印度尼西亚苏拉威西岛砾岩型红土镍矿床地质特征及成因  

Geological characteristics and genesis of gravel lateritic nickel deposit in Sulawesi,Indonesia

作　　者：程立群[1] 刘剑波[1] 任学义[1] 吴国学[2] 

机构地区：[1]河北省地矿局秦皇岛矿产水文工程地质大队,河北秦皇岛066001 [2]吉林大学地球科学学院,长春130061

出　　处：《世界地质》2015年第1期120-126,共7页World Geology

摘　　要：红土型镍矿是基性、超基性岩在热带、亚热带地区常年高温、多雨的环境下,经过风化--淋滤--沉积富集而成。基性、超基性岩是此类矿床的成矿母岩。因此,以往针对红土型镍矿的找矿勘探首先是寻找基性、超基性岩。笔者近期在印度尼西亚苏拉威西省Kolaka县发现了一种新型红土镍矿床,该矿床成矿母岩并非是基性、超基性岩,而是砾石成分以超基性岩为主的一套砾岩。为了区分传统意义上由基性、超基性岩风化淋滤形成的红土型镍矿,笔者将其称为砾岩型红土镍矿。该矿床的结构分带由上往下可分为:腐植土层、红土层、强风化砾岩层、半风化砾岩层、砾岩层,镍矿体主要分布于半风化砾岩层中。初步认为矿床是由砾岩经过风化--水解-淋滤-沉淀富集等作用形成的。Laterite nickel ore is produced by basic and ultrabasic rocks after weathering-leaching-deposition and enrichment in tropical and subtropical areas with high temperatures and rainy weather throughout the year. Basic and ultrabasic rocks are considered to be mineraliing mother rocks for rocks of this type. Therefore,looking for basic and ultrabasic rocks is the primary task to explore for laterite nickel ore in the past time. A new type of laterite nickel ore was discovered recently in Kolaka County of Sulawesi province,Indonesia. The ore-forming mother rocks are not basic or ultrabasic rocks,but a set of conglomerates consisting of dominated ultrabasic gravel. Gravel lateritic nickel deposit was named to distinguish from traditional laterite nickel ore resulted from basic and ultrabasic rocks after weathering and leaching. The structure of the deposit can be divided,in descending order,into humus layer,laterite layer,strongly weathered conglomerate layer,semi-weathered conglomerates,and conglomerates.The nickel ore body is mainly distributed in the semi-weathered conglomerate layer. It is preliminarily considered that the ore deposit was made from conglomerate after weathering-hydrolysis-leaching-sedimentary and enrichment.

关 键 词：砾岩型红土镍矿 地质特征 矿床成因 印度尼西亚 

分 类 号：P618.63[天文地球—矿床学]