本文選題：地球化學(xué) + 鎢鉬礦��； 參考：《中國(guó)地質(zhì)大學(xué)(北京)》2017年碩士論文

【摘要】：廣西博白-岑溪斷裂帶位于欽杭成礦帶南段,即是一條長(zhǎng)期活動(dòng)的地體邊界斷裂帶,也是一條巖漿活動(dòng)頻繁的W-Mo-Sn-Pb-Zn-Sb-Au-Ag多金屬成礦帶。文章以該帶中的廣西博白縣油麻坡矽卡巖型鎢鉬礦床為研究對(duì)象,主要研究了油麻坡鎢鉬礦床礦床地質(zhì)特征、礦床地球化學(xué)、成巖成礦年代等方面內(nèi)容,探討了油麻坡鎢鉬礦床的礦床成因,主要取得如下幾個(gè)方面的認(rèn)識(shí):1)油麻坡矽卡巖型鎢鉬礦床主要由矽卡巖型白鎢礦礦體組成。圍巖蝕變主要有矽卡巖化、硅化、大理巖化等。2)油麻坡礦床主成礦期原生流體包裹體主要有氣-液兩相、CO2三相包裹體、純液相包裹體這三種類型。流體形成溫度在157.9~444.5℃之間,峰值主要集中在300.0~325.0℃,平均溫度為318.9℃;流體鹽度范圍為5.11%~13.51%,峰值集中在7.0%~10.0%;礦床的流體密度平均密度為0.87g/cm3,表明油麻坡礦床成礦流體屬于中高溫中低鹽度體系。3)H、O同位素分析顯示,樣品的投影點(diǎn)均落在巖漿水范圍,表明油麻坡矽卡巖鎢鉬礦床的成礦流體主要來(lái)源于巖漿水。硫同位素研究結(jié)果表明,硫化物δ34S值顯示塔式分布特點(diǎn),δ34SV-CDT值分布范圍為0.5‰~4.1‰,平均值為2.45‰。推測(cè)油麻坡矽卡巖型鎢鉬礦體中硫化物的硫主要為深部巖漿來(lái)源。4)LA-ICP-MS鋯石U-Pb測(cè)年結(jié)果表明,油麻坡礦區(qū)深灰色花崗斑巖的等時(shí)線年齡為(479.7±3.9)Ma,灰色黑云母花崗閃長(zhǎng)巖為(109.7±1.1)Ma,淺灰色細(xì)粒白云母花崗巖為(103.3±1.2)Ma。輝鉬礦Re-Os測(cè)年獲得加權(quán)平均年齡為(97.4±1.9)Ma。由此可知,油麻坡巖體為一個(gè)復(fù)式巖體,存在兩期巖漿熱液活動(dòng),由早奧陶世(加里東期)的花崗斑巖、早白堊世(燕山晚期)的黑云母花崗閃長(zhǎng)巖和細(xì)粒白云母花崗巖組成,其中早白堊世的黑云母花崗閃長(zhǎng)巖是巖體的主體部分,細(xì)粒白云母花崗巖應(yīng)該是補(bǔ)體。鎢鉬礦形成于早白堊世晚期(即燕山晚期),與黑云母花崗閃長(zhǎng)巖和細(xì)粒白云母花崗巖密切相關(guān)。
[Abstract]:The Bobb-Cenxi fault zone in Guangxi is located in the southern section of Qinghang metallogenic belt, which is a long-active terrane boundary fault zone and a W-Mo-Sn-Pb-Zn-Sb-Au-Ag polymetallic metallogenic belt with frequent magmatic activity. Taking the oil-mapo skarn type tungsten and molybdenum deposit in Bobai County, Guangxi, as the research object, this paper mainly studies the geological characteristics, deposit geochemistry, diagenesis and metallogenic age of the oil-mapo tungsten and molybdenum deposit. In this paper, the genesis of the Yunmapo tungsten and molybdenum deposit is discussed. The main understanding is as follows: 1) the skarn type tungsten molybdenum deposit is mainly composed of skarn type scheelite ore bodies. The alteration of surrounding rock mainly includes skarnization, silicification, marble, etc.) the primary fluid inclusions in the main metallogenic period of the Youmapo deposit are mainly gas-liquid two-phase CO _ 2 three-phase inclusions and pure liquid fluid inclusions. The formation temperature of the fluid is between 157.9 鈩，

本文編號(hào)：1810184