青海长征沟地区铁矿床地质特征及成因探讨  

Discussion on geological characteristics and genesis of iron deposits in Changzhenggou,Qinghai Province

作　　者：韩敏强[1] 王亚红[1] 李莹[2] 

机构地区：[1]中国煤炭地质总局航测遥感局,西安710199 [2]中国石油长庆油田分公司勘探开发研究院,西安710018

出　　处：《中国地质调查》2017年第6期24-32,共9页Geological Survey of China

基　　金：中国地质调查局"青海省大柴旦镇长征沟地区铁矿调查评价(编号:12120113029200)"项目资助

摘　　要：青海长征沟地区铁矿床位于南祁连地块与柴达木地块拼接部位北缘,是近年来发现的一个重要铁矿床。为查明该地区铁矿床特征及成因类型,主要通过地质学手段进行详细的地质调查研究,为后续区域地质矿产工作规划部署和矿产勘查提供依据。研究表明:区内主要出露滩间山群安山玄武岩地层,区域变质程度较低,多表现为微弱的绿帘石化;在西部黑山泉及藏羊沟中段局部夹含透镜状大理岩,普遍发育矽卡岩化,代表性蚀变有透辉石化、绿帘石化及石榴子石化等,局部发育矽卡岩型磁铁矿;侵入岩发育,从基性到酸性均有出露,北部以基性为主,向南逐渐过渡为(中)酸性侵入岩为主。因此认为该矿床属于与中酸性侵入岩有关的矽卡岩型铁矿床,并指出岩性、构造、蚀变和物探4种找矿标志。Changzhenggou iron deposit,an important iron deposit found recently,is located in northern margin of the collision belt of Qaidam block and South Qilian block. In order to find out the deposits characters and genesis,the authors carried out the geological survey of iron deposit by geological means,and the results could provide some reference for the deployments planning of regional geology and mineral resources and mineral exploration.The results show that the main group is Tanjianshan Group with low metamorphic degree and weak epidotization in the study area. In the western part of the Heishanquan and the middle part of Zangyanggou,the strata are lentoid marble with the wide skarn petrification and few skarn-magnetite. The main alteration includes four types of skarntype magnetite,such as diopside,epidotization,garnet petrification etc. The intrusive rocks are widely developed in the study area,where the outcrops range from basic rocks to acidic rocks. The northern part is dominated by basic intrusive rocks and the rocks transform southwards to acidic( middle) intrusive rocks. The iron deposits are the skarn type iron ore deposits related to the middle acidic intrusive rocks,and the prospecting criteria of lithology,structure,alteration and geophysical prospectin were summarized.

关 键 词：磁铁矿 浸染状 绿泥石化 滩间山群 铁矿床 玄武岩 矽卡岩化 矿床地质特征 矽卡岩带 绿帘石化 侵入岩 矿石结构 成因探讨 

分 类 号：P618.31[天文地球—矿床学]