摘要
在前人工作基础上,文章综述了新疆阿尔泰铁矿地质特征和成矿背景。新疆阿尔泰铁矿赋矿地层主要为上志留统—下泥盆统康布铁堡组、中上泥盆统阿勒泰镇组和中泥盆统北塔山组,少数为下石炭统和下古生界。成因类型可划分为火山岩型、矽卡岩型、伟晶岩型、与花岗岩有关的热液型、与基性岩体有关的钒钛磁铁矿型和砂矿型6种,其中火山岩型和矽卡岩型为主要类型。火山岩型铁矿主要分布于克兰盆地的康布铁堡组上亚组中;矽卡岩型铁矿分布在麦兹盆地康布铁堡组下亚组、加尔巴斯岛-科克布拉克一带阿勒泰镇组和乔夏哈拉-老山口一带的北塔山组中;与花岗岩有关的热液型铁矿分布于额尔齐斯剪切带中。根据同位素测年结果,铁矿成矿时代分为4期:早泥盆世(410~389 Ma左右)、中泥盆世(380~377 Ma)、早二叠世(287~274 Ma)和早三叠世(244 Ma)。同位素组成表明,阿尔泰铁矿的硫主要来自火山岩、闪长岩、花岗岩和细菌还原海水;岩(矿)石稀土元素特征表明成矿物质主要来自基性火山岩。
This paper has dealt with the geological characteristics of iron deposits in Altay of Xinjiang in their metallogenic-tectonic contexts.The main host rocks for iron deposits in that region are the Upper Silurian-Lower Devonian Kangbutiebao Formation,Middle-Upper Devonian Altaizhen Formation and Upper Devonian Beitashan Formation,with minor Lower Carboniferous strata.These iron deposits can be divided into such types as volcanic rocks,skarn,pegmatite,granite-related hydrothermal solution,basic pluton-related V-Ti-magnetite and placer,with the volcanic rocks and skarn types being predominant.The volcanic rocks type iron deposits are mainly located in the Upper Kangbutiebao Formation in the Kelan volcanosedimentary basin.The skarn type iron deposits occur primarily in the Lower Kangbutiebao Formation in the Maizi volcano-sedimentary basin,Altaizhen Formation in Jiaerbasidao-Kekebulake and Beitashan Formation in Qiaoxiahala-Laoshankou.The granite-related hydrothermal iron deposits occur primarily along the Ertix shear belt.Based on isotopic age data,the authors hold that iron deposits in Altay were essentially formed in four periods: Early Devonian(410~386 Ma),Middle Devonian(380~377 Ma),Early Permian(287~274 Ma),and Early Triassic(244 Ma).Sulfur isotopic compositions from the iron deposits in Altay imply that the sulfur was derived from volcanic rocks,diorite,granite and bacteria reduction of sulfate from seawater.REE geochemistry of rocks and ores from the iron deposits in Altay suggests that the ore-forming material was derived from the basic volcanic rocks.
出处
《矿床地质》
CAS
CSCD
北大核心
2011年第4期575-598,共24页
Mineral Deposits
基金
"十一五"国家科技支撑计划重点项目(编号2006BAB07B02-01)
国土资源大调查项目(编号1212010786006)
国家自然科学基金项目(编号40672065)联合资助成果
关键词
地质学
铁矿
时空分布
地质特征
成矿作用
阿尔泰
新疆
geology
iron deposits
time-space distribution
geological characteristics
metallogenesis
Altay
Xinjiang