摘要
光泽—武平断裂带南端控制着白垩纪盆地的形成与展布,发育韧性向脆性的演化过程。运用LA-ICP-MS技术对断裂带下盘糜棱岩化花岗岩进行锆石U-Pb测年,获得(128±1.4)Ma的成岩年龄,结合断裂带上盘为未变形的早白垩世寨下组,限定了韧性剪切活动发生在早白垩世中期。古构造应力场反演显示:晚中生代该断裂经历"手拉风琴式"的NW-SE向的主构造应力场作用,且晚白垩世应力场发生顺时针旋转,记录了古太平洋和新特提斯2大构造域对福建大陆的交替影响和复杂的陆缘板块动力学过程。
The southern end of Guangze-Wuping fault belt,which controlled the formation and distribution of Cretaceous basin,was developed the evolution process from ductile to brittle.LA-ICP-MS technique was used to date the zircon of mylonitized granite in the lower wall of the fault zone,and the diagenetic age of(128±1.4)Ma was obtained.Combined with the fact that the upper wall of the fault is the undeformed Zhaixia Formation of early Cretaceous,the ductile shear activity occurred in the Mid Early Cretaceous.Inversion of paleotectonic stress field shows that,since the late Mesozoic,the fault has undergone the NW-SE stress field and rotated clockwise in Late Cretaceous,which recorded the alternating influence of Paleo-Pacific and the Neo-Tethys tectonic systems on Fujian continent and the complex continental margin plate dynamics process.
作者
薛德杰
Xue Dejie(Fujian Institute of Geological Survey and Research,Fuzhou,350013)
出处
《福建地质》
2019年第4期263-277,共15页
Geology of Fujian
基金
中央财政项目“武夷山成矿带龙泉—上杭地区地质矿产调查”(编码:DD20160037).
