大渡河金矿田喜马拉雅期成矿的^(40)Ar/^(39)Ar年龄依据及其意义  

(40)~Ar/(39)~Ar Dating of the Daduhe Gold Orefield in Kangding, Sichuan -New Evidence of the Himalayan Mineralization and Its Implications

作　　者：闫升好[1] 杨建民[1] 王登红[1] 陈毓川[1] 徐珏[1] 

机构地区：[1]中国地质科学院矿产资源研究所,北京100037

出　　处：《地质学报》2002年第3期384-388,共5页Acta Geologica Sinica

基　　金：国家重点基础研究项目(编号 G1999043203);地质大调查项目(编号K1.4-3-4)资助成果。

摘　　要：大渡河金矿田是扬子地台西南缘一个重要的金成矿集中区。对其中白金台子和三雕两个金矿床含金石英脉的石英进行了^(40)Ar/^(39)Ar快中子活化法同位素年龄测试,获得坪年龄分别为25.4±0.2 Ma和24.7±0.3Ma,相应的等时线年龄分别为24.1±0.1 Ma和22.9±0.1 Ma,反等时线年龄分别为23.8±0.1 Ma和23.0±0.1Ma。这些年龄数据不仅有力地证明了大渡河金矿形成于喜马拉雅构造期,也为更好地认识扬子地台西南缘金矿形成的地质构造背景、矿床成因及成矿规律,进而指导区域找矿提供了依据。The Daduhe gold orefield are one of the most important gold metallogenic areas on the southwestern mar-gin of the Yangtze platform, but there are disputes in the genesis of the orefield, particularly due to lack of data on its accurate ore-forming age. Through field investigations and isotope chronological studies, the authors have obtained a group of Ar/Ar chronological data of the auriferous quartz, i. e. , a plateau age of 25. 4 ± 0. 2 Ma, and isochronal and reverse isochronal ages of 24. 1 ± 0. 1 Ma and 23. 8 ± 0. 1 Ma respectively are obtained for the auriferous quartz from the Baijintaizi deposit; and a plateau age of 24. 7 ± 0. 3 Ma, and isochronal and reverse isochronal ages of 22. 9 ± 0. 1 Ma and 23. 0 ± 0. 1 Ma respectively obtained for the quartz from the Sandiao de-posit. These isotope data suggest that the Daduhe gold orefield were formed during the Himalayan and provide important evidence for the view that the mineralization was closely related to the Himalayan magmatism and brittle-ductile shearing, and therefore the Daduhe gold mineralization belt is surely an organic part of the Ceno-zoic Cu-Pb-Zn-Au metallogenic system in the Sanjiang(means three rivers, i. e. : Jinsha River, Nujiang River and Lancang River) area, southwestern China.

关 键 词：金矿田 喜马拉雅期 ^40AR/^39AR年龄 地质构造 成矿规律 氩同位素 快中子活化法 

分 类 号：P618.51[天文地球—矿床学]