Geology, Mineralogy, and Formation Environment of the Disseminated Gold-Silver Telluride Bulawan Deposit, Negros Occidental, Philippines     

Victor B. MAGLAMBAYAN  †  Daizo ISHIYAMA  Toshio MIZUTA  Akira IMAI  Yohei ISHIKAWA 《Resource Geology》1998,48(2):87-104

Abstract: The Bulawan deposit is located in the porphyry copper belt of southwest Negros island, Philippines. Propylitic, K–feldspar, sericitic, and carbonate alteration types can be distinguished in the deposit. Propylite alteration occurs mainly in Cretaceous-Eocene andesitic lavas and agglomerates while K–feldspar, sericite and carbonate alteration types occur mostly in the Middle Miocene dacite porphyry breccia pipes and stocks which were intruded into the andesites. K-feldspar zones occur in the inner parts of the sericitized zone. Sericite alteration overprinted the propylitized and K-feldspar alteration zones, at lower temperature than epidote and chlorite in the propylitized zone. Carbonate alteration is associated with the mineralization in the center of the breccia pipes and along faults. Mineralization consists of gold-silver telluride ores that are hosted by the carbonate– and sericite-altered dacite porphyry breccia pipes. The Bulawan ores occur mainly as disseminations, but unlike many epithermal gold deposits, lack classical epithermal colloform and crustiform quartz veins. The ore minerals are sphalerite, galena, chalcopyrite, pyrite and tetrahedite-tennantite with minor amounts of electrum, calaverite, petzite, sylvanite, hessite, tellurobismuthite, coloradoite, altaite, and rucklidgeite. Electrum and telluride minerals are associated mostly with calcite and dolomite-ankerite minerals. Fluid inclusions in quartz and calcite in clasts of propylitized andesite in the breccia pipes homogenize from about 300° to 400°C while fluid inclusions in quartz, calcite and sphalerite within the dacite porphyry breccia pipes homogenize between 300° to 310°C. The ores were formed around 300°C from hydrothermal solutions with salinity of about 6. 6 wt % NaCl equivalent. The presence of sylvanite and calaverite as intergrowths with each other, and the Ag content of calaverite are consistent with the above temperature estimate. Based on paragenesis, the Bulawan deposit formed in a pyrite-stable environment, with pH between 3. 4 and 5. 5, f_O2 between 10^-32 to 10^-30 atm, f_S2 between 10^-9.8 to 10^-7.8 atm, f_Te2 between 10^-8.9 to 10^-6.5 atm, and total sulfur content about 10^-2.8 molal. The dominant reduced sulfur species in the ore solutions may have been H₂S_(aq), and the likely aqueous tellurium species were H₂Te_(aq) and H₂TeO_3(aq). The ore minerals in the Bulawan deposit were probably formed by mixing of slightly saline and low salinity fluids.  相似文献   

Mineral Potential of Myanmar     

SOE WIN  MARLAR MYO MYINT 《Resource Geology》1998,48(3):209-218

Abstract: Myanmar is rich in mineral resources, and of potential importance are the deposits of antimony, chromium, nickel, PGM, copper, gold, lead, zinc, silver, tin and tungsten, which form district metallogenic provinces within the six geomor–phic–tectonic units. In terms of past production and potential mineral wealth Myanmar ranks high among Asian countries. The last few decades witnessed a dramatic fall in mineral production, but undoubtedly, the high level of mineral potential remains unrealized. This paper reveals mineral belts with a high level of economic potential which form attractive targets for mineral exploration and some individual mineral deposits of significant magnitude and grade, creating opportunities for development and mining investment.  相似文献   

稀矿山式铁铜矿床与奥林匹克坝式铜多金属矿床的对比研究   总被引：3，自引：0，他引：3  

吴健民  黄永平 《矿产与地质》1998,12(2):79-85

东川稀矿山式铁铜矿床与奥林匹克坝式铜、铀、金、稀土矿床对比研究表明,有其相似的地质构造背景和某些相近的成矿特征,但在某些成矿条件和矿化特征上又存在较大的差异。因此,在我国某些地质构造环境有利,稀矿山式铜多金属矿发育的地区,提出寻找类似奥林匹克坝式超大型铜多金属矿床,同时也应该注意稀矿山式铁铜矿床的成矿特征和评价标志。  相似文献   

福建地壳各岩类铜元素丰度及铜的矿源层（岩）讨论     

王绍雄 《福建地质》1998,17(1):35-43

根据福建省最新岩石测量成果得出的各岩类铜元素丰度,讨论和初步确定了福建铜的矿源层（岩）。提出可按照丰度值高低,铜的初始赋存状态与被解离的难易,有无矿床（点）及具找矿意义的异常产出这３项因素,进一步将矿源层（岩）划分为较可靠的、可能的和潜在的３个级别。  相似文献   

滇池螺蛳(Margarya melanioides)分布和底泥营养元素调查     

沈兰  范彪  田明  张璐  方福康  陈元晓 《海洋科学》2015,39(11):26-31

研究了滇池螺蛳(Margarya melanioides)分布和底泥营养成分之间的关系。2013年在滇池87个采样点采集螺蛳和底泥样本,图示分析所有采样点的活的螺蛳数量,确定活螺在滇池中的分布位点及分布密度;选择8个采样点的底泥样本,进行16项营养元素(有机质、磷、氮、锌、铁、锰、镁、钙、铜、钠、钾、砷、汞、铅、镉、铬)含量测定,分析这些样本营养元素的差异。根据这8个采样点中有无螺蛳生长,将8个底泥样本分为两组,采用完全随机设计两样本比较的t检验,结果两组样本间仅铜的含量有统计学差异(P0.05),这可能是由于滇池螺蛳的生长有效富集了重金属铜元素,使有螺区域比无螺区域底泥中铜的含量明显减少。这在一定程度上说明了螺蛳生长与底泥的关系,可为滇池污染防治及螺蛳种群保护提供相关的科学依据。  相似文献   

吡啶硫酮类防污剂对华美盘管虫早期不同发育阶段的毒性效应研究     

商群  陈新  王超超  葛天宇  曹瑞  朱秀琴  徐利婷  唐敏 《海洋科学》2015,39(9):33-38

以中国南海常见的多毛类——华美盘管虫(Hydroides elegans)作为受试生物,分别研究了吡啶硫酮铜和吡啶硫酮锌对早期不同发育阶段的华美盘管虫的急性毒理效应。发现暴露于吡啶硫酮铜的华美盘管虫精子和卵子的受精半数抑制浓度(IC50)分别为19.49μg/L和88.44μg/L,担轮幼虫24 h半数致死浓度(24h-LC50)和48 h半数致死浓度(48h-LC50)分别为7.35μg/L和5.00μg/L,后担轮幼虫24h-LC50和48h-LC50分别为8.57μg/L和5.87μg/L;暴露于吡啶硫酮锌的华美盘管虫精子和卵子的受精IC50分别为36.74μg/L和159.59μg/L,担轮幼虫24 h-LC50和48 h-LC50分别为8.57μg/L和6.67μg/L,后担轮幼虫24 h-LC50和48 h-LC50分别为12.03μg/L和8.07μg/L。表明华美盘管虫早期发育的不同阶段对吡啶硫酮铜和吡啶硫酮锌的敏感性表现出一定差异,与配子受精率和后担轮幼虫的毒性反应相比,担轮幼虫对吡啶硫酮铜和吡啶硫酮锌的毒性表现出较高的敏感性;而且,对吡啶硫酮铜的敏感性普遍高于吡啶硫酮锌。  相似文献   

Effects of waterborne Cu and Cd on anti-oxidative response,lipid peroxidation and heavy metals accumulation in abalone Haliotis discus hannai ino     

Lei  Yanju  Zhang  Wenbing  Xu  Wei  Zhang  Yanjiao  Zhou  Huihui  Mai  Kangsen 《中国海洋大学学报(英文版)》2015,14(3):511-521

The aim of this study was to compare the effects of waterborne copper(Cu) and cadmium(Cd) on survival, anti-oxidative response, lipid peroxidation and metal accumulation in abalone Haliotis discus hannai. Experimental animals(initial weight: 7.49 g ± 0.01 g) were exposed to graded concentrations of waterborne Cu(0.02, 0.04, 0.06, 0.08 mg L-1) or Cd(0.025, 0.05, 0.25, 0.5mg L-1) for 28 days, respectively. Activities of the anti-oxidative enzymes(catalase, CAT; superoxide dismutase, SOD; glutathione peroxidases, GPx; glutathione S-transferase, GST), contents of the reduced glutathione(GSH) and malondiadehyde(MDA) in the hepatopancreas, and metal accumulation in hepatopancreas and muscles were analyzed after 0, 1, 3, 6, 10, 15, 21, 28 days of metal exposure, respectively. Results showed that 0.04 mg L-1, 0.06 mg L-1 and 0.08 mg L-1 Cu caused 100% death of abalone on the 21 st, 10 th and 6th day, respectively. However, no dead abalone was found during the 28-day waterborne Cd exposure at all experimental concentrations. Generally, activities of SOD and GST in hepatopancreas under all Cu concentrations followed a decrease trend as the exposure time prolonged. However, these activities were firstly increased and then decreased to the control level and increased again during Cd exposure. Activities of CAT in all Cu exposure treatments were higher than those in the control. These activities were firstly increased and then decreased to the control level and increased again during Cd exposure. Contents of MDA in hepatopancreas in all Cu treatments significantly increased first and then decreased to the control level. However, the MDA contents in hepatopancreas were not significantly changed during the 28-day Cd exposure. The metals accumulation in both hepatopancreas and muscles of abalone significantly increased with the increase of waterborne metals concentration and exposure time. These results indicated that H. discus hannai has a positive anti-oxidative defense against Cu or Cd. In conclusion, anti-oxidative mechanism in abalone to resist waterborne Cu did not follow the same pattern as that for waterborne Cd.  相似文献   

青海省都兰县郭勒纸铜矿区地质特征及找矿前景浅析     

王彦明  李军  张国权 《山东国土资源》2015,31(8)

工作区位于东昆仑山脉中段,布尔汗布达山南坡。区域上断裂构造较为发育,岩浆活动频繁,岩浆热液以及岩浆期后热液活动强烈,为成矿元素的进一步活化、运移、富集创造了条件。该文对区内的成矿地质背景、矿床地质特征,矿石特征、矿床成因及控矿因素进行研究分析,认为该矿床有着较好的找矿前景。同时也确定地层标志、构造标志、蚀变标志为其找矿标志,以指导后续普查工作的有效进行。  相似文献   

江西德兴铜矿田成矿热液演化过程及其对铼差异性富集的制约     

陈涛亮  任志  冷成彪  王安东 《地质学报》2023,97(6):1900-1916

铜厂和富家坞矿床是德兴矿田中两个典型的斑岩铜矿床,二者成矿时代、成矿背景和致矿斑岩均较一致,但前者中辉钼矿的Re含量明显高于后者。为探究成矿流体演化过程对辉钼矿中Re含量差异的影响,本文对铜厂和富家坞不同成矿阶段的石英开展LA- ICP- MS微区原位分析以及流体包裹体测温研究。结果显示,二者流体均具有由高温向低温,中低盐度高盐度共存向低盐度演化的趋势,且温度下降、流体沸腾以及pH值的变化可能是导致Cu、Mo沉淀的主要原因;但就同一成矿阶段而言,铜厂比富家坞成矿温度更低,并且在主成矿阶段,铜厂具有更高的流体盐度;因此,推测温度和盐度可能是导致二者中辉钼矿Re含量差异的主导因素。  相似文献   

Biochemical‐genetic and meristic evidence that blue and copper moki (Teleostei: Latridae: Latridopsis) are discrete species     

P. J. Smith  C. D. Roberts  P. G. Benson 《新西兰海洋与淡水研究杂志》2013,47(2):387-395

Specimens of blue moki Latridopsis ciliaris (Forster in Bloch & Schneider, 1801) from New Zealand were shown to differ from specimens of copper moki Latridopsis forsteri (Castelnau, 1872) using two genetic methods—allozymes and muscle proteins. Allozyme techniques revealed fixed differences between blue and copper moki at 4 out of 15 loci. There was a genetic distance of 0.31–0.34 between population samples of the two colour morphs. The two morphs were also distinguished by iso‐electric focusing of muscle proteins. Meristic characters, counted in the specimens studied with genetic markers, revealed diagnostic markers in tubed lateral line scales and scales in the lower transverse series. It is concluded that specimens of blue moki from New Zealand and copper moki from New Zealand and Tasmania are valid species.  相似文献