Late Mesozoic and Cenozoic thermotectonic evolution along a transect from the north China craton through the Qinling orogen into the Yangtze craton, central China
Late Mesozoic and Cenozoic thermotectonic evolution along a transect from the north China craton through the Qinling orogen into the Yangtze craton, central China
复制标题
DOI：
10.1029/2006tc001985
复制
发表时间：
2006-12-22
期刊：
影响因子：
4.2
通讯作者：
Gleadow, Andrew J. W.
中科院分区：
文献类型：
--
作者：
Hu, Shengbiao;Raza, Asaf;Gleadow, Andrew J. W.
[1]白垩纪和新生代华北-扬子板块之间的三叠纪秦岭-大别造山带的复活是太平洋俯冲-弧后伸展作用和西部碰撞作用共同作用的结果。本文报道了东秦岭沿着一条长达400 km的南北向剖面的磷灰石裂变径迹和磷灰石、锆石（U-Th）/He数据。时代显示出向北迁移的一般模式。三个主要的冷却阶段被定义为多个热年代学数据集建模。第一阶段发生在晚三叠世-早侏罗世，与三叠纪扬子俯冲和武当变质核杂岩的折返有关。第二个阶段代表100和60 Ma之间的区域折返，与中国东部晚白垩世-始新世（K-2 - E）红层沉积的裂谷同时代，可能表明与中国东部太平洋俯冲-弧后伸展有关;然而，它也可能被拉萨-西缅甸-羌塘-印度支那碰撞造成的东向构造逃逸叠加。第三次冷却期大约在45 Ma左右开始，仅在北秦岭和小秦岭渭河地堑正断层下盘开始。我们认为第三阶段与秦岭断裂系统的复活有关，这是由于印度-亚洲碰撞造成的东向构造逃逸的结果。
[1] Cretaceous and Cenozoic reactivation of the Triassic Qinling-Dabie orogen between the north China and Yangtze cratons resulted from the combined effects of Pacific subduction - back-arc extension in east China and collisions in west China. We report new apatite fission track and apatite and zircon (U-Th)/He data from east Qinling along a > 400-km-long N-S transect from Huashan through the Qinling orogen to Huangling. The ages show a general pattern of younging northward. Three major cooling phases are defined by modeling the multiple thermochronologic data sets. The first phase occurred locally in the North and South Qinling during the late Triassic to early Jurassic, following heating associated with the Triassic Yangtze subduction and exhumation of the Wudang metamorphic core complex on the cratonal edge. A second phase represents regional exhumation between 100 and 60 Ma, coeval with rifting marked by the Late Cretaceous - Eocene (K-2 - E) red bed deposition in eastern China and possibly indicating a link with Pacific subduction - back-arc extension in eastern China; however, it may also have been superimposed by eastward tectonic escape resulting from the Lhasa - West Burma - Qiangtang-Indochina collision. The third cooling phase was initiated at similar to 45 Ma exclusively in the north Qinling and in the footwall of the graben-bounding normal fault of the Weihe graben in the Lesser Qinling. We suggest the third phase was related to reactivation of the Qinling fault system as a result of eastward tectonic escape imposed by the India-Asia collision at similar to 50 Ma.