發(fā)布時間：2018-04-15 10:20

  本文選題：熱林鉬銅礦床 + 流體包裹體��； 參考：《中國地質(zhì)大學(北京)》2017年碩士論文

【摘要】：熱林鉬銅礦床是近年來在義敦地體南部新發(fā)現(xiàn)的較大的一個斑巖型礦床。礦床具有明顯的上銅下鉬特征,作者根據(jù)巖相學特征劃分成礦期次,利用流體包裹體顯微測溫、激光拉曼以及氫氧同位素測試來分析成礦流體的來源、演化以及鉬與銅的分離機制,得到基本結(jié)論如下:1、礦體全部位于二長花崗斑巖中,其成礦作用可劃分為四個階段:硅酸鹽-氧化物(Si-O)階段,石英-輝鉬礦(Qtz-Mo)階段,石英-黃銅礦(Qtz-Cu)階段,碳酸鹽巖(C)階段。2、礦床發(fā)育四種包裹體:氣液兩相(VL)型,富氣相(LV)型,含NaCl子晶三相(SL)型和含CO2三相(LC)型。Si-O階段發(fā)育VL、LV與LC型,多為LV型;Qtz-Mo階段和Qtz-Cu階段皆發(fā)育全部四種包裹體,但前者LC型含量少于后者;C階段發(fā)育VL與LV型,多為VL型。3、各階段成礦流體均一溫度依次為374.8~501.7℃,290.7~482.3℃(主要為380~440℃),268.2~462.8℃(主要為320~380℃),182.3~279.5℃。均一溫度呈現(xiàn)依次變低的趨勢,且在階段之間存在重合,指示流體演化是連續(xù)的。4、Si-O階段,成礦流體源于初始巖漿流體;Qtz-Mo階段,流體主要是巖漿水,并有沸騰作用發(fā)生;Qtz-Cu階段混入了大氣降水并也有沸騰作用發(fā)生;C階段的流體是巖漿水與大氣降水的混合物。5、Si-O階段流體高溫富堿,為相對氧化環(huán)境;Qtz-Mo階段為中高溫、高酸度的相對還原環(huán)境;Qtz-Cu階段為中低溫、低酸度的相對氧化環(huán)境。成礦流體的氧化還原環(huán)境、酸堿度以及溫度隨時間的變化使得熱林鉬銅礦床的鉬與銅在不同的時間沉淀,而礦床上銅下鉬的空間差異是由流體的溫度、鉬與銅對硫的爭奪以及流體不混溶(沸騰作用)引致的。
[Abstract]:The hot forest molybdenum copper deposit is a large porphyry deposit discovered recently in the southern part of the Yidun terrane.The ore deposit has obvious characteristics of upper copper and lower molybdenum. According to the petrographic characteristics, the authors divide the ore forming stages into stages, and analyze the source of ore-forming fluids by using fluid inclusion microthermometry, laser Raman and hydrogen and oxygen isotopic measurements.The basic conclusions are as follows: 1. The orebodies are all located in the Erchang granitic porphyry. The ore-forming process can be divided into four stages: silicate-oxide Si-O stage, quartz-molybdenum stage, and quartz-molybdenum stage.Quartz-chalcopyrite (Qtz-Cu) stage, carbonate rock (C) stage. 2. There are four types of inclusions developed in the deposit: gas-liquid two-phase (VLV) type, gas-rich gas phase (LVL) type, NaCl sub-crystalline three-phase (SLL) type and CO2 three-phase (LCL) type. Si-O stage develops VLLV-LC type.Most of the inclusions developed in the LV type Qtz-Mo stage and the Qtz-Cu stage, but the content of the LC type in the former type was lower than that in the latter stage, which developed VL and LV type.The homogenization temperature of the ore-forming fluid in each stage is 374.8501.7 鈩，

本文編號：1753705