南秦岭Pb,Zn,Ag,Cu,Hg,Sb,菱铁矿成矿系列

以泥盆系占优势的南秦岭成矿带中存在有重要的Ｐｂ－Ｚｎ－Ａｇ，Ａｕ，Ｈｇ－Ｓｂ及Ｃｕ矿床。它们形成中晚古生带扬子地块北部被动大陆边缘的沉积盆地演化与造山期中，成矿系列显示出时间与空间的演化特征，构在了一个热水沉积成矿系列，成矿发生于一个热旋回中，各种矿化有相似的物源，每一种地质事件都有特定的金属富集及富集在型和大型矿床是该地区构造－岩浆变质变形作用的最终产物。     

等离子体质谱法测定岩石中的铌,钽,锆,铪,钍,铀

应用ＩＣＰ－ＭＳ法测定了岩石中的痕量Ｎｂ、Ｔａ、Ｚｒ、Ｈｆ、Ｔｈ、Ｕ，给出了检出限，并对酸溶和碱熔两种制样方法进行了对比实验。     

Quaternary： status, rank, definition, survival

The long controversy over the term ‘Quaternary‘ as a chronostratigraphic unit may be reaching an apotheosis, judging from recent papers (Pillans and Naish, 2004; Gibbard et al., 2005; and referencest herein). The debate is no longer centered on whether there should be a place in the geological time scale for a unit termed ‘Quaternary‘-despite its dubious past, it cannot be denied that a large body of earth-historical research is strongly identified with this term. The challenge now concerns an appropriate rank and definition of Quaternary with regard to other chronostratigraphic units. Several options have been proposed (Pillans and Naish, 2004), and Gibbard et al. (2005) encourage a debate on these before decision is reached. In this brief note, we describe an arrangement not previously considered that seems advantageous. It is instructive, however, to first review the Pleistocene Series and Neogene System, the two units that are directly affected by introduction of the Quaternary into the chronostratigraphic hierarchy.     

大陆漂移,板块构造,地质力学

本文简要地介绍了魏格纳大陆漂移说的主要内容及其提出的依据:论述了在大陆漂移说的基础上,由于海洋地质地球物理调查发现了大洋中脊、洋底扩张,解释了大陆张裂的机制,并建立了全球板块构造理论,形成现代地学思想的革命;李四光在大陆漂移说提出的同时已在积极地探讨和论述大陆地壳水平运动问题,并结合中国大陆实际,发展了陆内碰撞变形理论,即包括全球大陆构造体系在内的地质力学理论和方法.他强调地质力学是一支脚站在地质上,另一支脚站在力学上来研究地壳运动和变形现象.后来更扩大了其在资源、环境方面的应用.文章对魏格纳大陆漂移说、全球板块构造理论及地质力学三者的关系做了深入探讨,论述了李四光地质力学理论方法的现代意义、超前意义,提出要重视和发扬李四光留给中国人民的宝贵遗产,建议深入学习李四光的著述,结合地质调查新成果去丰富它和发展它.     

Source,transport, and fate of rhenium,selenium, molybdenum,arsenic, and copper in groundwater associated with porphyry–Cu deposits,Atacama Desert,Chile

We collected groundwaters in and around a large (313 Mt at 1.08% Cu and 0.3% cutoff) undisturbed porphyry copper deposit (Spence) in the hyperarid Atacama Desert of northern Chile, which is buried beneath 30–180 m of Miocene piedmont gravels. Groundwaters within and down-flow of the Spence deposit have elevated Se (up to 800 μg/l), Re (up to 31 μg/l), Mo (up to 475 μg/l) and As (up to 278 μg/l) concentrations compared to up-flow waters (interpreted to represent regional groundwater flow). In contrast, Cu is only elevated (up to 2036 μg/l) in groundwaters recovered from within the deposit; Cu concentrations are low down gradient of the deposit. The differential behavior of the metals/metalloids occurs because the former group dissolves as anions, enhancing their mobility, whereas the base metals dissolve as cations and are lost from solution most likely through adsorption to clay surface exchange sites and through formation of secondary copper chlorides, carbonates, and oxides. Most groundwaters within and down-flow of the deposit have Eh–pH values around the Fe^II/Fe^III phase boundary, limiting the impact of Fe-oxyhydroxides on oxyanions mobility. Se, Re, Mo, and As are all mobile (with filtered/unfiltered samples ～ 1) to the limit of sampling 2 km down gradient from the deposit. The increase in ore-related metals, metalloids, and sulfate and decrease in sulfate–S isotope ratios (from values similar to regional salars, + 4 to + 8‰ δ³⁴S_CDT to lower values closer to hypogene sulfides, + 1 to + 4‰ δ³⁴S_CDT) is consistent with active water–rock reactions between saline groundwaters and the Spence deposit. It is likely that hypogene and/or supergene sulfides are being oxidized under the present groundwater conditions and mineral saturation calculations suggest that secondary copper minerals (antlerite, atacamite, malachite) may also be actively forming, suggesting that supergene and exotic copper mineralization is possible even under the present hyperarid climate of the Atacama Desert.     

德兴斑岩铜矿田两类伊利石的存在及其在蚀变分带中的意义

德兴斑岩铜矿田内存在两种成因类型的伊利石：一是特征的热液蚀变矿物,它是在热液流体 作用过程中斜长石、云母类矿物通过伊利石化过程形成的,其结晶度(IC)和膨胀层含量受携 带矿质的热液流体量控制;二是浅变质作用自身的产物,其结晶度远较小于前者,具2M1 多型,且不含膨胀层,是原始蒙皂石完全伊利石化形成的。作者发现,在斑岩体和接触带内 ,伊利石结晶度小的部位,蚀变程度强,矿化品位也高。     

成矿流体对德兴斑岩铜矿床中伊利石结晶度的控制作用

伊利石广泛存在于铜厂大型斑岩铜矿床内,是特征的热液蚀变矿物,其结晶度和膨胀层含量受携带矿质的热液流体量控制。以浸染状强矿化为特征的斑岩体中上部及接触带附近伊利石结晶程度较好,主要是高水／岩比作用的结果。同时指示出伊利石结晶程度好的部位,矿化品位高,蚀变程度也强。     

介绍一种寻找隐伏岩体的好方法:岩浆热场法

隐伏岩体对于热液矿床找矿是非常重要的。寻找隐伏岩体的方法很多,其中以物探(磁法、电法、重力、地震等)方法应用得最广泛、效果最好。本文介绍的岩浆热场法,是专门寻找隐伏岩体的方法。岩浆热场法是地球物理方法的一种,它以感知温度场的差别为目的,没有多解性是它最大的优点。它以岩浆热场理论为基础,以各种能够恢复古温度场的方法为手段。能够感知岩浆热场温度的方法很多,本文介绍了其中的五种:接触变质带法、煤质和煤级法、伊利石结晶度法、牙形石色变度法和镜质体反射率法等。接触变质带是岩浆热场直接的具体的体现,传统的接触变质带范围有限(一般不超过1km)。但是,如果考虑到极低级变质作用,将大大扩展接触变质带的范围(达6~8km)。煤质和煤级是煤田地质部门应用得非常娴熟的方法,中国无烟煤分布区大多与岩浆热场有关,是隐伏岩体的良好指示剂。伊利石结晶度、牙形石色变度和镜质体反射率法是极低级变质作用研究中非常重要的三个指标。在上述各种方法中,笔者推荐镜质体反射率方法。该方法具有简单、精确、适用、经济、快速的特点。与物探方法比较,该方法有很多优点,但也有其局限性。如果能够将该方法从煤田和石油部门移植到岩石学和矿床学部门,与磁法、电法、重力法配合使用,可以提高寻找隐伏岩体的效果。     

武当-桐柏-大别成矿带铜矿成矿规律

武当-桐柏-大别成矿带可分为南秦岭造山带、北淮阳构造带、桐柏-大别构造带三个二级构造单元,在南秦岭造山带广泛分布变质热液型铜矿,北淮阳构造带内产出VMS型、岩浆熔离型及斑岩型铜矿,桐柏-大别构造带则分布有岩浆热液型和矽卡岩型铜矿。构造单元的性质对区内产出的铜矿类型具有较强的控制作用。变质热液型铜矿主要与浅变质作用有关,变质流体以断层为运移通道并最终就位于黑色岩系内的次级断层。VMS型、岩浆熔离型、斑岩型铜矿与岩浆作用密切相关,产出在岩体内部及与围岩的接触带。岩浆热液型及矽卡岩型铜矿形成于岩浆作用晚期阶段,分布在岩体与围岩接触带及附近构造裂隙带等部位。     

江西银山多金属矿床伊利石的形成与流体成矿作用的初步研究

江西银山多金属矿床的热液蚀变粘土矿物主要由伊利石组成,伊利石主要由流体作用过程中长石的伊利石化形成,其结晶度与成矿流体作用密切相关.银山第1期铅锌银成矿作用,水/岩比相对较低,成矿流体以孔隙渗透为主,溶质迁移慢,形成含有少量膨胀层的伊利石;第2期铜金成矿作用,水/岩比相对较高,流体的运移方式以通道式或裂隙式为主,溶质迁移的速度快,形成不含膨胀层的伊利石.研究表明成矿作用过程中的伊利石化主要与铅锌银矿化有关,而绿泥石化与铜金矿化有关.     

Kübler Index and K-Ar Ages of Illite in the Yinshan Polymetallic Deposit, Jiangxi Province, South China: Analyses and Implications

Abstract. The Yinshan polymetallic deposit is a hydrothermal vein-type deposit closely related to Late Jurassic felsic-inter-mediate volcanic-subvolcanic activity in Jiangxi Province, South China. Illite is a major alteration mineral observed in the deposit. Our study shows that the Kübler index of the illite has a close relation to ore-forming fluids of different stages of hydrothermal alteration and mineralization. The early Pb-Zn-Ag mineralization dated at 130–136 Ma is characterized by relatively low water/rock ratios and diffusive fluid movement within phyllite, whereas the later Cu-Au-S mineralization at 122 -125 Ma was accompanied by higher water/rock ratios and localized fluid flow through fractures and channels. Illite formed in the early Pb-Zn-Ag mineralization stage contains swelling layers while the illite formed in the later Cu-Au-S mineralization stage has no swelling layers but was associated with intensive chloritization. The last stage of mineralization (at 104 Ma) was minor and did not produce significant amounts of illite.     

陕西省山阳县池沟地区斑岩成矿特征、成矿规律及找矿预测

池沟地区小斑岩体广泛发育,岩体多呈北东向展布的申珠状小岩株或岩枝产出,属燕山期高钾钙碱性系列Ⅰ型花岗岩,具(似)斑状特征.区内出现有与燕山期岩浆活动有关的斑岩型铜矿、斑岩型钼矿、矽卡岩型铜矿、构造蚀变岩型金矿等4种类型金属矿化.蚀变、化探异常及矿化均围绕斑岩体呈(环)带状分布,由岩体往外依次出现钼、铜、金矿化的分带性,...     

由伊利石结晶度研究桂西右江地区区域极低级变质作用

运用伊利石结晶度Kübler指数将桂西右江地区下三叠统罗楼群和中三叠统百逢组下段划归为浅层变质带(K.I△2θ°为0.22～0.25);将中三叠统百逢组上段和河口组划归为近变质带,中三叠统百逢组上段为高级近变质带(K.I△2θ°为0.26～0.33);中三叠统上部河口组为低级近变质带(K.I△2θ°为0.38～0.40),不排除局部为成岩带的可能.地层柱自下向上,伊利石结晶度Kübler指数由小变大,变质程度由高变低,而且,变质作用级别与岩层在地层柱中位置协调以及变质带边界与地层界线趋于一致,证明为区域埋藏极低级变质作用.凌云明山金矿区剖面矿体和百逢组各层段伊利石结晶度Kübler指数为0.42～0.50,属成岩带,且没有明显时空变化规律.     

甘肃岗岔—克莫地区蚀变岩特征与找矿预测

岗岔—克莫金矿区位于西秦岭北缘夏河—合作成矿带,具浅成低温热液型矿床特征,初步显示深部可能具有斑岩成矿系统存在。利用短波红外光谱矿物分析技术对岗岔—克莫金矿区蚀变岩特征的研究表明,矿区内发育的蚀变矿物主要有白云母、伊利石、蒙脱石、高岭石、地开石、绿泥石、绿帘石和次生石英等。近矿蚀变类型主要为绢英岩化。矿区内以下家门沟口为中心向外依次发育了中心带(绢英岩化带)、过渡带(泥化带)和外围带(青磐岩化带)。此外,伊利石结晶度以下家门沟口为中心向外具有明显的降低趋势。研究结果指示下家门沟口可能是矿区的热液活动中心。     

新疆西昆仑金(铜)矿找矿前景分析

位于塔里木西南缘的木吉－大同一库地金铜成矿带是西昆仑地区重要成矿带,带内金矿主要产于碳质千枚岩、碎屑岩及绢去母石英片岩等岩石中,受韧性剪切带及构造蚀变带控制。铜（金）矿化与华力西期花岗岩类关系较紧密,金铜找矿以海相喷流沉积型铜（金银）矿、斑岩及夕卡岩型铜金矿、构造蚀变岩型金矿及韧性剪切带型金矿为主,根据金铜成矿环境分析,认为该区的金铜找矿潜力巨大。