滇西北兰坪金顶铅锌矿床有机物质地球化学  

Geochemistry of organic matters in the Jinding zinc-lead deposit, Lanping Basin, Northwest Yunnan Province

作　　者：高永宝[1,2] 薛春纪[3] 曾荣[4] 

机构地区：[1]西安地质矿产研究所 [2]长安大学资源学院,陕西西安710054 [3]中国地质大学地质过程与矿产资源国家重点实验室 [4]长安大学资源学院

出　　处：《地球化学》2008年第3期223-232,共10页Geochimica

基　　金：国家自然科学基金(40472054,40272050);国家重点基础研究发展计划项目(2002CB4126007)

摘　　要：兰坪盆地以及金顶铅锌矿床存在大量不同形式、成熟度的有机物质。从兰坪盆地到金顶矿区,岩石、矿石中有机物质含量增加明显,金顶矿区矿石及其围岩中有机物质热成熟显著。金顶矿区有机物质的地球化学特征显示,有机物质烃源母质主要为菌藻类,属Ⅰ型有机质,烃源母质经历了强还原的高盐度环境;有机物质的铅同位素表明矿区的沥青主要来源于盆地的有机物质,是其经过漫长的地质演化演变而来的;碳同位素以生物有机成因碳为主,说明有机物质与金属成矿具有密切的联系。盆地演化尤其是在金顶局部穹隆化过程中可能聚集起来的油气藏是金属大规模快速沉淀的重要还原剂。There are a lot of organic matters in different forms or maturity in the Jinding zinc-lead deposit and Lanping basin. The content of organic matter increases obviously from Lanping basin to Jinding deposit and the organic matters in the ores and wall-rocks in the Jinding deposit are in mature and high-mature stages. The geochemical characteristics of the organic matters in the deposit show that the organic matters of the source rocks were mainly derived from bacteria and algae, and are type- Ⅰ organic matter. The source rocks experienced high reduction evolution and in the high salinity environments. The Pb isotopic compositions indicated that the bitumen in the ore district was derived from the organic matters in the Lanping basin. The C isotopic compositions showed that the organic matters were closely related to metal mineralization. During the process of basin evolution, hydrocarbon reservoir formed in the Jinding dome is the reducer of rapid metal mineralization.

关 键 词：生物标志化合物 碳同位素 铅同位素 有机物质 金顶铅锌矿床 兰坪盆地 

分 类 号：P593[天文地球—地球化学] P597[天文地球—地质学]