早白垩世合肥滑覆-走滑复合盆地的形成与大别造山带的热隆伸展及张八岭造山带的走滑活动相耦合;d)晚白垩世早期合肥盆地大部表现为冲断改造及北东部形成坳陷盆地与大别造山带热隆伸展及张八岭造山带弱挤压作用相耦合;e)晚白垩世晚期—早第三纪张扭性裂陷盆地的形成与大别—张八岭造山带的造山后塌陷及断块差异升降运动相耦合;f)渐新世喜马拉雅运动主幕以来的大别—张八岭造山带总体表现为弱挤压-压扭造山隆升及逐渐被剥蚀夷平并为合肥盆地晚第三纪—第四纪坳陷型沉积提供物源.

COUPLING RELATIONS BETWEEN THE HEFEI BASIN AND THE DABIE-ZHANGBALING OROGENIC BELT

The existing Dabie-Zhangbaling Orogenic Belt, whose formation and evolution apparently controlled the features and evolution of the Meso-Cenozoic Hefei Basin, has been formed since the Indosinian epoch. There were close coupling relations between the basin types and its reforming styles of the Hefei Basin in the different periods of the Meso-Cenozoic and the moving styles of the Dabie-Zhangbaling Orogenic Belt: a) the coupling of the thrust reformation in the Indosinian (the Middle-Late Triassic) displayed in where the Hefei Basin is with the syncollision compressive obduction orogenesis which resulted in the final collision and matching of the Yangtze Plate and the Huabei Plate and the formation of the Dabie-Zhangbaling Orogenic Belt; b) the coupling of the formation of the paraforeland Hefei Basin in the Jurassic with the strong buoyancy diapir orogenic uplifting of the Dabie-Zhangbaling Orogenic Balt resulted from the folding subsidence of the underthrust Yangtze Plate and the further matching compressive orogenesis of the Yangtze-Huabei Landmass; c) the coupling of the formation of the slide-overlap and strike-slip composite Hefei Basin in the Early Cretaceous with the thermal-uplifting extension of the Dabie Orogenic Belt and the strike-slip movement of the Zhangbaling Orogenic Belt; d) the coupling of the thrust reformation displayed by the major Hefei Basin in the early stage of the Late Cretaceous and the formation of down-warped basins in the northeast part with the thermal-uplifting extension of the Dabie Orogenic Belt and the weak compression of the Zhangbaling Orogenic Belt; e) the coupling of the formation of tenso-shear rift basins in the late stage of the Late Cretaceous to the Paleogene with the postorogenic collapse of the Dabie-Zhangbaling Orogenic Belt and the differential elevation and subsidence of fault blocks; f) the Dabie-Zhangbaling Orogenic Belt since the main episode of the Himalayan movement in the Oligocene totally displaying weakly compressive and compresso-shear orogenic uplifting and being gradually denuded and leveled, and providing material sources for the down-warped deposition of the Hefei Basin in the Neogene-Quaternary.