我国首次发现的银镍黄铁矿     

莫少剑 《矿物学报》1986,(2)

我国的银镍黄铁矿产于广西融水县九毛锡矿区,粒度极细,反射率为25.9(470nm),34.8(546nm),35.8(589nm),39.7(650nm)。成分中含Ag 11.12—13.26％,Ni 19.06—23.07％,Fe 31.27—35.13％,Co 0.02—0.34％,Cu 微—4.70％,S 30.87—32.99％。  相似文献   

Relation between the concentrations of DMS in surface seawater and air in the temperate North Pacific region     

Shuichi Watanabe  Hiroshi Yamamoto  Shizuo Tsunogai 《Journal of Atmospheric Chemistry》1995,22(3):271-283

The concentrations of DMS were simultaneously measured in both water and air at the sea surface on board a vessel during a trans-Pacific cruise around 40° N in August 1988. Those in the surface seawater varied widely with a mean of 162 ng S/1 and a standard deviation of 134 ng S/1 (n=37), but the variation was not a mere fluctuation and the high concentration (376 ng S/1) was found in the area between 145° W and 170° W. The atmospheric DMS concentration varied more widely with a mean value of 177 ng S/m³ and a standard deviation of 203 ng S/m³ (n=23). The diurnal variation of DMS was not significant in the air near the sea surface. However, the concentrations in the surface water was fairly well correlated with those in the surface air. The correlation coefficient (r ²=0.86) was larger than that between the atmospheric concentration and outflux of DMS (r ²=0.64). These findings mean that the turnover time of DMS in the atmosphere is not extremely short. Based on the linear relation between the atmospheric and seawater DMS, the turnover time of the atmospheric DMS has been calculated to be 0.9 days with an uncertainty of around 50%. The oxidation rate agrees fairly well with that expected from the OH radical concentration in the marine atmosphere.  相似文献   

北祁连山构造－火山岩浆演化动力学   总被引：44，自引：0，他引：44  

夏林圻  夏祖春  徐学义 《西北地质科学》1995,(1)

笔者以区域构造－火山岩浆演化动力学为主线，从研究区域火山岩岩石学的角度探索北祁连山古板块构造体制与火山岩浆作用的关系，主要强调区域上不同特点火山岩的成因，其形成应直接与构造环境有关。作者的研究查明，从元古代末至泥盆纪，北祁连山经历了一个由大陆裂开→大洋化→洋盆扩张并俯冲消减→沟、弧、盆体系形成和完善→洋盆收缩闭合→碰撞造山的全过程，每一阶段均发育有相应岩石地球化学特征的海相火山活动。经确定有如下５种特定的火山岩浆产生环境：（１）元古代末－寒武纪大陆裂谷型火山作用，（２）寒武纪末－早奥陶世洋脊－洋岛型火山作用，（３）奥陶纪岛弧火山作用，（４）中－晚奥陶世弧后盆地火山作用，（５）晚奥陶世－志留纪海盆闭合期火山作用。作者的研究揭示，海底块状硫化物矿床的形成与拉张环境下火山岩浆的产生密切相关。因为海底循环的热卤水在此类矿床的形成中起着决定作用，而这种循环作用受与拉张环境相伴的局部高热流和海底火山活动所驱动。  相似文献   

麒麟厂铅锌矿银的工艺矿物学研究   总被引：4，自引：1，他引：4  

王静纯 《矿物学报》2001,21(3):531-533

笔者应用微区测试研究、粒度统计分析及物相分析等，对云南会泽铅锌矿麒麟厂矿床6号矿体铅锌特富矿石中银的工艺矿物特征进行了研究，认为银以类质同象和独立矿物两种状态存在，发现了11种银矿物和含银矿物，方铅矿是银的主要载体矿物，银的最佳回收指标为93．52％－99．20％。  相似文献   

红太平多金属矿床地质特征及区域找矿意义   总被引：1，自引：0，他引：1  

宋群 《吉林地质》1991,10(4):22-28

红太平多金属矿床产于延边古生代地槽区二叠系海相火山岩中及其与碎屑沉积岩的过渡带上。矿体呈层状,矿石具典型的沉积构造,矿石硫同位素组成与国内变质火山岩铜矿床相似,气液包裹体氢氧同位素组成介于大气循环水和变质水之间。因此,初步认为矿床属与火山热液或热泉活动有关的块状硫化物型矿床。  相似文献   

安徽庐江巴家滩岩体岩浆结晶的物理化学条件及其研究意义     

任启江  杨荣勇  孙冶东  吴启志  王实  徐兆文  吴长年  邱检生 《矿物岩石》1991,(3)

对巴家滩杂岩体造岩矿物的研究和岩石的熔融实验,确定岩浆结晶温度区间为775—920℃,压力为p=50MPa。岩浆体系具有较低的fH_2O和较高的fO_2,其T-fO_2变异曲线不同于宁芜玢岩铁矿的母岩浆,对铁质在岩浆演化过程中的富集不利,但有利于贱金属硫化物矿床的形成。  相似文献   

白银厂块状硫化物矿床成矿地球化学环境   总被引：3，自引：0，他引：3  

黄玉春 《西北地质科学》1992,(1)

根据稳定同位素地球化学和包裹体测试结果等资料阐述了成矿溶液的性质、成矿物理化学条件及成矿金属组分迁移、沉淀机制,用大本模式图解模拟了成矿过程中物化条件演化趋势,重溯了成矿时的地球化学环境,并在此基础上解释了白银厂矿床为Cu-Zn型矿床的原因。  相似文献   

Grab sampling for the determination of sulfur dioxide and dimethyl sulfide in air by isotope dilution gas chromatography/mass spectrometry     

Byron W. Blomquist  Alan R. Bandy  Donald C. Thornton  Shaoming Chen 《Journal of Atmospheric Chemistry》1993,16(1):23-30

Developments allowing the direct determination of sulfur dioxide and dimethyl sulfide in grab samples by gas chromatography/mass spectrometry with isotopically labeled standards (GC/MS/ILS) are reported. Isotopomers of DMS and SO₂ are used as internal standards. Spiked air samples are dried to a dew point of <–60 °C and trapped cryogenically in loops of Teflon tubing. Sealed samples are transported to the laboratory under liquid nitrogen and later subjected to GC/MS analysis. Holding times of up to one month do not result in significant sample loss. For samples collected in a clean marine environment, concentrations of SO₂ and DMS greater than 5 and 8 pptv, respectively, are significantly different from blanks at the 95% confidence level. Average measurement precision derived from a propagation of errors are 9% for SO₂ and 42% for DMS at concentrations from 5–15 pptv.Improvements are outlined which should provide sensitivity and precision comparable to that of on-site GC/MS. The technique will allow increased flexibility for the determination of trace sulfur species in the field under conditions where deployment of a mass spectrometer is not possible.  相似文献   

山东招掖金矿带控矿断裂断面迁移规律及其意义     

卢作祥  章增凤  张亚雄 《地球科学》1988,(2)

本文重点探讨了矿体在断裂带内的赋存规律。通过对招掖金矿带内各主要控矿断裂(带)的详细研究,并对其代表性构造岩进行了系统的镜下观察和化学分析,笔者着重论述了控矿断裂断面迁移的存在和演化,并用断面迁移的观点对断裂的控矿机制进行了讨论。文章明确指出,不同形式的断面迁移具有不同的控矿意义,进而总结了矿体在断裂(带)中的产出规律。  相似文献   

The determination of sulfide in seawater by flow-analysis with voltammetric detection     

Radwan Al-Farawati  Constant M. G. van den Berg   《Marine Chemistry》1997,57(3-4)

Preliminary measurements of sulfide in seawater using cathodic stripping voltammetry and a hanging mercury drop electrode (HMDE) in batch-mode showed that the sulfide peak decreased rapidly with time. This decrease was not caused by O₂, H₂O₂ or IO₃⁻, and the sulfide peak was not stabilised by trace metal additions. A home-made flow-cell was constructed to enable the determination of sulfide in seawater using voltammetry with an HMDE. A stable sulfide peak was obtained by flow-analysis with voltammetric detection, with a precision of 2.8% and detection limit of 0.5 nM at a 60 s adsorption time. Several thiol compounds were found to produce a peak at, or very close to, the peak potential for sulfide. Their interference was evaluated by allowing the sulfide peak in conventional (batch) voltammetry to decay. Comparative experiments showed that waste metallic mercury is responsible for removal of sulfide in batch-mode analysis due to formation of insoluble mercuric sulfide salts causing the rapid decay of the sulfide peak. The problem is circumvented by using flow-analysis to determine sulfide.  相似文献