吉黑地区晚古生代钼矿隆升剥蚀:地质与沉积物地球化学证据  

Late Paleozoic Molybdenum Ore Uplift and Erosion in Jilin and Heilongjiang Area:Geochemical Evidence of Geology and Sedimentary

作　　者：张海洪 付涛[2] 邓馨卉 迟唤昭 陈国强 苗长盛 ZHANG Haihong;FU Tao;DENG Xinhui;CHI Huanzhao;CHEN Guoqiang;MIAO Changsheng(Changchun Institute of Technology,Changchun 130021,China;Jilin Geological Survey Institute,Changchun 130061,China)

机构地区：[1]长春工程学院,长春130021 [2]吉林省地质调查院,长春130061

出　　处：《长春工程学院学报（自然科学版）》2024年第3期55-67,共13页Journal of Changchun Institute of Technology：Natural Sciences Edition

基　　金：吉林省自然科学基金项目(20220101178JC)。

摘　　要：吉黑东部尔站钼矿为晚古生代与酸性侵入体有关的小型钼矿,以此为代表的晚古生代钼矿是否经历抬升剥蚀的破坏尚不清楚。通过对古生代尔站钼矿与大兴安岭、小兴安岭和张广才岭中生代钼矿在水系沉积物和土壤中钼元素的地球化学特征发现,尽管古生代钼矿储量规模小,却表现出比中生代钼矿更大的地球化学异常的面积和更高的元素含量等特点。研究区经探槽和钻探工程揭示,成矿岩体蚀变显示为绿泥石化-绢云母化-黄铁矿化和钾长石化核心,符合斑岩型矿床模型的蚀变分带,但北东向矿体产状较平缓,矿体北部钾化核心埋藏较浅,结合在小兴安岭地区、桦南地区、大兴安岭地区等识别的隆升和剥蚀事件,表明以尔站钼矿为代表的晚古生代钼矿经历了中生代以来在小兴安岭—张广才岭的隆升剥蚀,导致矿体的部分剥蚀,形成的次生晕异常面积大,成矿元素含量高于大多数中生代钼矿,对晚古生代钼矿的保存产生了消极影响。The Erzhan molybdenum deposit in the eastern of Jilin and Heilongjiang is a small molybdenum deposit related to acidic intrusions in the Late Paleozoic era.It is unclear whether the Late Paleozoic molybdenum deposits represented by it have undergone uplift and erosion damage.Based on the geochemical measurements of sediments and soil elements in the water system,compared with the widely distributed Mesozoic molybdenum deposits in the Da Hinggan Mountains,the Xiao Hinggan Mountains,and the Zhangguangcai Mountains,the Paleozoic molybdenum deposits exhibit geochemical characteristics of Mo element in the water system and soil that inconsistent with the scale of the deposits,with large anomalous areas and high concent.Through exploration of trenches and drilling engineering in the research area,it has been revealed that the alteration of the mineralized rock mass is characterized by chloritization sericitization pyrite mineralization and potassium feldspar core,which is consistent with the alteration zoning of the porphyry deposit model.However,the northeast oriented ore body has a relatively gentle occurrence,and the potassium mineralization core in the north of the ore body is buried relatively shallow.Combined with the identified uplift and erosion events in area of the Xiao Hinggan Mountains,Huanan,and the Da Hinggan Mountains,it is indicated that the Late Paleozoic molybdenum deposits represented by the Erzhan molybdenum deposit have undergone uplift and erosion in the Xiao Hinggan Mountains-the Zhangguangcai Mountains since the Mesozoic era,resulting in the partial erosion of the ore body and the formation of a large area of secondary halo anomalies.The content of ore-forming elements is higher than that of most Mesozoic molybdenum deposits,which has a significant impact on the Late Paleozoic molybdenum deposits.The preservation has a negative impact.

关 键 词：钼矿 隆升剥蚀 地球化学 古生代 小兴安岭 张广才岭 

分 类 号：P59[天文地球—地球化学]