山西省代县滩上一带隐爆角砾岩地球物理和地球化学特征及其地质意义

隐爆角砾岩型金矿是国内外一种具有重要经济价值的矿床类型。在分析山西代县滩上隐爆角砾岩区的金多金属矿床地质背景、地球物理及地球化学特性的基础上,研究滩上一带隐爆角砾岩的岩石化学特征,发现该区金多金属矿体赋存部位位于岩体内、内外接触带及四集庄组岩组捕虏体中。研究认为,金多金属矿由石英斑岩中硫化物局部富集形成,其主要物质来源与滩上岩体之岩浆期后热液有关,黄铁矿化隐爆角砾岩为容矿岩石,断裂及其次级断裂、裂隙等构造活动为金矿体的形成提供了良好的导矿通道,燕山期中酸性浅成-超浅成岩浆活动为研究区成矿提供了大量含矿热液和成矿物质。     

水力压裂技术对江西相山热液铀矿成因的启示

水力压裂技术是页岩气开采的关键技术,水力压裂技术对江西相山热液铀矿成因研究提供了重要启示。华南相山矿田火山侵入岩浆活动频繁,在不同类型的侵入岩成岩的晚期发生了明显的隐爆作用,产于相山火山侵入杂岩体中的热液铀矿床,铀等成矿物质主要来源于火山侵入杂岩本身,铀的搬运主要是以碳酸铀酰络合物形式沿隐爆裂隙进行,铀的沉淀是隐爆地震发生后的降压作用引起的,隐爆碎屑岩是主要的成矿地质体,水力压裂是铀成矿的动力学机制,铀矿化是隐爆作用的必然产物。     

东准噶尔成矿带岩浆隐蔽爆破作用与成矿

新疆东准噶尔地区乌伦布拉克铜矿、老山口铜—铁—金矿两地皆存在花岗质岩浆隐蔽爆破作用。前者形成了与潜火山英安玢岩侵入体密切伴生的英安玢岩质隐爆角砾岩,后者形成了与潜火山闪长玢岩侵入体相伴生的闪长玢岩质隐爆角砾岩和闪斜煌斑岩质隐爆角砾岩。岩浆隐蔽爆破作用是伴随该区华力西中晚期—晚期地槽褶皱造山运动而发生的一种超浅成岩浆作用,其与铜、金等金属成矿的关系密切;与其有关形成了隐爆角砾岩筒型铜(金)矿和破碎带蚀变岩型金矿。两种类型的矿床都显示出广阔的找矿前景。     

山东五莲七宝山地区长老庄隐爆角砾岩带特征及意义

七宝山金铜矿位于胶莱盆地西南缘的七宝山地区,在金铜矿外围新发现长老庄含矿隐爆角砾岩带一条, 物探解译工作初步查明了该隐爆角砾岩带地质及地球物理特征：位于激电中梯高阻和低阻接触带上,深部呈低阻、中高激化异常。经钻探验证,在深部发现高品位的银铜铅矿体,矿石中粗粒方铅矿、黄铜矿结晶体肉眼可见,呈团块状富集,铜品位0.493%～5.125%,铅品位0.245%～6.606%,银品位55.2～547.1g/t。表明在金铜矿外围及深部仍具有寻找隐爆角砾岩型高品位银铜铅矿体的潜力。     

安徽宣城茶亭铜金矿床隐爆角砾岩特征及其成矿意义

安徽宣城茶亭铜金矿床是近年来在长江中下游浅覆盖区之南陵—宣城中—新生代火山—沉积盆地中新发现的一个大型矿床。文章以赋矿石英闪长玢岩侵入体内发育的隐爆角砾岩为对象,通过详细的钻孔岩心观察和显微岩相学研究,确定其地质特征并探讨其与成矿的关系。根据钻孔岩心观察确定的岩石构造特征及钻孔剖面圈定的角砾岩空间分布特征,茶亭铜金矿床发育的隐爆角砾岩呈上大下小的不规则筒状体,被隐伏的石英闪长玢岩侵入体包孕。根据角砾特征以及角砾间的裂隙和胶结物特征,可将隐爆角砾岩划分为隐爆浆屑角砾岩、隐爆热液角砾岩和隐爆破裂角砾岩三类,三类隐爆角砾岩空间上有规律地分布,以隐爆浆屑角砾岩为中心向外或向上依次过渡为隐爆热液角砾岩→隐爆破裂角砾岩→石英闪长玢岩。基于隐爆角砾岩与蚀变和矿化的关系推测,岩浆—气液隐蔽爆破作用所产生的大量裂隙为后期含矿岩浆热液和大气降水热液的运移、交代、混合乃至卸载、沉淀成矿提供了有利的构造空间。茶亭铜金矿床的矿体赋存于浅成斑岩侵入体中,其围岩蚀变类型与分带,以及矿化呈细粒浸染状和细脉—网脉状等地质特征显示其与斑岩型矿床极为相似,但矿化富集部位与隐爆角砾岩筒（体） 的一致,且矿床同时发育角砾状、脉状、团块状矿化,矿脉中发育热液硬石膏甚至形成硬石膏岩等地质特征又明显不同于斑岩型矿床。因此,文章将茶亭铜金矿床确定为一个与中酸性浅成斑岩侵入体密切相关的隐爆角砾岩型矿床。     

流体参与下的岩石破裂机制及其分形特征

流体参与下的岩石破裂机制一般分为爆发作用、流化作用和液压致裂等,其分维值大小一般遵循爆发作用→流化作用→液压致裂.通过对凤凰山铜矿II号矿体不同地段的角砾岩进行分形统计分析,判明其属于液压致裂角砾岩,验证了分维值的大小与致裂能量之间的正相关关系.     

云南金顶超大型铅锌矿床沥青Re-Os法测年及地质意义

油气藏与金属矿床在世界许多沉积盆地内共存,油气成藏与金属成矿的动力学关系备受关注。云南兰坪金顶产有中国目前最大铅锌矿床,也是世界上唯一陆相沉积岩容矿、且形成于新生代的超大型铅锌矿床。矿床中常见沥青、重油等有机质,它们的形成早于或晚于铅锌硫化物成矿存在明显分歧,限制了对油气成藏与铅锌成矿关系的认识。本文针对金顶超大型矿区以古新统云龙组含砾砂岩和砂砾岩为主岩铅锌矿石中沥青,开展了Re-Os法同位素测年,获得68±5Ma的等时线年龄(MSWD=9.2,n=6),指示金顶古油气成藏形成于古新世,先于铅锌硫化物大规模成矿;烃类物质具有通过热化学还原硫酸盐提供铅锌成矿所需硫化氢的客观条件;油气成藏与铅锌成矿在云南金顶矿区很可能是一个先后发生的连续地质过程,成藏为成矿奠基,成矿伴随着油气藏的破坏。     

烟筒桥子金矿床3号矿体地球化学特征及其找矿标志

烟筒桥子金矿床是以隐爆角砾岩筒型矿化为主体的金矿床,以矿区3号矿体为主要对象,通过对该矿体岩、矿石微量元素的地球化学分析,探讨了该类矿体地球化学特征。结果表明,在所分析的12种元素中,Au与Ag、Bi、Pb和Zn元素具有相似的富集趋势。这些元素的的富集规律可用于隐爆角砾岩体中金矿体的找矿标志之一。     

福建宁德九曲岭含铜钨矿隐爆角砾岩筒地质特征及其找矿意义

宁德九曲岭含铜钨矿隐爆角砾岩筒出露于花岗闪长岩体之中,未见明显断裂控制。隐爆角砾成分与胶结物成分复杂,矿化蚀变具明显的分带特征,其中铜钨矿贮存于黄铁矿一绿泥石和石英一绿泥石带中。外围尚发现2个大型隐爆角砾岩筒,通过研究九曲岭铜钨矿角砾岩筒特征,对指导深部与外围找矿具有重要找矿意义。     

Tellurium-Gold Mineralization Related to Cryptoexplosive Breccias within Volcanic Pipe in Zhuojiazhuang Gold Deposit,Shandong Province, China

Zhuojiazhuang gold deposit (ZGD) is the most enriched breccia pipe type gold deposit in East China, resulted from cryptoexplosion related to alkalinic magmatism and orebearing fluid filling. The ZGD is a small-sized mine with over 5 tons of gold reserves and grade of 156g/t in average and the highest 2 728 g/t as known. In addition, tellurium and silver are also valuable.The mineralized breccia pipe is cylinder-like in shape with 15 m long and 10 m wide and controlled by intersection ofNW and EW trend faults. Mining level has reached 170 m below the surface, but the whole pipe mineralization is still stable. Mineralization commonly occurs within the cements of breccias. Gold ores consist of hydrothermal breccia ore, shatteredbreccia ore and cataclastic ore. From the center of the ore body outwards, there is the transition from hydrothermal breccia toshattered breccia and then to cataclastic ores. According to composition and amount of the cements, the hydrothermal brecciaores can further be divided into three subtypes: sulfides cemented, hydrothermal mineral cemented and magma cemented.The content of gold is closely related to the types of the cements. The grade of the sulfide cemented breccia is the highestone, usually more than 1 000 g/t, and the known maximum grade is 2 728 g/t. The composition of the shattered breccia ismainly dioritic porphyrite and cemented by hydrothermal minerals, the grade ranges from ten to several tens g/t. The catsclastic ores are mainly composed of dioritic porphyrite, syenitic porphyry, as well as carbonate with mineralized veins, and the grade is only 35 g/t.Major ore minerals consist of pyrite, native tellurium, sphalerite, with minor calaverite, galena and altaite. Gangueminerals are composed of microcrystalline quartz, decktite and fluorite, with minor sericite and calcite. Brecciated and disseminited structures are main structures of ores. Four ore-forming stages are defined: microcrystalline quartz-pyrite stage,microcrystalline quartz-polymetal sulfides stage, quartz-adular stage and dickite stage. Wall rock alteration is characterized bysilicification, sericitization, adularization and fluoritization.The enrichment of tellurium may indicate that the ore-forming fluid was of a deep origin from upper mantle or lower crust. Mineral assemblage of microcrystalline quartz, fluorite, adularia and dickite suggest a relatively low-temperature forming condition. An extensive suite of elements, including Au, Ag, Te, Hg, Sb, As, Mo, F, Zn, and Tl, is significantly enriched in mineralized rocks. They can be geochemical indicators for exploration in the study area.Comprehensive studies show that the Zhuojiazhuang gold deposit is a type of sericite-adular gold deposit, belongs to epithermal gold deposits, or can be classified into alkali gold deposit series.