本文選題：師姑山鎢礦床　切入點(diǎn)：粵北　出處：《東華理工大學(xué)》2017年碩士論文

【摘要】：粵北師姑山鎢礦床位于南嶺中東段,該區(qū)鎢礦資源豐富,為“廣東始興鎢、錫礦礦集區(qū)”的重要組成部分。礦石類型屬石英脈型黑鎢礦,以石英大脈型、兼有細(xì)脈帶產(chǎn)出。本文基于總結(jié)師姑山鎢礦區(qū)地質(zhì)背景與成礦地質(zhì)特征,系統(tǒng)開展了元素地球化學(xué)、流體包裹體以及穩(wěn)定同位素地球化學(xué)研究,綜合以上分析礦床的成礦物質(zhì)、成礦流體的來源,探討礦床的成因,得出如下主要認(rèn)識(shí):(1)師姑山燕山期花崗巖具有富硅、富堿、弱過鋁質(zhì)、高分異的特征,具有殼源特征;花崗巖具有大離子親石元素Rb、Cs、K富集,高場強(qiáng)元素Th、U、Pb、Li含量高,Sr、P、Ti明顯虧損的特征;稀土元素總量在106.8×10-6~163.9×10-6之間,平均135.8×10-6,輕稀土元素相對富集,Eu明顯虧損,稀土元素分布模式圖呈現(xiàn)為左右基本對稱的“V”字型。(2)寒武系的淺變質(zhì)巖─板巖是師姑山礦床的重要的圍巖。板巖的微量元素地殼豐度標(biāo)準(zhǔn)化蛛網(wǎng)圖顯示,板巖中W、Sn、Pb、Zn、Bi等成礦元素顯著富集。(3)黃鐵礦微量元素?cái)?shù)據(jù)顯示其屬于熱液成因,輝鉬礦微量元素?cái)?shù)據(jù)顯示其來自殼源。黃鐵礦的稀土元素分布型式圖與巖漿巖的相似,說明了成礦物質(zhì)繼承自礦區(qū)巖漿巖,輕稀土元素在輝鉬礦中相對強(qiáng)烈富集,說明流體中多含有還原性質(zhì)的氣相成分和CO2、Cl、F等成分。(4)流體包裹體研究顯示,礦區(qū)成礦溫度最為集中在180℃到360℃之間,具多峰值,說明師姑山鎢礦床形成中成礦流體作用具多期性;深部巖漿提供了成礦流體,且在流體的演化過程中,混入了如大氣降水等低溫低鹽度的流體;流體的鹽度、密度分別集中在2.5wt%~7.5wt%NaCleqv和0.80g/cm3~0.90g/cm3,均較低;通過計(jì)算得出師姑山鎢礦床成礦壓力集中分布在10MPa~35MPa,成礦深度集中在1.5km~4.5km之間。低溫低鹽的流體混入,沸騰作用的發(fā)生,說明成礦流體的溫度、壓力、化學(xué)成分等因素發(fā)生過顯著的改變,流體的這種變化可能會(huì)導(dǎo)致成礦元素卸載,進(jìn)而在合適位置聚集成礦。(5)穩(wěn)定同位素研究得出:δ34S值介于-0.4‰~1.0‰之間,平均值為0.5‰,數(shù)據(jù)近于零且分布集中,與深部來源硫的特征(0±3‰)相符合,說明硫的來源較為穩(wěn)定單一,且來自于深部;C-O同位素?cái)?shù)據(jù)顯示,成礦流體中的碳源自深部的巖漿水,混入了部分有機(jī)性質(zhì)的碳。(6)師姑山鎢礦床屬于典型的巖漿熱液礦床,燕山期的巖漿活動(dòng)主導(dǎo)了礦化作用發(fā)生。通過系統(tǒng)地對師姑山鎢礦床的區(qū)域地質(zhì)、礦床地質(zhì)、成巖成礦時(shí)代、控礦因素、成礦物質(zhì)與成礦流體的來源以及成礦機(jī)制等進(jìn)行研究探討,表明師姑山鎢礦床成礦物質(zhì)、成礦流體主要來自深源巖漿,寒武紀(jì)的變質(zhì)巖貢獻(xiàn)了一部分的成礦物質(zhì)。來自深源的巖漿可以直接帶來成礦物質(zhì);同時(shí)又為成礦物質(zhì)的活化、運(yùn)移提供了熱源與能量,進(jìn)而在適當(dāng)?shù)奈恢酶患恋沓傻V。
[Abstract]:The Shigushan tungsten deposit in northern Guangdong is located in the middle and eastern part of Nanling, which is rich in tungsten resources and is an important part of "Shixing tungsten and tin ore concentrated area in Guangdong".The ore type belongs to quartz vein type wolframite.Based on the summary of the geological background and metallogenic geological characteristics of the Sigushan tungsten ore area, a systematic study of elemental geochemistry, fluid inclusions and stable isotope geochemistry has been carried out in this paper.After discussing the genesis of the deposit, it is concluded that the Yanshanian granites in Shigu Mountain have the characteristics of rich silicon, alkali, weak peraluminous, high differentiation and crust origin, and that the granites are enriched with the large ion lithophile element RbCsfen K, and that the granites are rich in silicon, alkali-rich, weak peraluminous, and highly differentiated, and have the characteristics of crust origin.The characteristics of obvious depletion of high field strength element Th, U, Pb, Li, Sr, P, and Ti, the total amount of rare earth elements between 106.8 脳 10 ~ (-6) and 163.9 脳 10 ~ (-6) with an average of 135.8 脳 10 ~ (-6), and the relative enrichment of light rare earth elements, the depletion of EU is obvious.The REE distribution pattern is presented as a left and right symmetrical "V" zigzag.) the Cambrian shallow metamorphic rock-slate is an important surrounding rock of the Sigushan deposit.The normalized cobweb diagram of crustal abundance of trace elements in slate shows that the trace elements of WSn-Sn-PbPbZn-Bi are enriched significantly.) the data of trace elements of pyrite indicate that it belongs to hydrothermal origin, and the trace element data of molybdenum is from the crust source.The REE distribution pattern of pyrite is similar to that of magmatic rock, indicating that the ore-forming material inherits from the magmatic rock of the mining area, and the LREE is relatively strongly enriched in molybdenum ore.The results show that the ore forming temperature of the ore area is between 180 鈩，

本文編號(hào)：1687566