(1. 中南大學 地球科學與信息物理學院，長沙 410083；
2. 江蘇省有色金屬華東地質(zhì)勘查局, 南京 210007；
3. 南京大學 地球科學與工程學院, 南京 210008)
摘 要: 安徽省池州市馬頭銅鉬礦區(qū)燕山期花崗閃長斑巖在距地表400 m以下，被眾多細粒鉀長花崗巖脈穿插，其熱液蝕變-礦化從上往下可分為上部石英-絹云母化帶、中部線型鉀長石化帶以及下部面型鉀長石化帶。典型的細脈-浸染狀銅鉬礦化主要發(fā)育于面型鉀長石化帶中，但鉀長花崗巖中也常見銅鉬硫化物的細脈和浸染。花崗閃長斑巖中石英脈流體包裹體均一溫度為101.4~437.8 ℃，并集中于150~300 ℃；鹽度(NaClequiv，質(zhì)量分數(shù))多數(shù)為0~12%。輝鉬礦和黃鐵礦δ34S變化范圍為1.2×10-3~9×10-3，平均值為4.5×10-3。輝鉬礦的δ34S略大于黃鐵礦的，表示成礦流體已經(jīng)達到了同位素平衡。作為一個斑巖型礦床，馬頭礦區(qū)花崗閃長巖體下方可能存在一個較大的鉀長花崗巖體，為該銅鉬礦床的形成提供了金屬物源及成礦流體，而花崗閃長斑巖主要起了容礦圍巖的作用。
關鍵字: 銅鉬礦石；膠輝鉬礦；斑巖型銅鉬礦；江南深斷裂；馬頭；池州
（1. School of Geosciences and Info-Physics, Central South University, Changsha 410083, China;
2. East China Mineral Exploration and Development Bureau, Nanjing 210007, China;
3. Department of Earth Sciences, Nanjing University, Nanjing 210008, China）
Abstract:The Yanshanian granodiorite porphyry of the copper-molybdenum ore district at Matou of Chizhou City in Anhui Province is inserted by numerous fine-grained moyite dikes at depths more than 400 m below surface. Hydrothermal alteration and mineralization of the granodiorite porphyry, the major ore-host, can be divided into three zones: the upper quartz-sericitization zone, the middle linear K-feldspar zone, and the lower K-feldsparization zone. Ores of the veinlets-disseminations-type occur typically in this zone, although veinlets and disseminations of copper and molybdenum sulfides can also be found in moyite dikes. Homogenization temperatures of fluid inclusions in quartz veins in the granodiorite porphyry range from 101.4 to 437.8 ℃, with a majority being 150-300 ℃. Most of the salinity (NaClequiv, mass fraction) determinations distributed in the range of 0-12% (mass fraction). δ34S of molybdenite and pyrite vary in the range between 1.2×10-3 and 9×10-3, with an average of 4.5×10-3. Slightly higher δ34S values of molybdenite than those of pyrite indicate isotope equilibrium in the ore-forming fluids. As the source of the moyite dikes, a bigger moyite intrusion is suggested to occur below the granodiorite body in the deposit area. The deposit is of the porphyry type with metals and fluids came essentially from the moyite, whereas the granodiorite can only be regarded as a host rock.
Key words: copper-molybdenum ore; jordisite; porphyry-type copper-molybdenum ore; Jiangnan deep fault; Matou; Chizhou
