作　　者： ; ; ;

机构地区： 中山大学地球科学系

出　　处： 《地学前缘》 2011年第1期24-31,共8页

摘　　要： 中国东南部中生代发育有拗陷型、断裂型、断陷型3种不同类型的盆地,其中前者发育于晚三叠世—早侏罗世,其内多为含煤建造;次者发育于中侏罗世—早白垩世,主要为火山岩建造;后者发育于白垩纪—古近纪,主要为陆相红岩建造。研究结果表明,盆地构造类型的演化与该区中生代壳内岩浆层的演化密切相关。与联合古陆解体相伴随的古太平洋板块俯冲使得东亚陆缘岩石圈的内能逐渐升高,其结果是壳内岩浆层的形成和增厚以及其上盖层岩石的弯曲变形,导致中生代早期众多拗陷盆地的形成;燕山早期的构造运动使印支期已强烈变形的地壳进一步破裂,为壳内岩浆层的物质溢出或喷发提供了通道条件,从而在重熔界面(岩浆层上界面)埋深较浅的本区东部形成众多火山岩盆地;系统内能在晚侏罗世后逐渐下降,地壳冷却收缩使得断块的重力调整逐渐占主导位置,形成众多由正断层控制的断陷盆地。 Three different types of structural basins,i.e.down-warping,faulting and faulting-block basins were developed in the Mesozoic in Southeast China.The first type formed from the Late Triassic to the Early Jurassic with coal-bearing strata;the second formed from the Middle Jurassic to the Early Cretaceous with volcanic strata;and the last from the Cretaceous to the Paleogene time with continental red-bed.The formation of the three types of basins was closely related to the evolution of the Mesozoic intracrustal magma layer of this area.Subduction of the paleo-Pacific plate initiated at the Late Paleozoic increased the intrinsic energy of the lithosphere of this area,caused the formation and thickening of the intracrustal magma layer,brought on bending-deformation of the cover over the magma layer,and thus resulted in the formation of numerous down-warping basins in the earlier Mesozoic.Multi-crustal movements from the Indosinian to the Early Yanshanian period broke the crust and formed lots of faults that provided conduits for magma eruption and thus formed a series of volcanic basins controlled by faults in the eastern coastal area where the MI（Melting Interface understood as the upper face of the intracrustal magma layer） was imbeded relatively shallow.Decreasing intrinsic energy of the crustal melting system started at the end of the Late Jurassic and made the crust cool down and shrink,which resulted in fault-block movements under gravitation and thus produced lots of fault-block basins in the Late Mesozoic and the Early Cenozoic.

关 键 词： 中国东南部 中生代 壳内岩浆层 构造盆地

领　　域： [天文地球] [天文地球]