本文選題：東天山 + 卡拉塔格礦集區(qū)　； 參考：《中國地質(zhì)大學(xué)(北京)》2016年博士論文

【摘要】：卡拉塔格礦集區(qū)梅嶺礦床位于新疆東天山地區(qū)吐哈盆地南緣的古生代卡拉塔格隆起帶的核部,在大地構(gòu)造位置上處于大南湖-頭蘇泉晚古生代島弧帶中段的火山盆地中,賦存于一套基性-中性-酸性火山巖-火山碎屑巖和次火山巖中,礦體主要由M1號礦體、M2號礦體和M12號礦體組成。梅嶺礦床M2號礦體的絹云母~(39)Ar-~(40)Ar同位素年齡為264.7±5.7Ma,礦化蝕變英安玢巖的成巖時代為(317.4±2.6)Ma,M12號礦體的礦化蝕變英安斑巖的成巖時代為313.0±6.5Ma,下盤的紫紅色英安巖的成巖時代為317.7±4.4Ma,限定了M12號礦體的成礦時代的下限。M1號礦體和M12號礦體的硫化物的Rb-Sr同位素等時線年齡分別為299.2±2.9 Ma和301.0±3.8 Ma,確定梅嶺礦床的成礦時代為石炭紀末期。梅嶺礦床中原生流體包裹體類型多為氣液兩相包裹體,個體較小,氣液比較小;流體包裹體均一溫度為117~238°C,鹽度為2.4%~9.3%,為中-低溫、中-低鹽度流體;成礦壓力為6.8~60.6 MPa,成礦深度約為0.2~2.0 km。流體包裹體氣相成分以H_2O為主,成礦流體屬H_2O-NaCl體系。成礦流體的δ~(18)O_(H_2O)為-5.75‰~-2.61‰,δD為-135.6‰~-117.2‰,表明成礦流體主要為巖漿水及大氣降水的混合水。梅嶺礦床M1號礦體主要硫化物的微量元素和稀土元素特征顯示其成礦流體為具弱還原性的富Cl流體,晚期成礦流體可能遭受了外來熱液的混入。微量元素含量特征及元素對的比值變化表明,梅嶺礦床應(yīng)為巖漿熱液成因,但其也受到火山作用疊加改造的影響。圍巖δ34S的范圍為1.4‰~4.4‰,主要硫化物δ~(34)S值的分布范圍為-1.6‰~4.8‰,表明S同位素來源可能為幔源硫和火山巖圍巖的混合硫。鉛同位素研究結(jié)果顯示出一定的幔源特征,為巖漿殼�；旌蟻碓�。依據(jù)前人研究成果,并結(jié)合本次的工作成果,建立了梅嶺低溫熱液礦床成礦模型。在總結(jié)區(qū)域成礦資料的基礎(chǔ)上,結(jié)合野外地質(zhì)調(diào)查和此次研究成果,提出了在卡拉塔格礦集區(qū)和大南湖島弧帶內(nèi)依據(jù)火山機構(gòu)特征、構(gòu)造特征、蝕變分帶明顯等特征是此類礦床的重要找礦標識。
[Abstract]:Meiling deposit is located in the core of the Paleozoic Karatagg uplift in the southern margin of the Turpan-Hami basin in the eastern Tianshan area, Xinjiang, and is located in the volcanic basin in the middle segment of the late Paleozoic island arc belt in Dananhu and Tou Suquan in the tectonic position. It occurs in a set of basic-neutral acid volcanic rocks volcanic clastic rocks and subvolcanic rocks. The orebody is mainly composed of M 2 ore body and M 12 ore body. The sericite ~ (39) Ar-~ (40) ar isotopic age of the M ~ (2) orebody in Meiling deposit is 264.7 鹵5.7 Ma.The diagenetic age of orebody M _ 2 ~ (39) Ar-~ (40) ar is 264.7 鹵5.7 Ma.The diagenetic age of orebody M _ (2) M _ (12) is 313.0 鹵6.5 Ma.The diagenetic age of fuchsia dolomite is 317.7 鹵4.4 Ma. The Rb-Sr isochron age of sulfides of M12 orebody and M12 orebody is defined as 299.2 鹵2.9Ma and 301.0 鹵3.8Marespectively. It is determined that the metallogenic age of Meiling deposit is the end of Carboniferous. In Meiling deposit, the types of fluid inclusions are mainly gas-liquid two-phase inclusions, the individual is smaller, the gas-liquid inclusions are smaller, the homogenization temperature of fluid inclusions is 117 ~ 238 擄C, and the salinity is 2.4C / 9.3, which is medium-low temperature and medium-low salinity fluids. The ore-forming pressure is 6.8 ~ 60.6 MPA, and the ore-forming depth is about 0.2 ~ 2.0 km 路m ~ (-1). The gas composition of fluid inclusions is mainly composed of H _ S _ 2O and the ore-forming fluids belong to H _ S _ 2O -NaCl system. The 未 ~ (18) O _ (H _ 2O) of ore-forming fluid is -5.75 鈥，

本文編號：2100144