辽西阜新盆地及外围早白垩世火山岩锆石SHRIMP U-Pb定年及其对喷发期次的限定

火山岩时代和层位是资源勘探和沉积构造演化的基础性问题之一.阜新盆地构造位置属华北地块的东北端燕山褶皱带东部,早白垩世火山岩发育.该文通过在辽西阜新盆地及外围黑山-彰武地区系统采集了1套火山岩样品,测试锆石SHRIMP U-Pb同位素年龄.结合前人成果,提出区内白垩世的火山活动划分为5期,活动时间分别为(100±5)Ma...

Ziron SHRIMP U-Pb dating of Early Cretaceous volcanic rocks in Fuxin Basin and periphery, western Liaoning Province:Constraint on the eruption times

The age and horizon of volcanic rocks are the basic problems of resource exploration and sedimentary structure evolution. On the basis of field investigation, a set of volcanic rock samples have been collected in and outside Fuxin Basin, and the SHRIMP U-Pb isotopic age has been measured. Based on the test result, Cretaceous volcanic activities in western Liaoning Province can be divided into 5 times, which includes (100±5)Ma, (115±2)Ma, (122±2)Ma, (126±1)Ma and (132±1)Ma. In reference to field observation, the volcanic rock in Zhangwu-Heishan area includes 3 suites of early Cretaceous volcanic rock and 1 suite of Paleogene olivine-enclave-bearing basalt. The first set of volcanic rocks is middle basic basaltic andesite with fissure eruption, which can be seen in Shijiazi, Luotaishan, Zhangluotun, etc. the second set is medium coarse andesite, which can be seen in Halaheshao Jianshanzi, Huanghuashan, Xiashitu village in Cangtu countryside, etc., the third set is middle basic basaltic andesite with fissure eruption, which can be seen in Jianshanzi, Douyawopu, Xiashitu village in Cangtu countryside, etc. The age of alkali basalt in Paleogene is (56±2.9)Ma, which is distributed in Nalishan village, Shijiazi Town, Fuxin County.