广西来宾市北敢堆积型铝土矿地质特征及找矿标志

Geological characteristics and prospecting mark of Beigan accumulation type bauxite deposit in Laibin City of Guangxi

在分析研究区域成矿地质背景、矿床地质特征的基础上,对矿床成因进行了初步探讨,总结了找矿标志。认为矿源层来自上二叠统合山组底部与中二叠统茅口组顶部的古侵蚀间断面上的原生铁铝岩(铝土矿);成矿过程经历了原生铁铝岩的形成、初始堆积铝土矿的形成和改造富集成矿三个阶段后再次遭受风化、剥蚀、搬运和堆积,最终堆积型铝土矿在岩溶坡地和丘陵等高地上分布较多,而在低洼处分布较少甚至未见出露。对矿区外围寻找新的堆积型铝土矿资源具有一定的指导意义。

On the basis of the analysis of regional and geological background of mineralization and geological characteristics of the deposit in the study area,the deposit genesis is preliminarily discussed.The prospecting marks are summarized.It is considered that the ore source layer is originated from the primary iron-aluminium rock(bauxite)on the paleoerosion discontinuity between the bottom of Heshan Formation of Upper Permian and the top of Maokou Formation of Middle Permian.The metallogenic process has experienced three stages,the formation of primary bauxite,the formation of initial accumulation of bauxite,and the transformation of enrichment and ore-formation.After that,it is weathered,eroded,transported and accumulated again.Finally,accumulated bauxite is generally distributed on karst slopes and hills and other highlands,but less or even none in low places.It has a certain guiding significance for finding new accumulation-type bauxite resources in the periphery of the mining area.