本文選題：東準噶爾 + 鉬礦　； 參考：《中國地質大學(北京)》2017年碩士論文

【摘要】：希勒庫都克鉬礦位于東準噶爾北緣,是東準噶爾出現(xiàn)的唯一一個斑巖型鉬礦。礦區(qū)主要侵入體為閃長玢巖、二長花崗巖、花崗斑巖及石英斑巖。其中鉬礦主要與準鋁質-弱過鋁質的鈣堿性-高鉀鈣堿性的花崗斑巖及二長花崗巖有關。含礦花崗巖類屬于I型花崗巖。石英斑巖、花崗斑巖及二長花崗巖的鋯石的U-Pb年齡分別為315.7±2.3 Ma、326.4±2.0 Ma、328.2±1.8Ma,形成于早石炭世晚期的后碰撞環(huán)境當中。二長花崗巖、花崗斑巖以及石英斑巖均具有相似的?Hf(t)值及年輕的二次模式年齡,其中?Hf(t)值分別為11.5-15.5、12.7-15.1、12.3-15.6,平均值分別13.9、14.1、14.0,二次模式年齡分別為388-601Ma、379-524Ma、328-545Ma,平均值分別為451Ma、435Ma、432Ma。二長花崗巖鋯石δ18O值為4.89-5.26、平均為5.03,花崗斑巖鋯石δ18O為4.84-5.18、平均值為5.07,石英斑巖鋯石δ18O值為4.29-5.08、平均值為4.85,含礦花崗巖與地幔中鋯石δ18O保持一致。礦區(qū)含礦巖體具有相似的微量、稀土元素分配圖及同位素特征,并且其主要元素在哈克圖解上顯示有規(guī)律的變化,說明礦區(qū)含礦巖體來源于同一個沒有被蝕變的年輕洋殼的部分熔融形成的巖漿連續(xù)演化產(chǎn)物,而沒有古老地殼及沉積物的加入。石英斑巖與含礦巖體具有相似的Hf同位素特征及時空上的緊密性,判斷其為與含礦巖體同一源區(qū)而不同背景下的產(chǎn)物。鋯石Ti溫度計算出來的巖石結晶溫度分別為:二長花崗巖為568-825℃、平均為728℃,花崗斑巖為:615-745℃、平均為719℃,石英斑巖為686-878℃,平均為777℃。二長花崗巖中鋯石CeIV/CeIII比值為25.61-141.45、平均值為71,巖體氧逸度為-7.5至-21.04、平均值為-12.20,花崗斑巖中鋯石CeIV/CeIII比值38-147.5、平均值為95,氧逸度為-8.62至-18.84之間、平均值為-12.80。貧礦石英斑巖中鋯石CeIV/CeIII比值6.21-42.77、平均值為23.97,氧逸度在-13.92到-19.02之間、平均值為-16.73。說明礦體形成于較高氧逸度條件下。希勒庫都克鉬礦含礦巖體形成于較高氧逸度條件下,而與中亞造山帶其他大型-超大型斑巖礦床相比,其氧逸度相對較低,說明希勒庫都克礦床大小可能被其源區(qū)氧逸度大小所控制。
[Abstract]:The Shilakuk molybdenum deposit is located in the northern margin of East Junggar and is the only porphyry molybdenum deposit in East Junggar. The main intrusions are diorite porphyrite, monzogranite, granitic porphyry and quartz porphyry. The molybdenum ore is mainly related to the granitic porphyry and monzomorphic granitic porphyry with quasi-aluminite and weak peraluminous and high potassium calc-alkaline. The ore-bearing granites belong to type I granites. The U-Pb age of zircon from quartz porphyry, granitic porphyry and monzomorphic granite is 315.7 鹵2.3 Ma-326.4 鹵2.0 Ma-328.2 鹵1.8 Ma. it was formed in the post-collision environment of late early Carboniferous. The monzomorphic granite, granitic porphyry and quartz porphyry have similar values of HfTO) and young secondary model age, among them, the values of HfTX) are 11.5-15.5U 12.7-15.112.3-15.6, the mean values are 13.9U 14.1U 14.0, and the secondary model ages are 388-601Ma379-524Ma328-545Ma.The average values are 451Ma-435Ma435Ma432Ma. the average values of the two types of granite are 11.5-15.55-15.112.3-15.60.The secondary model ages are 388-601Ma379-524Ma328-545Ma. the average values are 451Ma435Ma432Ma. The zircon 未 18O value of the monzogranite is 4.89-5.26, the average is 5.03, the zircon 未 18O of granitic porphyry is 4.84-5.18, the average is 5.07, the 未 18O value of quartz porphyry zircon is 4.29-5.08, the average value is 4.85. The zircon 未 18O of ore-bearing granite is consistent with 未 18O in mantle. The ore-bearing rock bodies in the mining area have similar trace, rare earth element distribution maps and isotopic characteristics, and their main elements show regular changes in the Huck diagram. The results show that the ore-bearing rock bodies in the ore area are derived from the continuous magmatic evolution of the same partially melted young oceanic crust without alteration without the addition of the ancient crust and sediments. Quartz porphyry and ore-bearing rock bodies have similar HF isotopic characteristics and spatio-temporal compactness, which are determined to be the products of different backgrounds in the same source area as the ore-bearing rock bodies. The crystallization temperatures calculated by zircon Ti temperature are 568-825 鈩，

本文編號：1943226