铜陵地区中酸性侵入岩年代学研究  

40 Ar/ 39 Ar Chronology of Intrusive Rocks from Tongling

作　　者：吴才来[1,2] 周打若 黄许陈[3] 张成火[3] 黄文明[3] 

机构地区：[1]中国地质科学院地质研究所 [2]中国地质大学 [3]安徽地矿局321地质队

出　　处：《岩石矿物学杂志》1996年第4期299-306,共8页Acta Petrologica et Mineralogica

摘　　要：本文选择了铜陵地区主要岩石类型的代表性岩体中黑云母为测定对象，准确地测定了侵入岩的４０Ａｒ／３９Ａｒ同位素年龄。测定结果表明，区内侵入岩的年龄均小于１４０Ｍａ，属燕山晚期的产物，后期热事件为成矿时代，晚于岩浆侵入时代，在此基础上，分析了ＫＡｒ法。Ar/ 39 Ar isotopic chronologic studies of intrusive rocks from Tongling area show that ages of these rocks are all younger than 140Ma and belong to Late Yanshanian period, with granodiorite, quartz monzodiorite, pyroxene monzodiorite and gabbro diabase being 139.8 137Ma, 137 135.8Ma, 138.2 136.6Ma and 133.7Ma respectively. On the basis of 40 Ar/ 39 Ar isotopic chronologic studies of these intrusive rocks, the authors have also dealt with their K Ar and Rb Sr isotopic ages, and pointed out that the age error was caused by the late hydrothermal alteration and the mixture between mantle magma and crustal magma. In addition, the mineralization ages are found to be close to the smaller ages in 40 Ar/ 39 Ar age spectra, which is in accord with the regional metallogenic character that mineralization took place later than magmatic activity.

关 键 词：氩同位素测井 侵入岩 年代学 铜陵地区 

分 类 号：P588.12[天文地球—岩石学]