岩石学报  2018, Vol. 34 Issue (5): 1469-1483   PDF    
江南造山带黄金洞金矿床成矿机制:矿物形成环境与金成矿物理化学条件制约
孙思辰1 , 张良1 , 吴圣刚2 , 高磊2 , 彭劲松2 , 文亭3     
1. 中国地质大学地质过程与矿产资源国家重点实验室, 北京 100083;
2. 湖南黄金洞矿业有限责任公司, 岳阳 414507;
3. 湖南省有色地勘局二一四队, 株洲 412007
摘要:黄金洞超大型金矿床位于江南造山带中段,赋存于新元古界浅变质岩系中,受控于NNE-NE向长平断裂带,金资源储量达100吨。该矿床可由南至北分为金福、金塘、杨山庄和曲溪矿段,主要矿化类型有石英-硫化物脉型、构造角砾岩型和黄铁毒砂绢英岩型。金属矿物主要发育有自然金、毒砂、黄铁矿、黄铜矿、闪锌矿、方铅矿、磁黄铁矿等;非金属矿物有石英、绢云母、方解石和菱铁矿等,其中金主要以自然金与不可见金形式存在。根据野外与镜下观察,金成矿作用分为Ⅰ石英-金-毒砂-黄铁矿、Ⅱ石英-金-多金属硫化物-白钨矿和Ⅲ石英-辉锑矿-绿泥石3个阶段,前二者为主要成矿阶段。曲溪矿段Ⅱ阶段毒砂相对不发育、而磁黄铁矿和自然金显著发育,绿泥石主要发育于Ⅲ阶段中,与辉锑矿及闪锌矿共生。根据不同矿段各阶段毒砂与Ⅲ阶段绿泥石成分,计算其温度、lgf(S2)与lgf(O2),可见Ⅰ阶段成矿温度与硫逸度高于Ⅱ阶段:杨山庄矿段两阶段成矿温度分别为300~378℃、260~300℃,lgf(S2)分别为-11~-7.2、-11.9~-10.1;金塘两阶段成矿温度为240~311℃、245~298℃;金福Ⅱ阶段成矿温度上限为297℃;曲溪矿段成矿温度为268~368℃,Ⅱ阶段毒砂lgf(S2)与Ⅲ阶段绿泥石lgf(O2)分别为-13.2~-8.7、-50.9~-40.1。根据不同阶段矿物之间的相互关系及成矿温度与硫逸度演化特征,推断Ⅰ、Ⅱ成矿阶段伴随强烈的硫化作用,金以类质同象方式进入毒砂和黄铁矿中,形成不可见金;其中Ⅱ阶段由于成矿流体压力骤降,含金流体发生相分离作用,H2S等气体大量逃逸,导致成矿流体中硫含量骤降,加以硫化作用持续消耗流体中的硫,促进了含金络合物分解与自然金的沉淀。
关键词: 矿物温度计     成矿物化条件     成矿机制     黄金洞金矿床     江南造山带    
Metallogenic mechanism of the Huangjindong gold deposit, Jiangnan Orogenic Belt: Constraints from mineral formation environment and physicochemical conditions of metallogenesis.
SUN SiChen1, ZHANG Liang1, WU ShengGang2, GAO Lei2, PENG JinSong2, WEN Ting3     
1. State Key Laboratory of Geological Process and Mineral Resources, China University of Geosciences, Beijing 100083, China;
2. Hunan Huangjindong Mining Co. Ltd., Yueyang 414507, China;
3. The 214th Geological Brigade, Hunan Provincial Bureau of Non-ferrous Metal and Geological Exploration, Zhuzhou 412007, China
Abstract: The Huangjindong gold deposit is located in the middle part of Jiangnan Orogenic Belt, and is a large gold deposit with a gold reserve of 100t. It is hosted in the Neoproterozoic epimetamorphic terranes and controlled by NE-NNE trending Changping fault. The Huangjindong gold deposit comprises Jinfu, Jintang, Yangshanzhuang and Quxi ore blocks from south to north. The ores of the gold deposit are mainly composed of sulfide-quartz vein, quartz breccia and pyrite-arsenopyrite-sericite-quartz altered slate. Natural gold, arsenopyrite, pyrite, chalcopyrite, sphalerite and pyrrhotite are mainly metallic minerals. Non-metallic minerals contain quartz, calcite, siderite, and so on. The occurrences of gold include visible and invisible gold. It is considered that gold metallogenic stages could be divided into auriferous quartz-arsenopyrite-pyrite stage (Ⅰ), auriferous quartz-polymetallic sulfide-scheelite stage (Ⅱ), quartz-stibnite stage (Ⅲ) based on field and microscopic observation. The first two stages are the main metallogenic stage. Mineral assemblage of Quxi ore block is slightly different from that of other ore blocks. There are less arsenopyrite and more pyrrhotite with visible gold developing in quartz vein of stage Ⅱ. Chlorite is contemporaneous with sphalerite and stibnite in stage Ⅲ. Based on arsenopyrite thermometer and stage Ⅲ chlorite thermometer from each stage in different ore blocks, it is concluded that temperature of stages Ⅰ and Ⅱ in Yangshanzhuang ore block are 260~378℃, 240~300℃, while the lgf(S2) are -11~-7.2 and -11.9~-10.1, respectively. They are 215~311℃, 170~298℃ and -11~-7.2, -11.9~-10.1 in lgf(S2) in Jintang. The maximum temperature of stage Ⅱ in Jinfu is 297℃, and the mineralization temperature of Quxi is 268~368℃. lgf(S2) of Jinfu is about -13.2~-8.7, and the lgf(O2) is -50.9~-40.1 in Quxi. Based on the correlations between the minerals in different stages and the evolution characteristics of the ore-forming temperature and lgf(S2), it is referred that Au get into arsenopyrite of stages Ⅰ and Ⅱ through isomorphism with strong sulfidation to form the invisible gold. In the stage Ⅱ, a large amount of gas such as H2S escapes due to the phase separation of the gold-bearing fluid, which results from the sudden pressure drop of the ore-forming fluid. The escaping of gas leads to the reduction of the sulfur content in the ore-forming fluid and the sulfur content is expanded by sulfofication. They accelerate the decomposition of gold-bearing complex and precipitation of natural gold.
Key words: Mineral geothermometry     Physicochemical characters of mineralization     Metallogenic mechanism     Huangjindong gold deposit     Jiangnan Orogenic Belt    

江南造山带是我国重要多金属成矿带,发育有赋存于前寒武系浅变质岩系的金矿床250余个,金总储量超过1000余吨(Deng and Wang, 2016)。黄金洞金矿床位于该带中部的湘东北地区,受控于长寿的NE-NNE向长沙-平江断裂带,金资源储量达100t。前人已对黄金洞金矿床地质与地球化学特征(许德如等, 2017; 夏浩东等, 2017)、成矿物质来源与成矿时代(董国军等, 2008; Xu et al., 2017)等开展大量工作,但成矿物理化学条件与成矿机制研究略显滞后,一定程度上影响了对该矿床成因的深入认识。具体主要体现在:(1)不同学者流体包裹体显微测温结果差别较大,且已有成果尚未精确限定成矿温度条件与演化。例如,叶传庆等(1988)测得少量原生包裹体均一温度为215~240℃;李杰等(2011)得出H2O-CO2三相包裹体的完全均一温度在336~339℃,可作为成矿温度下限;夏浩东等(2017)认为黄金洞石英流体包裹体主要为气液两相,流体温度在170~250℃;刘育等(2017)将成矿划分为三阶段,与金矿化相关的Ⅰ、Ⅱ阶段成矿温度集中于240~320℃;叶传庆等(1988)使用载金矿物黄铁矿、毒砂爆裂测温法获得主成矿温度在160~240℃;刘英俊(1993)通过毒砂温度计、毒砂爆裂法并结合流体包裹体均一温度对成矿温度限定为280~397℃。(2)前人多数通过流体包裹体研究来确定成矿机制,而由于未明确划分金成矿阶段、未获得原生流体包裹体岩相学证据,加以次生流体的发育,尚未获取令人信服的成矿物化条件,导致成矿机制争议较大。例如,李杰等(2011)认为深部热液与浅部地下水混合导致矿液的冷却、氧化和稀释,是黄金洞金矿床金沉淀的有效机制;刘英俊(1993)认为成矿流体进入断裂带中的扩容地段压力显著降低和氧逸度的升高,致使金发生沉淀;刘育等(2017)研究显示该矿床的主导成矿机制为成矿流体与围岩的交代反应引起相分离,液相CO2含量降低,引起Au(HS)2-溶解度降低,导致金发生沉淀。

成矿物化条件精确限定有助于厘定矿床成矿机制(Deng et al., 2009, 2015a; Yang et al., 2017a; Shu et al., 2013, 2017)。毒砂和黄铁矿等金属硫化物作为热液脉状金矿床中重要的载金矿物(Deng et al., 2017a; Zhang et al., 2017),其成分、结构、地球化学等特征蕴含了金成矿物理化学条件等重要信息(Kerr et al., 1999; Corkhill and Vaughan, 2009; Yang et al., 2016a; 张良等, 2014)。目前毒砂主量元素组成与形成物理化学条件的对应关系研究相对成熟,并在此基础上建立了毒砂矿物温度计(Kretschmar and Scott, 1976; Sharp et al., 1985)。同理,作为常见的伴生脉石矿物,绿泥石等矿物温度计也已建立(Cathelineau and Nieva, 1985; Kranidiotis and MacLean, 1987)。随着微区原位实验技术的不断发展,矿物主微量元素测试精度逐步提高(Li et al., 2014; Zhang et al., 2014; Deng et al., 2015b, c, 2018; Yang et al., 2016b, d, 2017b; Qiu et al., 2016, 2018),为毒砂和绿泥石等矿物温度计在矿床学中的应用提供了技术保障;得益于此,矿物温度计在限定金矿床成矿物理化学条件方面得以广泛应用(Chinnasamy et al., 2015; Dora and Randive, 2015),是对成矿流体包裹体测温等方法手段(Yang et al., 2008, 2016c; Qiu et al., 2017)的有益补充。因此,本文拟通过对黄金洞金矿床成矿阶段精确划分与不同阶段毒砂与绿泥石主、微量成分的测定,利用毒砂与绿泥石矿物形成物理化学条件精细限定成矿温度、硫逸度与氧逸度演化过程,探讨金成矿机制。

1 区域与矿床地质 1.1 区域地质

江南造山带呈反“S”状弧形展布于扬子板块与华夏板块之间(图 1Charvet et al., 1996),其主体结构形成于新元古代造山作用,造山过程具有多岛弧拼贴、多缝合的特点(薛怀民等, 2010),后期经历构造破坏与叠加复合等长期演化,是新元古代与晚中生代最为显著的铜-金成矿带(Deng et al., 2017b)。

图 1 湘东北区域地质图(据Xu et al., 2017修编) 1-第四系-白垩系;2-三叠系-泥盆系;3-志留系-震旦系;4-新元古界板溪群;5-新元古界冷家溪群;6-燕山期花岗岩;7-印支期花岗岩;8-加里东期花岗岩;9-新元古界花岗岩;10-深大断裂/次级断裂;11-韧性剪切带;12-向斜/背斜;13-倒转向斜/倒转背斜;14-金矿床(点)/铜铅锌金多金属矿床。Ⅰ-汨罗断陷盆地;Ⅱ-幕阜山-望湘断隆;Ⅲ-长沙-平江断陷盆地;Ⅳ-浏阳-衡东断隆;Ⅴ-醴陵-攸县断陷盆地;(A)九岭-清水韧性剪切带;(B)连云山-长沙韧性剪切带;(C)青草-株州韧性剪切带 Fig. 1 Regional geological map of northeastern Hunan Province (modified after Xu et al., 2017)

湘东北地区位于江南造山带中段,是我国重要的金-铅-锌-铜-钴多金属矿集区,金矿床与金矿化点约50个,控制黄金储量超300t(图 1许德如等, 2015; Xu et al., 2017)。区内主要出露有新元古界浅变质沉积岩,其是该区金矿床主要的赋矿围岩(贾宝华和彭和求, 2005);此外,区内局部出露震旦系页岩、二叠系灰岩和白垩系红层。长沙-平江、新宁-灰汤、浏阳-醴陵三条NE-NNE向深大走滑断裂等,共同构成盆岭相间构造格架。金和多金属矿床主要位于盆-岭转换带部位深大断裂的次级断裂和裂隙系统内,形成NNE向成岩成矿带(Deng et al., 2017c)。湘东北地区岩浆作用具有多期发育特征,晋宁期、加里东期、海西-印支期和燕山期岩浆岩在区内广泛发育。区内各期次岩浆岩与金矿床(体)没有明显空间关系。

1.2 矿床地质

黄金洞金矿床位于长平断裂带下盘,可分为杨山庄、金塘、金福和曲溪等金矿段(图 2)。矿区内主要发育有新元古界冷家溪群厚层状绢云母板岩、粉砂质板岩和条带状板岩。矿床内发育有一系列EW-NWW向N倾倒转褶皱与多条近平行的NW-近EW向层间压性断裂和切层断裂,断裂破碎带在空间内成群平行展布,由石英细脉和蚀变碎裂板岩组成,产状与含矿破碎带一致,多数N倾,倾角40°~75°;少数倾向S倾,倾角60°~75°。少量发育NE向断裂,发育位置临近区域性断裂-长平断裂,且断裂分布具有成群发育特征。

图 2 黄金洞金矿床地质图(据罗献林, 1988; 李杰等, 2011修编) Fig. 2 Geological map of the Huangjindong gold deposit (modified after Luo, 1988; Li et al., 2011)

杨山庄、金塘与金福等矿段位于矿床南部,EW向与NWW向断裂是主要的容矿构造。矿体呈脉状、透镜状及不规则状,均为EW-NWW向大致平行的矿脉,矿体倾角40°~60°,多数N倾,沿倾向延伸达33~1242m,厚度变化较大,0.25~16.6m,具严格断裂控矿特征。

曲溪矿段位于矿床北部,临近长平断裂带。矿段内近EW向轴迹的小型褶皱分布广泛;断层产状与其它矿段略有差异,主要有NE、NW及EW向3组。曲溪矿段已发现14条矿脉,其主体走向为NE向,倾向SE;少数矿脉为近EW向与SN向。

矿床内发育强烈的硅化、黄铁矿化、毒砂化、方铅矿化、闪锌矿化与绢云母化蚀变,还可见碳酸盐化、绿泥石化等,矿化、蚀变具有很强的分带性。黄铁矿化、毒砂化与金矿化密切相关,强蚀变区域多为矿床内主要的矿化地段。

2 金矿石矿物学特征 2.1 矿物组合与成矿阶段划分

黄金洞金矿床主要发育石英-硫化物脉型(图 3a, d)、黄铁毒砂绢英岩型(图 3b, e)和构造角砾岩型(图 3c, f)矿石。金属矿物主要发育有自然金、毒砂、黄铁矿、黄铜矿、闪锌矿、方铅矿、磁黄铁矿、车轮矿、白钨矿和辉锑矿;非金属矿物有石英、绢云母、方解石和菱铁矿等。其中金主要以自然金与不可见金形式存在,自然金主要赋存于板岩碎块与石英脉接触处的裂隙中,毒砂、黄铁矿、黄铜矿颗粒间隙中,毒砂-(黄铜矿)-黄铁矿连生体中,毒砂、黄铁矿组成的条带中,被包裹于车轮矿矿物中。不可见金以晶格金形式赋存于毒砂和含砷黄铁矿中(刘英俊等, 1989; 张文兰等, 1997)。

图 3 黄金洞金矿床矿石类型 (a、d)石英-硫化物型矿石;(b、e)黄铁毒砂绢英岩型;(c、f)石英角砾岩型 Fig. 3 Mineralization styles in the Huangjindong gold deposit (a, d) quartz-sulfid vein; (b, e) pyrite-arsenopyrit-sericit-quartz altered slate; (c, f) quartz breccia

根据野外与显微镜下观察矿物相互关系,黄金洞金矿床成矿作用可大致分为以下几个阶段(图 4):Ⅰ石英-金-毒砂-黄铁矿,主要矿物有乳白色石英、浸染状分布不等粒他形毒砂、少量自形的细粒黄铁矿,该阶段金主要以不可见金赋存于毒砂中;Ⅱ石英-金-多金属硫化物-白钨矿,发育烟灰色石英,可见明金与毒砂、黄铁矿、黄铜矿、闪锌矿、方铅矿、白钨矿,自然金主要赋存于烟灰色石英内(图 5a),毒砂也是不可见金主要的载金矿物;Ⅲ石英-绿泥石-辉锑矿,石英-绿泥石以脉状产出,与围岩接触部位,在围岩中发育有少量的辉锑矿与闪锌矿;Ⅳ石英-方解石/菱铁矿-绿泥石。曲溪矿段矿物组合相比于其它矿段略有差异,毒砂少量发育,仅在Ⅱ阶段可见于石英脉中;Ⅱ阶段内,磁黄铁矿显著发育,明金的含量相对较高;Ⅲ阶段中绿泥石较发育,与辉锑矿、闪锌矿共生。

图 4 黄金洞金矿床矿物生成顺序图 Fig. 4 Paragenetic assemblage and sequence of mineral in the Huangjindong gold deposit

图 5 黄金洞金矿床矿石手标本及镜下特征 (a) Ⅱ阶段含明金石英硫化物脉矿石;(b)金福矿段Ⅰ阶段不规则状毒砂;(c)杨山庄矿段Ⅱ阶段浸染状毒砂;(d)金塘矿段Ⅱ阶段毒砂交代Ⅰ阶段毒砂,点位为电子探针测试点;(e)曲溪矿段Ⅱ阶段毒砂与多金属硫化物,磁环铁矿发育;(f)自然金、方铅矿共生与热液白云母;(g)曲溪矿段Ⅲ阶段绿泥石脉;(h)绿泥石脉与围岩接触边界,靠近围岩一侧发育闪锌矿与辉锑矿;(i)曲溪矿段Ⅲ阶段绿泥石与白云母共生. Aspy-Ⅰ-Ⅰ阶段毒砂;Aspy-Ⅱ-Ⅱ阶段毒砂;Gn-方铅矿;Po-磁黄铁矿;Sp-闪锌矿;Snt-辉锑矿;Chl-绿泥石;Ms-白云母;Qtz-Ⅱ-Ⅱ阶段石英;Qtz-石英 Fig. 5 Photographs and photomicrographs of ore samples from the Huangjindong gold deposit (a) Ⅱ stage auriferous quartz-sulfide vein ore rock; (b) irregular arsenopyrite of Ⅰ stage from Jinfu ore block; (c) disseminated arsenopyrite of Ⅱ stage from Yangshanzhuang ore block; (d) Ⅱ stage arsenopyrite replace the Ⅰ stage arsenopyrite from Jintang ore block; (e) arsenopyrite, pyrrhotite and polymetallic sulfides from Ⅱ stage of Quxi ore block; (f) native gold symbioses with galena and hydrothermal sericite; (g) chlorite vein from Ⅲ stage of Quxi ore block; (h) The chlorite vein and sphalite and stibnite in the contact boundary of host rock develop; (i) chlorite is contemporary with muscovite from Ⅲ stage Quxi ore block. Aspy-Ⅰ-arsenopyrite in Ⅰ stage; Aspy-Ⅱ-arsenopyrite in Ⅱ stage; Gn-galena; Po-pyrrhotite; Sp-sphalerite; Snt-stibnite; Chl-chlorite; Ms-muscovite; Qtz-Ⅰ-quartz in Ⅰ stage; Qtz-quartz
2.2 毒砂和绿泥石矿物学特征

由于毒砂和绿泥石分别为黄金洞金矿床重要的载金矿物和伴生硅酸盐矿物,研究其形成物化条件前,有必要对各阶段矿物晶型、粒度、变形特征与产状等特征加以分析。

2.2.1 毒砂

毒砂作为金矿床中分布最广的硫化物,在黄金洞金矿床石英脉与近矿蚀变围岩中均有产出,在杨山庄、金塘、金福矿段主成矿Ⅰ、Ⅱ阶段中均有大量发育,在曲溪矿段Ⅱ阶段也有毒砂少量发育。根据镜下观察矿物生成次序与毒砂特征,Ⅰ阶段毒砂具浸染状,半自形-自形,不规则状,少量呈粒状,大小不等,约为50~200μm的特征;毒砂相互交错,受后期构造影响,往往发生破碎(图 5b);杨山庄、金塘、金福矿段Ⅱ阶段中毒砂,也呈浸染状分布,晶型较为完整,针状、短柱状、粒状,他形,粒径约200μm(图 5c)。Ⅱ阶段毒砂在局部交代Ⅰ阶段毒砂,形成类似于球状结构,分布于蚀变板岩中,早形成的Ⅰ阶段毒砂呈放射状,晶棱清晰可见,形成多边形孔隙,为Ⅱ阶段黄铁矿、闪锌矿与黄铜矿等多金属硫化物提供成矿空间(图 5d)。Ⅱ阶段毒砂交代Ⅰ阶段毒砂,不规则状,他形。曲溪矿段毒砂含量明显减少,零星发育,形状不规则,他形-半自形,较为破碎,主要为Ⅱ阶段产物(图 5e)。

毒砂是黄金洞金矿床最为重要的载金矿物,具有富S贫As化学特征。金主要是以类质同象存在于毒砂中,形成晶格金(张文兰等, 1997)。毒砂中金分布均匀,不随粒度具有明显变化(刘英俊等, 1989)。不同世代、不同产状毒砂,均有金的富集。

2.2.2 绿泥石

通过细致的显微镜下鉴定,绿泥石主要发育在曲溪矿段Ⅲ阶段,见细小热液绢云母与绿泥石具共生关系;绿泥石以鳞片状、片状、蠕虫状结构,不规则分布。整体具有脉状产出特征,与少量毒砂、闪锌矿、辉锑矿等矿物共生,被认为是成矿期的低温产物。

在杨山庄、金塘与金福矿段Ⅲ阶段仅发育少量绿泥石,与石英、方解石、菱铁矿等脉石矿物以脉状分布。绿泥石在正交偏光下呈靛蓝色,不规则状分布。

3 分析方法与结果 3.1 样品选择与测试分析方法

本次对黄金洞金矿床杨山庄、金塘、金福和曲溪矿段共8件矿石样品进行电子探针分析,样品涵盖了不同成矿阶段的毒砂和绿泥石,能够用于进一步揭示该矿床成矿温度的演化过程。

电子探针分析实验在中国地质科学院矿产资源研究所的国土资源部成矿作用与资源评价重点实验室完成,仪器型号为JXA-8230。硅酸盐矿物分析条件为加速电压15kV、电流20nA、束斑直径5μm;金属硫化物分析条件为加速电压20kV、电流20nA、束斑直径1~5μm。本次实验共计测试毒砂和绿泥石45点,其中包括杨山庄、金塘与金福矿段毒砂共计31点;曲溪矿段毒砂4点,绿泥石10点。

3.2 分析结果

杨山庄、金塘与金福矿段Ⅰ阶段中毒砂,共测试14个点,As原子百分数为29.20%~31.38%,平均值29.80%。上述三个矿段Ⅱ阶段毒砂,共测试14个点,As原子百分数为28.08%~29.10%,平均值28.68%;曲溪矿段Ⅱ阶段毒砂,共测试4个点,As原子百分数均大于30%,为30.31%~31.06%,平均值为30.51%(图 6a),明显大于其它矿段毒砂中As含量(表 1)。

图 6 黄金洞金矿床不同矿段毒砂化学成分 (a) As分布情况; (b) As与S原子百分数关系图解 Fig. 6 Composition variation of arsenopyrite in the Huangjindong gold deposi (a) distribution of As content of arsenopyrite; (b) relationship between As and S atomic percentages

表 1 黄金洞金矿床毒砂主量元素组成(wt%) Table 1 Geochemical composition of arsenopyrite of the Huangjindong gold deposit (wt%)

黄金洞金矿床不同矿段Ⅰ阶段毒砂As含量均略高于Ⅱ阶段。JT16D59B2毒砂集合体边部Ⅰ阶段毒砂As含量明显高于内部Ⅱ阶段毒砂(图 5d),分别为29.20%~30.06%、28.08%~28.50%,进一步说明早阶段形成的毒砂中As含量高于晚阶段的毒砂。

黄金洞金矿床所有毒砂As原子百分数与S原子百分数具有明显负相关性,说明该矿床中As对S发生取代进入毒砂中(图 6b)。

曲溪矿段绿泥石化学成分具有如下特征:SiO2含量为23.60%~24.37%,平均值23.99%;Al2O3为22.18%~22.82%,平均值为22.52%;FeO为31.50%~33.53%;平均值为32.64%;MgO为9.63%~10.44%,平均值为10.16%;MnO为0.15%~0.28%,平均值为0.21%。所用绿泥石点的Na2O+K2O+CaO明显低于0.5%(表 2),说明绿泥石未受到后期改造(Foster, 1962),可以进行矿物温度测温计算(Vidal et al., 2001)。

表 2 黄金洞金矿床曲溪矿段绿泥石主量元素组成(wt%) Table 2 Geochemical composition of chlorite of Quxi ore block in Huangjindong gold deposit (wt%)
4 讨论 4.1 矿物形成环境与金成矿物理化学条件 4.1.1 毒砂形成环境

Kretschmar and Scott (1976)提出矿物共生组合与毒砂中Fe、S、As含量可限定其形成温度。经过数十年的研究积累,毒砂温度计已可广泛应用不同形成环境的热液矿床中(Stanley and Vaughan, 1982; Kerr et al., 1999; Deng et al., 2015c)。黄金洞金矿床杨山庄、金塘、金福矿段Ⅰ、Ⅱ阶段毒砂为不可见金的主要载体,矿石具有稳定矿物共生组合(毒砂+黄铁矿);曲溪Ⅱ阶段毒砂与明金、黄铁矿、磁黄铁矿共生, 根据不同矿段各阶段矿物共生组合关系将毒砂As原子百分数投于lg f(S2)-温度(T)关系图解(Kretschmar and Scott, 1976; Sharp et al., 1985)中,以获取毒砂形成环境信息。

杨山庄、金塘Ⅰ阶段毒砂形成温度普遍高于300℃,为298~378℃;Ⅱ阶段毒砂温度较低为260~300℃,两矿段毒砂温度分别为296±4℃、279±19℃;曲溪矿段Ⅱ阶段毒砂温度较高为333±35℃。杨山庄矿段Ⅰ阶段lg f(S2)为-11.0~-7.2,Ⅱ阶段lg f(S2)降低为-11.9~-10.1;金塘矿段Ⅰ阶段、Ⅱ阶段lg f(S2)分别为-11.5~-8.9与-14~-10.6;金福矿段Ⅱ阶段与曲溪矿段Ⅱ阶段lg f(S2)分别为-13.6~-10.5与-13.2~-8.7。可见,黄金洞金矿床硫逸度具有Ⅱ阶段硫逸度略低于Ⅰ阶段硫逸度的特征。毒砂集合体(图 5d),外部温度约为304~330℃,内部毒砂颗粒,由于As原子含量过低,超出毒砂稳定区范围(图 7),温度过低,进一步说明两阶段毒砂形成温度具有差异。

图 7 毒砂稳定区域lg f(S2)-温度(T)关系图解(据Kretschmar and Scott, 1976; Sharp et al., 1985) (a)杨山庄矿段Ⅰ、Ⅱ阶段与金福矿段Ⅰ阶段毒砂形成温度;(b)金塘矿段Ⅰ、Ⅱ阶段与曲溪矿段Ⅱ阶段毒砂形成温度 Fig. 7 Activity of lg f(S2) temperature (T) projection of the stability field of arsenopyrite (after Kretschmar and Scott, 1976; Sharp et al., 1985) (a) arsenopyrite thermometer of Ⅰ, Ⅱ stage from Yangshanzhuang and Ⅱ stage from Jinfu; (b) arsenopyrite thermometer of Ⅰ, Ⅱ stage from Jintang and Ⅱ stage from Quxi
4.1.2 绿泥石形成环境

绿泥石是在各类岩石与不同地质环境中广泛分布,是金成矿过程中重要的伴生矿物之一。其化学式为(RX2+Ry3+6-x-y)6(SizR4-z3+)4O10(OH)8,其中R2+代表二价阳离子,如Fe2+、Mg2+;R3+代表三价阳离子,如Al3+、Fe3+;□代表八面体空位。其化学成分受控于二价离子Fe2+与Mg2+之间替换、契尔马克AlAl与Si(Mg, Fe2+)替换、二八面体与三八面体3(Mg, Fe2+)与□2Al替换。其化学成分的变化是由于形成环境复杂多变所导致的,通过研究绿泥石化学成分,能够揭示绿泥石形成的物化条件(Vidal et al., 2001; Shu and Lai, 2017)。

根据绿泥石中Si、Fe、Mg和Mn成分含量的差异,对绿泥石进行分类。分类依据使用Hey (1954)的Si-Fe/(Fe+Mg)图作为绿泥石分类底图(图 8a)。绿泥石Si为2.50~2.60,Fe/(Fe+Mg)比值在0.631~0.661。所有点均落在铁绿泥石区域。对Si-Fe/(Fe+Mg+Mn)投图(图 8b),所有点均落Fe/(Fe+Mg+Mn)等于0.5的上半部分,证明曲溪矿段Ⅲ阶段绿泥石为富铁型,该类型绿泥石常伴生于金矿床中(Dora and Randive, 2015)。

图 8 曲溪矿段绿泥石矿物成分 (a)曲溪矿段绿泥石命名与分类(Hey, 1954);(b)铁-镁绿泥石分类方案(Bayliss, 1975) Fig. 8 Mineral composition of chlorite from Quxi ore block (a) nomenclature and classification of chlorite (Hey, 1954); (b) classification of Fe- and Mg-chlorite (Bayliss, 1975)

Al/Al的比值可以指示绿泥石的四面体结构中的离子置换是发生钙镁闪石型置换还是Fe-Mg离子的置换(Xie et al., 1997)。曲溪矿段绿泥石中的Al/Al的比值分布较为平均,有6个点Al/Al略小于1(图 9a),说明矿段中绿泥石Al对四面体中Si的置换数量少于Al对八面体中Mg2+的置换数量。4个点略大于1,则说明八面体内发生的Al-Mg置换强于Al对Si的置换。

图 9 曲溪矿段绿泥石成分变化图解 (a) Al与Al的比值;(b-d)镁与其它主要金属离子之间的关系 Fig. 9 Variation diagram of chlorite showing compositional variations from Quxi ore block (a) Al vs. Al; (b-d) Mg vs. other main metal cations

一次变质作用形成的绿泥石中的Mg与其它主要阳离子呈现良好的线性关系(Xie et al., 1997)。曲溪金矿床绿泥石Mg与Si、Al+Fe与Fe之间,并不存在明显的线性关系,点分布较为混乱(图 9b-d)。说明曲溪矿段绿泥石在形成之后,又经历了多期次的变质作用,但绿泥石结构并未改变。在Si-Fe/(Fe+Mg+Mn)图解中显示该矿段绿泥石主要为富含铁元素(图 8b),但是Mg与Fe相关性图解反映绿泥石可分为相对富铁与相对富镁两部分(图 9d),且相对富镁绿泥石含量更多。

前人通过XRD的研究,发现绿泥石的d001底面间距与其结晶温度也具有良好的相关性(Battaglia, 1999),后经过计算与修正,可将电子探针数据转化为d001并对绿泥石结晶温度进行计算,底面间距与绿泥石形成温度具有良好的拟合度(r=0.95)(Rausell-Colom et al., 1991; Nieto, 1997)。通过上述方法计算绿泥石形成温度为256~268℃,平均为263℃(表 2)。

Walshe (1986)研究绿泥石形成过程中结构变化的多型方法,创建6组分绿泥石固溶体模型,将绿泥石分为6个热力学端元,不仅能够计算绿泥石形成温度,还可以通过不同的矿物组合,建立不同的反应方程式,运用活度系数ai与化学方程平衡系数Kj计算绿泥石形成时的lg f(O2)、lg f(S2)。郑作平等(1997)运用Walshe (1986)提出的热力学端元分别对八卦庙金矿床绿泥石lg f(S2)与lg f(O2)进行分析,得到良好的效果。

曲溪矿段Ⅲ阶段绿泥石与石英、极少量毒砂与黄铁矿共生且未见磁黄铁矿等含铁硫化物,因此若运用绿泥石来计算lg f(S2)会使结果偏大。但绿泥石lg f(O2)表现较为稳定,根据Walshe (1986)所提出的C3与C6热力学端元的反应方程式,可进行绿泥石lg f(O2)的计算,即:

(1)

郑作平等(1997)总结绿泥石C3端元与C6端元反应获得lg f(O2)计算公式:

(2)

公式(2)中K1代表(1)化学反应方程式平衡常数,可根据张伟等(2014)用数学方法归纳Walshe (1986)不同温度所对应的lgK1,重新拟合平衡常数与温度的函数关系,即:

(3)

公式(3)中的e为自然底数、t为温度。将所测得的绿泥石温度,代入公式(3),并计算公式(2),即可求出绿泥石形成时的氧逸度。结果(表 2)显示lg f(O2)介于-50.9~-40.1,平均值为-44.57。

综上,曲溪矿段Ⅲ阶段绿泥石主要为铁绿泥石,由于Mg2+与其它主要阳离子含量不具有明显的线性关系,可推测在曲溪矿段绿泥石形成之后,经历了一定变质作用的影响。利用绿泥石底面间距计算绿泥石成矿温度为257~268℃,C3端元与C6端元反应计算绿泥石lg f(O2)为-50.9~-40.1。

4.1.3 金成矿物理化学条件

不同阶段毒砂与绿泥石形成温度与前人流体包裹体数据(表 3)结合,可以精细限定黄金洞金矿床不同成矿阶段物理化学条件与演化。该矿床Ⅰ阶段成矿温度与硫逸度高于Ⅱ阶段(图 10):毒砂温度计结果指示杨山庄Ⅰ阶段不可见金形成初始温度约为378℃。流体包裹体均一温度被认为是成矿温度下限(李杰等, 2011; 刘育等, 2017),且测试数据往往受次生包裹体影响,温度低于真实成矿温度;因此根据毒砂形成温度与流体包裹体均一温度(表 3),将该矿段Ⅰ、Ⅱ阶段成矿温度分别限定在300~378℃与260~300℃;岩相学观察与电子探针结果(表 1)结果指示,成矿Ⅰ、Ⅱ阶段均有不可见金产出,而自然金主要发育于Ⅱ阶段260~290℃温度条件下;此阶段lg f(S2)由-11~-7.2降至-11.9~-10.1。金塘矿段Ⅱ阶段成矿温度较Ⅰ阶段小幅降低,Ⅰ、Ⅱ阶段分别为240~311℃、245~298℃,自然金沉淀温度区间为245~260℃,两阶段lg f(S2)分别为-11.5~-8.9、-14~-10.6;金福矿段Ⅱ阶段成矿温度上限由毒砂形成温度限定,约为297℃,lg f(S2)约-13.6~-10.5;曲溪矿段金成矿温度由Ⅱ阶段毒砂与Ⅲ阶段绿泥石限定,为268~368℃,lg f(S2)跨度较大,为-13.2~-8.7。在流体演化过程中,成矿体系lg f(O2)由-36~-30逐渐降低至-50~-40(表 3),趋于还原环境。

表 3 黄金洞金矿床各矿段成矿物理化学条件 Table 3 Mineralization conditions of the ore blocks in Huangjindong gold deposit

图 10 杨山庄、金塘、金福矿段不同成矿阶段成矿温度 数据来源于罗献林, 1988; 叶传庆等, 1988; Liu et al., 1993; 刘育等, 2017; 夏浩东等, 2017以及本文矿物温度计数据 Fig. 10 Relationship between gold mineralization stages and temperature of the Yangshanzhuang, Jintang and Jinfu ore blocks Data from Luo, 1988; Ye et al., 1988; Liu et al., 1993; Liu et al., 2017; Xia et al., 2017 and mineralogic thermometer of this paper
4.2 金成矿机制

黄金洞金矿床中金主要以不可见金与自然金的形式赋存;其中,电子探针分析与前人研究成果(刘英俊等, 1989; 张文兰等, 1997)表明,不可见金主要赋存于Ⅰ、Ⅱ成矿阶段的毒砂与黄铁矿中。成矿Ⅰ阶段,温度为300~378℃、pH约为6~7、lg f(O2)为-36~-30;该条件下金主要以Au(HS)2-1的形式运移(Phillips and Powell, 2010);此阶段硫逸度相对较高。伴随着强烈的硫化作用,毒砂与黄铁矿等硫化物沉淀。电子探针数据显示该阶段载金毒砂中As与S呈负相关关系(图 6b),表明As3-取代了S2-进入毒砂晶体(Velásquez et al., 2014)。伴随着过量的As进入毒砂中,为保持电价平衡,Au3+取代毒砂中的Fe2+,形成晶格金(Arehart et al., 1993)。Ⅱ阶段成矿流体温度与硫逸度降低,由于Au和As元素具有相似的化学性质,因此金能以Au-As类质同象进入毒砂中(刘英俊等, 1989),于毒砂中形成了大量的不可见金。虽然上述过程中流体温度下降,但是大量研究表明温度的降低在热液脉型金矿中并不是金高效沉淀的主控因素(Goldfarb and Groves, 2015)。除温度降低外,成矿Ⅱ阶段硫逸度明显降低,表明流体中的S含量明显下降;该阶段中大量的自然金沉淀表明含金络合物大量分解。然而黄金洞金矿床矿体中硫化物含量普遍小于5%,硫化作用本身不足以导致含金络合物急剧分解、硫含量骤降与硫逸度的明显降低。结合世界范围内热液脉状矿床大量成矿流体研究(Deng et al., 2009; Wang et al., 2015; Yang et al., 2016e),推断流体沸腾作用诱发了含金流体相分离,进而导致了H2S迅速逃逸、含金硫络合物快速分解与自然金大量沉淀。黄金洞金矿床成矿Ⅱ阶段发生了强烈的角砾岩化作用(图 4c),伴随着Ⅰ阶段石英脉的角砾岩化,渗透率急剧提高,压力骤降。成矿流体压力的骤降可能是导致流体相分离的主要原因(Yang et al., 2016d, 2017b; Neyedley et al., 2017; 杨立强等, 2014)。黄金洞金矿床内,曲溪矿段毒砂相对较高的As含量,指示其成矿温度比其它矿段略高;相对发育的磁黄铁矿说明成矿流体相对较为还原(Morey et al., 2008);这可能是该矿段距离主控矿的长平断裂较近,流体运移路径短,水岩反应对流体的改造作用相对较弱的缘故,主导成矿机制与其它矿段并无差异。

5 结论

黄金洞金矿床金福、金塘、杨山庄与曲溪四个矿段金成矿作用主要分为:Ⅰ石英-金-毒砂-黄铁矿、Ⅱ石英-金-多金属硫化物-白钨矿和Ⅲ石英-辉锑矿-绿泥石三个阶段;前二者为主要成矿阶段。曲溪矿段Ⅱ阶段毒砂相对不发育;而磁黄铁矿与自然金显著发育;绿泥石主要发育于Ⅲ阶段中,与辉锑矿及闪锌矿共生。各矿段不同阶段毒砂与Ⅲ阶段绿泥石形成环境,指示该矿床成矿过程中成矿温度与硫逸度逐渐降低。根据成矿温度与硫逸度演化特征、矿石矿物组合、载金矿物含量与不同阶段金的赋存状态,推断成矿Ⅰ、Ⅱ阶段伴随强烈的硫化作用,金以类质同象方式进入毒砂和黄铁矿中,形成不可见金;其中Ⅱ阶段由于成矿流体压力骤降,含金流体发生相分离作用,H2S气体大量逃逸,导致成矿流体中硫含量骤降,加以硫化作用持续消耗流体中的硫,促进了含金络合物分解与自然金的沉淀。除距离主控断裂远近不同导致的金成矿物理化学条件略有差异外,各矿段主导成矿机制并无差异。

致谢 研究工作得到了中国地质大学(北京)邓军教授、杨立强教授、王中亮讲师、李楠讲师与邱昆峰讲师的指导和帮助;野外工作得到了黄金洞金矿床相关工作人员的帮助与支持;电子探针实验测试得到了中国地质科学院矿产资源研究所陈振宇研究员、陈郑辉教授级高工与刘浩硕士的帮助;硕士生于皓丞、王久懿与李荣华参与了部分研究工作;谨此致谢。
参考文献
Arehart GB, Chryssoulis SL and Kesler SE. 1993. Gold and arsenic in iron sulfides from sediment-hosted disseminated gold deposits:Implications for depositional processes. Economic Geology, 88(1): 171-185. DOI:10.2113/gsecongeo.88.1.171
Battaglia S. 1999. Applying x-ray geothermometer diffraction to a chlorite. Clays and Clay Minerals, 47(1): 54-63. DOI:10.1346/CCMN
Bayliss P. 1975. Nomenclature of the trioctahedral chlorites. Canadian Mineralogist, 13(2): 178-180.
Cathelineau M and Nieva D. 1985. A chlorite solid solution geothermometer the Los Azufres (Mexico) geothermal system. Contributions to Mineralogy and Petrology, 91(3): 235-244. DOI:10.1007/BF00413350
Charvet J, Shu LS, Shi YS, Guo LZ and Faure M. 1996. The building of South China:Collision of Yangzi and Cathaysia blocks, problems and tentative answers. Journal of Southeast Asian Earth Sciences, 13(3-5): 223-235. DOI:10.1016/0743-9547(96)00029-3
Chinnasamy SS, Uken R, Reinhardt J, Selby D and Johnson S. 2015. Pressure, temperature, and timing of mineralization of the sedimentary rock-hosted orogenic gold deposit at Klipwal, southeastern Kaapvaal Craton, South Africa. Mineralium Deposita, 50(6): 739-766. DOI:10.1007/s00126-014-0573-9
Corkhill CL and Vaughan DJ. 2009. Arsenopyrite oxidation:A review. Applied Geochemistry, 24(12): 2342-2361. DOI:10.1016/j.apgeochem.2009.09.008
Deng J, Yang LQ, Gao BF, Sun ZS, Guo CY, Wang QF and Wang JP. 2009. Fluid evolution and metallogenic dynamics during tectonic regime transition:Example from the Jiapigou gold belt in Northeast China. Resource Geology, 59(2): 140-152. DOI:10.1111/rge.2009.59.issue-2
Deng J, Liu XF, Wang QF and Pan RG. 2015a. Origin of the Jiaodong-type Xinli gold deposit, Jiaodong peninsula, China:Constraints from fluid inclusion and C-D-O-S-Sr isotope compositions. Ore Geology Reviews, 65(Pt 3): 674-686.
Deng J, Wang QF, Li GJ, Hou ZQ, Jiang CZ and Danyushevsky L. 2015b. Geology and genesis of the giant Beiya porphyry-skarn gold deposit, northwestern Yangtze Block, China. Ore Geology Reviews, 70: 457-485. DOI:10.1016/j.oregeorev.2015.02.015
Deng J, Wang CM, Bagas L, John E, Carranza EJM and Lu YJ. 2015c. Cretaceous-Cenozoic tectonic history of the Jiaojia fault and gold mineralization in the Jiaodong peninsula, China:Constraints from zircon U-Pb, illite K-Ar, and apatite fission track thermochronometry. Mineralium Deposita, 50(8): 987-1006. DOI:10.1007/s00126-015-0584-1
Deng J and Wang QF. 2016. Gold mineralization in China:Metallogenic provinces, deposit types and tectonic framework. Gondwana Research, 36: 219-274. DOI:10.1016/j.gr.2015.10.003
Deng J, Liu XF, Wang QF, Dilek Y and Liang YY. 2017a. Isotopic characterization and petrogenetic modeling of Early Cretaceous mafic diking:Lithospheric extension in the North China Craton, eastern Asia. GSA Bulletin, 129(11-12): 1379-1407. DOI:10.1130/B31609.1
Deng J, Wang QF and Li GJ. 2017b. Tectonic evolution, superimposed orogeny, and composite metallogenic system in China. Gondwana Research, 50: 216-266. DOI:10.1016/j.gr.2017.02.005
Deng J, Wang CM, Bagas L, Santosh M and Yao E. 2018. Crustal architecture and metallogenesis in the south-eastern North China Craton. Earth-Sciences Review. DOI:10.1016/j.earscirev.2018.05.001
Deng T, Xu DR, Chi GX, Wang ZL, Jiao QQ, Ning JT, Dong GJ and Zou FH. 2017c. Geology, geochronology, geochemistry and ore genesis of the Wangu gold deposit in northeastern Hunan Province, Jiangnan Orogen, South China. Ore Geology Reviews, 88: 619-637. DOI:10.1016/j.oregeorev.2017.01.012
Dong GJ, Xu DR, Wang L, Chen GH, He ZL, Fu GG, Wu J and Wang ZL. 2008. Determination of mineralizing ages on gold ore deposits in the eastern Hunan province, South China and isotopic tracking on ore-forming fluids:Re-discussing gold ore deposit type. Geotectonica et Metallogenia, 32(4): 482-491.
Dora ML and Randive KR. 2015. Chloritisation along the Thanewasna shear zone, western Bastar Craton, Central India:Its genetic linkage to Cu-Au mineralization. Ore Geology Reviews, 70: 151-172. DOI:10.1016/j.oregeorev.2015.03.018
Foster MD. 1962. Interpretation of the composition and a classification of the chlorites. US Geology Survey Professional Paper, 414A. Washington, DC: US Government Printing Office: A1-A33.
Goldfarb RJ and Groves DI. 2015. Orogenic gold:Common or evolving fluid and metal sources through time. Lithos, 233: 2-26. DOI:10.1016/j.lithos.2015.07.011
Hey MH. 1954. A new review of the chlorite. Mineralogical Magazine, 30(244): 277-292.
Jia BH and Peng HQ. 2005. Precambrian Geology and Mineralization in the Northeast Hunan Province. Beijing: Geological Publishing House.
Kerr LC, Craw D and Youngson JH. 1999. Arsenopyrite compositional variation over variable temperatures of mineralization, Otago Schist, New Zealand. Economic Geology, 94(1): 123-128. DOI:10.2113/gsecongeo.94.1.123
Kranidiotis P and MacLean WH. 1987. Systematics of chlorite alteration at the Phelps Dodge massive sulfide deposit, Matagami, Quebec. Economic Geology, 82(7): 1898-1911. DOI:10.2113/gsecongeo.82.7.1898
Kretschmar U and Scott SD. 1976. Phase relations involving arsenopyrite in the system Fe-As-S and their application. Canadian Mineralogist, 14(3): 364-386.
Li J, Chen BH, An JH, Tan SM, Zhang XG and Yao YJ. 2011. Characteristics of fluid inclusions of the Huangjindong gold deposit, Hunan Province. Geology and Mineral Resources of South China, 27(2): 163-168.
Li N, Deng J, Yang LQ, Goldfarb RJ, Zhang C, Marsh E, Lei SB, Koenig A and Lowers H. 2014. Paragenesis and geochemistry of ore minerals in the epizonal gold deposits of the Yangshan gold belt, West Qinling, China. Mineralium Deposita, 49(4): 427-449. DOI:10.1007/s00126-013-0498-8
Liu Y, Zhang L, Sun SC, Qi P, Wu SG and Gao L. 2017. Mineralization mechanism of Yangshanzhuang gold deposit, northeastern Hunan Province. Acta Petrologica Sinica, 33(7): 2273-2284.
Liu YJ, Sun CY, Cui WD and Ji JF. 1989. Study on the occurrence of gold in arsenopyrite of Huang-Jindong gold deposit in Hunan Province. Contributions to Geology and Mineral Resources Research, 4(1): 42-49.
Liu YJ. 1993. Jiangnan Gold Deposits and Their Metallogenic Geochemical Background. Nanjing: Nanjing University Press.
Liu YJ, Li Y, Qiu DT and Ji JF. 1993. Ore-controlled mechanism and geochemical characteristics of gold-bearing formation in Northwest Jiangxi terrain. Science in China (Series B), 36(10): 1263-1275.
Luo XL. 1988. On the genesis and metallogenic model of the Huangjindong gold deposit from Hunan. Journal of Guilin College of Geology, 8(3): 225-240.
Morey AA, Tomkins AG, Bierlein FP, Weinberg RF and Davidson GJ. 2008. Bimodal distribution of gold in pyrite and arsenopyrite:Examples from the Archean Boorara and Bardoc shear systems, Yilgarn Craton, western Australia. Economic Geology, 103(3): 599-614. DOI:10.2113/gsecongeo.103.3.599
Neyedley K, Hanley JJ, Fayek M and Kontak DJ. 2017. Textural, fluid inclusion, and stable oxygen isotope constraints on vein formation and gold precipitation at the 007 deposit, rice Lake Greenstone belt, Bissett, Manitoba, Canada. Economic Geology, 112(3): 629-660. DOI:10.2113/econgeo.112.3.629
Nieto F. 1997. Chemical composition of metapelitic chlorites:X-ray diffraction and optical property approach. European Journal of Mineralogy, 9(4): 829-842. DOI:10.1127/ejm/9/4/0829
Phillips GN and Powell R. 2010. Formation of gold deposits:A metamorphic devolatilization model. Journal of Metamorphic Geology, 28(6): 689-718. DOI:10.1111/(ISSN)1525-1314
Qiu KF, Taylor RD, Song YH, Yu HC, Song KR and Li N. 2016. Geologic and geochemical insights into the formation of the Taiyangshan porphyry copper-molybdenum deposit, Western Qinling Orogenic Belt, China. Gondwana Research, 35: 40-58. DOI:10.1016/j.gr.2016.03.014
Qiu KF, Marsh E, Yu HC, Pfaff K, Gulbransen C, Gou ZY and Li N. 2017. Fluid and metal sources of the Wenquan porphyry molybdenum deposit, Western Qinling, NW China. Ore Geology Reviews, 86: 459-473. DOI:10.1016/j.oregeorev.2017.02.035
Qiu KF, Yu HC, Gou ZY, Liang ZL, Zhang JL and Zhu R. 2018. Nature and origin of Triassic igneous activity in the Western Qinling Orogen:The Wenquan composite pluton example. International Geology Review, 60(2): 242-266. DOI:10.1080/00206814.2017.1334598
Rausell-Colom JA, Wiewiora A and Matesanz E. 1991. Relation between composition and d001 for chlorite. American Mineralogis, 76: 1373-1379.
Sharp ZD, Essene EJ and Kelly WC. 1985. A re-examination of the arsenopyrite geothermometer:Pressure considerations and applications to natural assemblages. Canadian Mineralogist, 23: 517-534.
Shu QH, Lai Y, Sun Y, Wang C and Meng S. 2013. Ore genesis and hydrothermal evolution of the Baiyinnuo'er zinc-lead skarn deposit, Northeast China:Evidence from isotopes (S, Pb) and fluid inclusions. Economic Geology, 108(4): 835-860. DOI:10.2113/econgeo.108.4.835
Shu QH, Chang ZS, Hammerli J, Lai Y and Huizenga JM. 2017. Composition and evolution of fluids forming the Baiyinnuo'er Zn-Pb skarn deposit, northeastern China:Insights from laser ablation ICP-MS study of fluid inclusions. Economic Geology, 112(6): 1441-1460. DOI:10.5382/econgeo.2017.4516
Shu QH and Lai Y. 2017. Fluid inclusion and oxygen isotope constraints on the origin and hydrothermal evolution of the Haisugou porphyry Mo deposit in the northern Xilamulun district, NE China. Geofluids, 2017: 4094582. DOI:10.1155/2017/4094582
Stanley CJ and Vaughan DJ. 1982. Copper, lead, zinc and cobalt mineralization in the English Lake District:Classification, conditions of formation and genesis. Journal of the Geological Society, 139(5): 569-579. DOI:10.1144/gsjgs.139.5.0569
Velásquez G, Béziat D, Salvi S, Siebenaller L, Borisova AY, Pokrovski GS and de Parseval P. 2014. Formation and deformation of pyrite and implications for gold mineralization in the El Callao district, Venezuela. Economic Geology, 109(2): 457-486. DOI:10.2113/econgeo.109.2.457
Vidal O, Parra T and Trotet F. 2001. A thermodynamic model for FE-MG aluminous chlorite using data from phase equilibrium experiments and natural pelitic assemblages in the 100 to 600℃, 1 to 25 kb range. American Journal of Science, 301(6): 557-592. DOI:10.2475/ajs.301.6.557
Walshe JL. 1986. A six-component chlorite solid solution model and the conditions of chlorite formation in hydrothermal and geothermal systems. Economic Geology, 81(3): 681-703. DOI:10.2113/gsecongeo.81.3.681
Wang ZL, Yang LQ, Guo LN, Marsh E, Wang JP, Liu Y, Zhang C, Li RH, Zhang L, Zheng XL and Zhao RX. 2015. Fluid immiscibility and gold deposition in the Xincheng deposit, Jiaodong Peninsula, China:A fluid inclusion study. Ore Geology Reviews, 65(Pt 3): 701-717.
Xia HD, Xi CZ, Deng HJ, Xiao X and Wu SG. 2017. Genesis of Huangjindong gold deposit:New evidence for sulfur, lead isotopes and fluid inclusions. Gold, 38(10): 19-24.
Xie XG, Byerly GR and Ferrell Jr RE. 1997. Iib trioctahedral chlorite from the Barberton greenstone belt:Crystal structure and rock composition constraints with implications to geothermometry. Contributions to Mineralogy and Petrology, 126(3): 275-291. DOI:10.1007/s004100050250
Xu DR, Dong GJ, Deng T, Ning JT, Wang ZL and Zou FH. 2015. Large-scale gold mineralization and geodynamic background in Northeast Hunan Province. Acta Mineralogica Sinica, 35(Suppl.1): 85.
Xu DR, Deng T, Chi GX, Wang ZL, Zou FH, Zhang JL and Zou SH. 2017. Gold mineralization in the Jiangnan Orogenic Belt of South China:Geological, geochemical and geochronological characteristics, ore deposit-type and geodynamic setting. Ore Geology Reviews, 88: 565-618. DOI:10.1016/j.oregeorev.2017.02.004
Xu DR, Zou FH, Ning JT, Deng T, Wang ZL, Chen GW, Zhang JL and Dong GJ. 2017. Discussion on geological and structural characteristics and associated metallogeny in northeastern Hunan Province, South China. Acta Petrologica Sinica, 33(3): 695-715.
Xue HM, Ma F, Song YQ and Xie YP. 2010. Geochronology and geochemisty of the Neoproterozoic granitoid association from eastern segment of the Jiangnan orogen, China:Constraints on the timing and process of amalgamation between the Yangtze and Cathaysia blocks. Acta Petrologica Sinica, 26(11): 3215-3244.
Yang LQ, Deng J, Zhang J, Guo CY, Gao BF, Gong QJ, Wang QF, Jiang SQ and Yu HJ. 2008. Decrepitation thermometry and compositions of fluid inclusions of the Damoqujia gold deposit, Jiaodong gold province, China:Implications for metallogeny and exploration. Journal of China University of Geosciences, 19(4): 378-390. DOI:10.1016/S1002-0705(08)60071-0
Yang LQ, Deng J, Wang ZL, Zhang L, Guo LN, Song MC and Zheng XL. 2014. Mesozoic gold metallogenic system of the Jiaodong gold province, eastern China. Acta Petrologica Sinica, 30(9): 2447-2467.
Yang LQ, Deng J, Li N, Zhang C, Ji XZ and Yu JY. 2016a. Isotopic characteristics of gold deposits in the Yangshan Gold Belt, West Qinling, central China:Implications for fluid and metal sources and ore genesis. Journal of Geochemical Exploration, 168: 103-118. DOI:10.1016/j.gexplo.2016.06.006
Yang LQ, Deng J, Wang ZL, Guo LN, Li RH, Groves DI, Danyushevsky LV, Zhang C, Zheng XL and Zhao H. 2016b. Relationships between gold and pyrite at the Xincheng gold deposit, Jiaodong Peninsula, China:Implications for gold source and deposition in a brittle epizonal environment. Economic Geology, 111(1): 105-126. DOI:10.2113/econgeo.111.1.105
Yang LQ, Deng J, Guo RP, Guo LN, Wang ZL, Chen BH and Wang XD. 2016c. World-class Xincheng gold deposit:An example from the giant Jiaodong Gold Province. Geoscience Frontiers, 7(3): 419-430. DOI:10.1016/j.gsf.2015.08.006
Yang LQ, Deng J, Dilek Y, Meng JY, Gao X, Santosh M, Wang D and Yan H. 2016d. Melt source and evolution of Ⅰ-type granitoids in the SE Tibetan Plateau:Late Cretaceous magmatism and mineralization driven by collision-induced transtensional tectonics. Lithos, 245: 258-273. DOI:10.1016/j.lithos.2015.10.005
Yang LQ, Deng J, Guo LN, Wang ZL, Li XZ and Li JL. 2016e. Origin and evolution of ore fluid, and gold-deposition processes at the giant Taishang gold deposit, Jiaodong Peninsula, eastern China. Ore Geology Reviews, 72(Pt 1): 585-602.
Yang LQ, Guo LN, Wang ZL, Zhao RX, Song MC and Zheng XL. 2017a. Timing and mechanism of gold mineralization at the Wang'ershan gold deposit, Jiaodong Peninsula, eastern China. Ore Geology Reviews, 88: 491-510. DOI:10.1016/j.oregeorev.2016.06.027
Yang LQ, Deng J, Gao X, He WY, Meng JY, Santosh M, Yu HJ, Yang Z and Wang D. 2017b. Timing of formation and origin of the Tongchanggou porphyry-skarn deposit:Implications for Late Cretaceous Mo-Cu metallogenesis in the southern Yidun Terrane, SE Tibetan Plateau. Ore Geology Reviews, 81(Pt 2): 1015-1032.
Ye CQ, Dai WJ, Liu YC and Han XJ. 1988. Discussion on the genesis and prospecting significance of Huangjindong gold deposit. Gold Geological Technology, (2): 24-35.
Zhang J, Deng J, Chen HY, Yang LQ, Cooke D, Danyushevsky L and Gong QJ. 2014. LA-ICP-MS trace element analysis of pyrite from the Chang'an gold deposit, Sanjiang region, China:Implication for ore-forming process. Gondwana Research, 26(2): 557-575. DOI:10.1016/j.gr.2013.11.003
Zhang L, Liu Y, Li RH, Huang T, Zhang RZ, Chen BH and Li JK. 2014. Lead isotope geochemistry of Dayingezhuang gold deposit, Jiaodong Peninsula, China. Acta Petrologica Sinica, 30(9): 2468-2480.
Zhang L, Yang LQ, Wang Y, Weinberg RF, An P and Chen BY. 2017. Thermochronologic constrains on the processes of formation and exhumation of the Xinli orogenic gold deposit, Jiaodong Peninsula, eastern China. Ore Geology Reviews, 81(Pt 1): 140-153.
Zhang W, Zhang ST, Cao HW, Wu DJ, Xiao CX, Chen HJ and Tang L. 2014. Characteristics of chlorite minerals from Xiaolonghe tin deposit in West Yunnan, China and their geological implications. Journal of Chengdu University of Technology (Science & Technology Edition), 41(3): 318-328.
Zhang WL, Hu WX, Hu SX, Zhou SZ and Chen G. 1997. Study on the mode of gold in arsenopyrite from Huangjindong gold deposit, Hunan, by using electron probe microanalysis. Geological Journal of China Universities, 3(3): 256-262.
Zheng ZP, Chen FR and Yu XY. 1997. Characteristics of chlorite in Baguamiao gold deposit and their geological significance. Acta Mineralogica Sinica, 17(1): 100-106.
董国军, 许德如, 王力, 陈广浩, 贺转利, 符巩固, 吴俊, 王智琳. 2008. 湘东地区金矿床矿化年龄的测定及含矿流体来源的示踪——兼论矿床成因类型. 大地构造与成矿学, 32(4): 482-491.
贾宝华, 彭和求. 2005. 湘东北前寒武纪地质与成矿. 北京: 地质出版社: 1-140.
李杰, 陈必河, 安江华, 谭仕敏, 张孝国, 姚宇军. 2011. 湖南黄金洞金矿成矿流体包裹体特征. 华南地质与矿产, 27(2): 163-168.
刘育, 张良, 孙思辰, 綦鹏, 吴胜刚, 高磊. 2017. 湘东北杨山庄金矿床流体成矿机制. 岩石学报, 33(7): 2273-2284.
刘英俊, 孙承辕, 崔卫东, 季峻峰. 1989. 湖南黄金洞金矿床毒砂中金的赋存状态的研究. 地质找矿论, 4(1): 42-49.
刘英俊. 1993. 江南金矿及其成矿地球化学背景. 南京: 南京大学出版社.
罗献林. 1988. 论湖南黄金洞金矿床的成因及成矿模式. 桂林冶金地质学院学报, 8(3): 225-240.
夏浩东, 息朝庄, 邓会娟, 肖晓, 吴圣刚. 2017. 湘东北黄金洞金矿床成因:硫、铅同位素和流体包裹体新证据. 黄金, 38(10): 19-24. DOI:10.11792/hj20171004
许德如, 董国军, 邓腾, 宁钧陶, 王智琳, 邹凤辉. 2015. 湘东北地区大规模金成矿作用及地球动力学背景. 矿物学报, 35(增1): 85.
许德如, 邹凤辉, 宁钧陶, 邓腾, 王智琳, 陈根文, 张建岭, 董国军. 2017. 湘东北地区地质构造演化与成矿响应探讨. 岩石学报, 33(3): 695-715.
薛怀民, 马芳, 宋永勤, 谢亚平. 2010. 江南造山带东段新元古代花岗岩组合的年代学和地球化学:对扬子与华夏地块拼合时间与过程的约束. 岩石学报, 26(11): 3215-3244.
杨立强, 邓军, 王中亮, 张良, 郭林楠, 宋明春, 郑小礼. 2014. 胶东中生代金成矿系统. 岩石学报, 30(9): 2447-2467.
叶传庆, 戴文剑, 刘荫椿, 韩秀军. 1988. 试论黄金洞金矿床成因及找矿意议. 黄金地质科技, (2): 24-35.
张良, 刘跃, 李瑞红, 黄涛, 张瑞忠, 陈炳翰, 李金奎. 2014. 胶东大尹格庄金矿床铅同位素地球化学. 岩石学报, 30(9): 2468-2480.
张伟, 张寿庭, 曹华文, 武俊德, 肖常先, 陈慧军, 唐利. 2014. 滇西小龙河锡矿床中绿泥石矿物特征及其指示意义. 成都理工大学学报(自然科学版), 41(3): 318-328.
张文兰, 胡文宣, 胡受奚, 周顺之, 陈钢. 1997. 湖南黄金洞金矿毒砂中Au赋存状态的电子探针研究. 高校地质学报, 3(3): 256-262.
郑作平, 陈繁荣, 于学元. 1997. 八卦庙金矿床的绿泥石特征及成岩成矿意义. 矿物学报, 17(1): 100-106.