矿床地质2013，Vol.32Issue(3)：591-602,12.
西南天山乌拉根铅锌矿床有机地球化学特征及其地质意义
Organic geochemistry of Wulagen Pb-Zn deposit in Southwest Tianshan Mountains and its implications
摘要
Abstract
The Wulagen lead-zinc deposit,located in Kashi Sag on the northwestern margin of the Tarim basin of Xinjiang,is hosted in Mesozoic-Cenozoic sandstones and conglomerates,where lots of organic matters are widely spread,such as residues of oil and gas and dry asphalt.This paper mainly presents analytical data of organic carbon,sulfur,chloroform bitumen "A" and its group composition,and saturated hydrocarbons detected by gas chromatography in ore bodies and host rocks,so as to better understand the roles of organic mater in the mineralization of lead and zinc.The results show that the composition of organic and sulfur in lead-zinc ores is relatively rich,suggesting that the lead-zinc mineralization was closely related to the reduction of oil and gas.The content of chloroform bitumen "A" in organic matter varies from 0.004 ％ to 0.025 ％.The ratio of total hydrocarbons is 46.22 ％ on average,that of "non-hydrocarbon + asphaltenes" is 53.77 ％ on average,and the average ratio of saturated hydrocarbons to aromatic hydrocarbons is 9.59,implying that the organic matter is similar to Ⅰ-type parent material.These characteristics suggest that the organic matter might have been sourced from the marine algae.The ratios of Pr/Ph in ores and rocks vary from 0.41 to 1.84,with 1.04 on average,indicating a deoxidization environment for the organic matter.Odd-even predominance indices (OEP) vary from 0.75 to 1.07,averagely 0.92,showing that the maturity of organic matter is relatively high.Carbon preference indices (CPI)are from 1.03 to 1.30,with 1.16 on average,indicating a higher degree in thermal evolution.Field evidence and analytical results of organic matter in ores and rocks suggest that the oil and gas took part in the lead-zinc mineralization,and the deoxidization of oil and gas played an important role in the deposition and enrichment of ore-forming elements such as lead and zinc.关键词
地质学/有机地球化学/铅锌矿床/乌拉根/西南天山Key words
geology/ organic geochemistry/ Pb-Zn deposit/ Wulagen/ southwest Tianshan Mountains分类
天文与地球科学引用本文复制引用
韩凤彬,陈正乐,刘增仁,陈柏林,崔玲玲,丁文君,蒋荣宝,李丽..西南天山乌拉根铅锌矿床有机地球化学特征及其地质意义[J].矿床地质,2013,32(3):591-602,12.基金项目
本文得到国家自然科学基金项目(41072071)、国家重点基础研究发展计划(973)项目(2007CB411305)、国家305项目(2011BAB06B05-03)、中国地质科学院地质力学研究所基本科研业务费项目(DZLXJK201209)和公益性行业科研专项(深部探测项目)(2011311191-02)的联合资助 （41072071）
