摘要
2008年以来,滇西澜沧老厂矿区深部新发现巨厚斑岩型钼矿体,找矿取得重大突破。在对矿区矿化系统结构研究的基础上,应用锆石SHRIMP U-Pb法和辉钼矿Re-Os同位素测年法对成岩和成矿进行精确定年。结果表明:成矿花岗斑岩体的形成年龄为(44.6±1.1)Ma;辉钼矿Re-Os等时线年龄为(43.78±0.78)Ma。证实矿区喜山期存在与隐伏花岗斑岩有关的大规模成矿作用,斑岩钼矿的成岩成矿期与滇西新生代岩浆作用高峰期吻合,老厂斑岩钼矿形成于陆内碰撞造山环境。
The Laochang region in western Yunnan is one of the areas with significant breakthrough for new discovery of great thick porphyry molybdenum ore bodies in the deep since 2008. On the basis of the analysis to mineralizing system texture, the rock- and ore-forming ages of the granite-porphyry and related molybdenum ores were precisely redefined by the SHRIMP zircon U-Pb and molybdenite Re-Os dating method. The results show that the age of ore-forming granite-porphyry is (44. 6±1.1 ) Ma, and the Re-Os isochron of molybdenites is (43.78 ± 0. 78 )Ma. It is suggested that a large-scale Mo (Cu)-mineralization exists in this region, which related to Himalayan concealed granite-porphyry, and consistent with the peak period of Cenozoic magmatism-mineralization in forming ages, and formed in intracontinental collision orogenic setting.
出处
《现代地质》
CAS
CSCD
北大核心
2009年第6期1049-1055,共7页
Geoscience
基金
国土资源部国家危机矿山接替资源勘查项目(200653056)
教育部专项项目(20089943)