格陵兰伊苏亚铁矿床研究新进展  

New Research Progress of Isua Iron Deposit in Greenland

作　　者：柳建平[1,2] 赵元艺[3] 杨永强[1] 

机构地区：[1]中国地质大学,北京100083 [2]陕西省冶金矿山公司,西安710075 [3]中国地质科学院矿产资源研究所国土资源部成矿作用与矿产资源评价重点实验室,北京100037

出　　处：《地质科技情报》2013年第5期39-45,共7页Geological Science and Technology Information

基　　金：中国地质调查局项目“全球巨型成矿带区域构造与成矿地质背景对比研究”(1212011120326);中央地勘基金项目([2011]D3-09)

摘　　要：伊苏亚位于格陵兰岛西南努克市东北150km,条带状含铁建造（BIF）有9.61亿t资源量、铁平均质量分数36.48%。伊苏亚铁矿分布在3.8-3.7Ga的古太古代表壳岩带的东北方向。铁矿床赋存于变质火山岩系（绿岩系）和变质沉积岩的条带状含铁建造中。石英-磁铁矿型是已知6种条带状含铁建造中最主要的类型。条带状含铁建造中最常见的矿物组合是石英＋磁铁矿＋镁铁闪石（铁闪石）＋阳起石＋角闪石＋方解石。根据元素地球化学特征、稳定同位素数据认为BIF是海底火山喷发及热液蚀变外加后期构造改造共同形成的。伊苏亚铁矿在勘探过程中广泛使用了航磁、航电、高光谱测量、航空辐射,重力等技术,在现有矿体的西南和东边地区预测出新的靶区。Isua is located 150 km NE of Nuuk city, southwest Greenland. The Isua supracrustal belt contains 9610 million tons of handed iron formations （BIFs） with average content of 36.48% iron. Isua BIFs are distributed in the northeast of the 3.7--3.8 billion-year-old Archean craton, hosted in the metamorphic volcanic rocks （green stones） and meta-sedimentary rocks. On the basis of study on its field relationships, mineral assemblages, and chemical composition we recognized six major types of BIFs, and quartz-magnetite BIF is the major type. Quartz＋ magnetite ff-cummingtonite/grunerite ＋ actinolite＋ hornblende＋ calcite is the most common mineralogical assemblage in the BIFs. Based on the geochemical, isotope systematics data, it is argued that BIFs were derived from volcanogenic sources, seafloor hydrothermal alteration, and later stage structural transformation. During the Isua iron deposite exploration process, new methods based on aeromagnetic, electromagnetic, airborne hyperspectral scanning and radiometric surveys have been widely used. Additional exploration targets in the southwest and east regions of the Isua existing orebody have been recongnized.

关 键 词：伊苏亚 条带状含铁建造 矿物组合 BIF成因模式 

分 类 号：P618.31[天文地球—矿床学]