地质科技情报2013，Vol.32Issue(1)：71-79,9.
黔北铝土矿不同类型矿石地球化学特征及其对成矿作用的指示
Geochemistry of Varied Type Ores of Northern Guizhou Bauxites and its Implication for Mineralization
摘要
Abstract
The Wuchuan-Zheng'an-Daozhen bauxite zone is one of the major Al-rnetallogenic belts in China. The bauxite deposits dominantly comprise four ore types featured by massive, brecciated, pisolitic to oolitic and earthy structures respectively. This study presents a comprehensive element geochemical study of the distinct ores, underlain high-Al claystone and Silurian shales of the Hanjiadian Formation by elemental mass balance modeling, and then the ore genesis is discussed. It is suggested that the metallogene-sis occurred at a broad coastal plain and was closely related with seawater encroaching upon the weathering profiles along continental margin by multiple marine transgression-regression recycling. Reduction condition during transgression resulted in formation of a large amount of pyrite-dominated sulfides under a certain depth range of the weathering profiles, whereas the oxidation reaction during regression produced strong sulfuric acid aqueous solution, which carried out a large quantity of matrix elements and advanced bauxitization. It is further suggested that the massive ore, featured by relatively high impurity, was formed by chemical precipitation when the matrix-bearing aqueous solution evolved toward a pH neutralization and oxygen fugacity decreasing, whereas the earthy ore is the end product of Al-purification by the multiple transgression-regression recycling.关键词
黔北/铝土矿/矿石类型/地球化学/成因Key words
northern Guizhou Province/ bauxite deposit/ ore type/ geochemistry/ metallogenesis分类
天文与地球科学引用本文复制引用
张莹华,凌文黎,吴慧,张亚男,丁晓英,崔滔,杜远生,雷志远,翁申富..黔北铝土矿不同类型矿石地球化学特征及其对成矿作用的指示[J].地质科技情报,2013,32(1):71-79,9.基金项目
贵州省地勘基金项目"贵州务正道地区铝土矿基础地质与成矿规律研究" （）
