Growth Rate Estimates of Supergene Manganese Nodule by ^(40)Ar/^( 39)Ar Isotopic Dating

Increasing world-class, high-grade, and metals-enriched supergene manganese ore deposits have been discovered in the last two decades, making them more and more economically important. However, data on the timing and duration of their formation are sparse, mainly due to the difficulties extracting datable minerals suited to traditional radiometric dating methods. Hollandite, cryptomelane, coronadite, todorokite, and manjiroite are common manganese oxide minerals in supergene environments. These minerals host potassium of variable amounts from 0.1 wt% to 5.0 wt% in their structural sites. This geochemical property provides possibility to date supergene manganese ores by using K-Ar and 40Ar/ 39Ar methods. In this study, we perform 40Ar/ 39Ar dating on a 7.1-cm-thick botryoidal manganese nodule from an ancient weathering profile at Mount Tabor, central Queensland, Australia. Laser microprobe incremental analyses of distinct growth bands, from the inner core through the intermediate bands to the outermost crusts of the nodule, have yielded high quality 40Ar/ 39Ar ages at 27.3 Ma, 20.9 Ma, 19.2 Ma, and 16.1 Ma, respectively. The age results permit preliminary estimates on the average growth rates of the nodule varying from 4.7×10 -3 mm/ka to 7.6×10 -3 mm/ka to 9.0×10 -3 mm/ka, from the core to the rim. Results of this study are of significance in our understanding of the mode, mechanism, process, and climatic conditions in the formation of supergene manganese ore deposits.

Supergene Geochemistry of Gold and Oxidation Zone of the Sain Us Gold Deposit in the Inner Mongolian Arid Region

The Sain Us gold deposit is a typical auriferous sulphide quartz vein deposit in the InnerMongolian arid steppe climatic region. The oxidation zone has been controlled by the arid cli-mate since the beginning of the Holocene. Gold supergene evolution is characterized by enlarge-ment of gold grains, complication of the gold form, raising of the gold grade and increase of thegold fineness; besides, gold and silver have two enrichment peaks at the same depth, which is insharp contrast to the unimodal enrichment of gold and silver and the occurrence of gold aboveand silver below in a humid climatic region. Sun pumping is the main cause for the bimodalenrichment of gold and silver. Illite 2 M_1 is one of the main causes for the upper enrichment peakof gold and silver.

Mapping Supergene/Hypogene Alteration Signatures with Landsat ETM+ Data: Paishanlou Gold Mine, Liaoning Province, China

Noise removal routines (destriping) were performed on Landsat ETM+ data as adjustments for atmospheric and distortion factors, prior to further image enhancement and interpretation. The image enhancement techniques were contrast stretching, density slicing, spatial filtering, Fourier analysis, brightness inversion, band combinations, and band ratioing. It has been revealed that, owing to the presence of gossans at Paishanlou, the mixture of iron oxide and clay minerals affects the spectral reflectance in satellite data. The mineral and hydrothermal composite images with band ratios 5/7+5/4+3/1 RGB and 5/7+3/1+4/3 RGB, respectively, yielded the best results for their sensitivity to lithologic variables, and lack of statistical redundancy. Ratio 3/1 clearly highlighted ferric (Fe 3+ ) iron; 5/4 depicted ferrous (Fe 2+ ) iron, and 5/7 depicted clays, carbonates, and hydroxyl bearing minerals. Vegetation was also successfully discriminated by ratio 5/7. Finally, coupled with field surveys, petrographical and geochemical data, the observed anomalies led to the discovery of three new sites, which are gold mineralized. The prime objective of this study was to map supergene and/or hypogene signatures in the gold mineralized areas using Landsat ETM+ data at Paishanlou.

Using homology primers to clone a novel gene of β-chemokine receptorsupergene-family

Objective Using homology primers for clone of β-chemokine receptor supergene-family from lower level RNA expression. Methods: Through similarity alignment of the conservative transmembrane domainof human MCP-l receptor, mouse MIP-lα receptor and rat IL-8 receptor. the degenerate oligonucleotide homology primers were designed and a cDNA fragment was amplified by RT--PCR. After a new gene sequenceof chemokine receptor supergene-family in GenBank was identified, the new gene full sequence was cloned bya Marathon PCR of the specific primers. Results: Mouse CCR5 full-length cDNA with 2888 bp was cloned,including open reading frame 1065 oligonucleotides and coding 355 amino acids. This gene was a novel member of the β-chemokine receptor supergene-family confirmed by sequence analysis, ligand binding assay andinforming from GenBank. Conclusion: Using homology primers, the novel member of the supergene-familycan be captured. This method is a new cloning strategy and has extensive significance in the molecular cloningof a new gene.

GEOCHEMICAL CHARACTERISTICS OF SUPERGENE ORGANIC MATTER IN HYPERSALINE ENVIRONMENT

The source rocks and crude oils from the Qianjiang Formation (Eocene) in the Jiangban basin have been systematically studied in the present work. Supergene hydrocarboholds are characterized by (ⅰ) high alteration ratio of soluble organic matter over organic carbon and middle ratio of hydrocarbon over organic carbon; (ⅱ) high content of non-hydrocarbon plus asphahene in extracts or crude oils; (ⅲ) sulfur-rich crude oils being an important immature crude oil; (ⅳ) alkane showing high content of phytane, gammacerane and marked even-carbon predominance or odd-carbon predominance; (ⅴ) aromatic biomarkers being distinctly classified into four groups; (ⅵ) pronounced evencarbon predominance in alkyl henzenes. In combination of all geochemical data. it is extrapolated that exploration of immature crude oil in hypersaline environment should be noticed.

A Supergene Differentiation Model for Orebearing Granitic Magma

According to the features of geophysics, experimental petrology, granite geology and geochemistry, the differentiations of ore-bearing granitic magmas are discussed. It is put forward that only the supergene differentiations of ore-bearing granitic magma might exist, instead of the hypogene one of the magma. Based on it, a supergene differentiation model for the ore-bearlng granitic magma is presented.

Discovery and mechanism discussion of supergene micro-ductile shear zone

The strain analysis and micro-structure of deep ductile shear zone (depth】10 km) havebeen studied by many authors, and the forming process of micro-ductile shear zone hasrecently been discussed by some authors. But supergene micro-ductile shear zone(depth【5 km) has rarely been reported. This note reports and discusses the

Classification and mineralization of global lithium deposits and lithium extraction technologies for exogenetic lithium deposits

A reasonable classification of deposits holds great significance for identifying prospecting targets and deploying exploration. The world ’s keen demand for lithium resources has expedited the discovery of numerous novel lithium resources. Given the presence of varied classification criteria for lithium resources presently, this study further ascertained and classified the lithium resources according to their occurrence modes, obtaining 10 types and 5 subtypes of lithium deposits(resources) based on endogenetic and exogenetic factors. As indicated by surveys of Cenozoic exogenetic lithium deposits in China and abroad,the formation and distribution of the deposits are primarily determined by plate collision zones, their primary material sources are linked to the anatectic magmas in the deep oceanic crust, and they were formed primarily during the Miocene and Late Paleogene. The researchers ascertained that these deposits,especially those of the salt lake, geothermal, and volcanic deposit types, are formed by unique slightly acidic magmas, tend to migrate and accumulate toward low-lying areas, and display supernormal enrichment. However, the material sources of lithium deposits(resources) of the Neopaleozoic clay subtype and the deep brine type are yet to be further identified. Given the various types and complex origins of lithium deposits(resources), which were formed due to the interactions of multiple spheres, it is recommended that the mineralization of exogenetic lithium deposits(resources) be investigated by integrating tectono-geochemistry, paleoatmospheric circulation, and salinology. So far, industrialized lithium extraction is primarily achieved in lithium deposits of the salt lake, clay, and hard rock types. The lithium extraction employs different processes, with lithium extraction from salt lake-type lithium deposits proving the most energy-saving and cost-effective.

准噶尔盆地生态环境时空演化及生态环境问题分析(英文)

Geological conditions of Junggar Basin are analyzed in this study,it is located in the northwest arid areas of China with a vulnerable supergene eco-environment.Based on the relationship between underground water and ecological environment,natural geological conditions are combined to classify ecosystem types in the study area,space-time evolution of its eco-environment in three periods is discussed:1990,2000 and 2009;development and utilization of water resources in Junggar Basin as well as its eco-environment evolution laws are taken to analyze problems brought by eco-environment changes,focusing on the following points:A.decreasing area of permanent glacier in mountainous ecosystem,increasing volume of river runoff,reducing capacity of mountainous ecosystem in conserving water resources;B.decreasing underground water,overflowing belt shifting northwards;C.shrinking lake area;D.degrading natural vegetation;E.expanding area of cultivated land and construction land;F.more cultivated land influenced by salinization,showing an increasing trend between 1990 and 2000,maintaining stable between 2000 and 2009,which implies that traditional agricultural irrigation method has brought significant influence on the utilization of water resources,and resulted in the shifting area of salinization.

Research progress on aging of organic pollutants in geosorbents:a review

Geosorbents are the main host of anthropogenic organic pollutants and play a vital role in their fate and transport in the natural environment.Soil and sediment are the most common and abundant geosorbents in the natural environment;their interactions with organic pollutants,especially sorption and desorption processes,have been extensively studied from the perspectives of thermodynamics and kinetics.Recently,the aging of organic pollutants in geosorbents has drawn increased attention,leading to an improved understanding of interactions between organic pollutants and geosorbents and informing remediation criteria.Aging has been deemed important in accurately assessing ecologic and health risks of organic pollutants,and both positive and negative impacts have been reported in studies of natural and artificial sorbents.This paper summarizes recent research progress on organic pollutant aging in geosorbents,including related mechanism research,influence factors,bioavailability assessments,and biological and physicochemical remediation of aged organic pollutants.We also discuss issues in the current research and bring forward suggestions for future study.

A review of major non-sulfide zinc deposits in Iran

The numerous non-sulfide zinc ore deposits were the historical basis for the development of zinc mining in Iran.They include the Mehdiabad,Irankouh and Angouran world-class deposits,as well as the Zarigan and Haft-har deposits.These deposits were formed by supergene oxidation of primary sulfide minerals during the complex interplay of tectonic uplift,karst development,changes in the level of the water table,and weathering.Zn(Pb)carbonates,Zn-hydrosilicates and associated hydrated phases directly replace the primary ore bodies or fill cavities along fractures related to uplift tectonics.Direct replacement of primary sulfides is accompanied by distal precipitation of zinc non-sulfide minerals in cavities or internal sediments filling.The mineralogy of the non-sulfide mineralization in all six deposits is generally complex and consists of smithsonite,hydrozincite,and hemimorphite as the main economic minerals,accompanied by iron and manganese oxy-hydroxides and residual clays.Commonly,non-sulfide minerals in these deposits consist of two types of ore:red zinc ore(RZO),rich in Zn,Fe,Pb-(As)and white zinc ore(WZO),typically with very high zinc grades but low concentrations of iron and lead.Typical minerals of the RZO are Fe-oxyhydroxides,goethite,hematite,hemimorphite,smithsonite and/or hydrozincite and cerussite.Common minerals of the WZO are smithsonite or hydrozincite and only minor amounts of Fe-oxyhydroxides and hemimorphite.

On the Mechanism of Transformation fromPrimary Ores into Oxidized Ores in FinelyDisseminated Gold Deposits

This paper, taking the finely disseminated gold deposits in southwestern Guizhou and northwestern Guangxi as examples, discusses the difference between the occurrence of primary ores and that of oxidized ores, analyzes the occurrence mechanism in terms of crystallochemistry and geochemistry, and especially studies the chemical model for supergene leaching transformation of clay minerals in the two types of ores. This study proposes a new idea for dressing and smelting technology for primary gold ores.

Petrographic and geochemical characterization of weathered materials developed on BIF from the Mamelles iron ore deposit in the Nyong unit, South-West Cameroon

Iron ore deposits hosted by Precambrian banded iron formation(BIF)are the most important source of mineable iron.In Cameroon,they are located in the southern part of the country.This study reports the petrological and geochemical data of iron ores collected from a weathering profile in the Mamelles BIF deposit,SW Cameroon.The profile is composed of three levels which are from the bottom to the top:the saprock,the ferruginous horizon,and the loose horizon.Eight representative iron ore samples(rock fragments and loose clayey material)were collected along the profile and were subjected to petrographic and geochemical analyses.Their mineralogy consists of martite,goethite,quartz,and lesser amounts of hematite,magnetite,kaolinite,and halloysite.The presence of minerals such as kaolinite and goethite in the Mamelles iron ores suggests their supergene origin.Geochemically,the saprock is characterized by high iron content(70.25 wt%Fe_(2)O_(3) t),and low silica(26.38 wt%SiO_(2))and alumina(1.14 wt%Al_(2) O_(3)).The rock fragments collected from the ferruginous horizon display higher Fe2 O3 t(72-76.40 wt%),Al_(2) O_(3)(2.80-5.43 wt%),and lower SiO_(2)(16.70-18.35 wt%)contents,suggesting the leaching of silica during the enrichment process.The loose clayey samples collected from both the ferruginous horizon and the upper loose horizon show lower iron and higher silica contents.When normalized to the underlying BIF saprock,both rock fragments and loose clayey ores display LREE enrichment,suggesting that they formed through supergene processes.Economically,most of the Mamelles iron ores are classified as medium-grade ores and a few display acceptable contents in contaminants.Overall,this petrological and geochemical study of the Mamelles iron ores revealed encouraging results.Given its strategic location near the deep seaport,the deposit should be investigated in more detail for its mining potential.

Reservoir characteristics and genetic differences between the second and fourth members of Sinian Dengying Formation in northern Sichuan Basin and its surrounding areas

This study investigated the characteristics and genesis of reservoirs in the 2^(nd) and 4^(th) members of Sinian Dengying Formation in northern Sichuan and its surrounding areas, on the basis of outcrop, drilling cores and thin section observation and geochemical analysis. The reservoirs of 2^(nd) member are distributed in the middle part of the stratum. The reservoir quality is controlled by supergene karst and the distribution of mound-shoal complex. The bedded elongated isolated algal framework solution-cave and the residual "grape-lace" cave, which are partially filled with multi-stage dolosparite, constituted the main reservoir space of the 2^(nd) member. There is no asphalt distribution in the pores. The pore connectivity is poor, and the porosity and permeability of the reservoir is relatively low. The reservoirs of 4^(th) member were distributed in the upper and top part of the stratum. The reservoir quality is controlled by burial dissolution and the distribution of mound-shoal complex. The bedded algal framework solution-pores or caves, intercrystalline pores and intercrystalline dissolved pores constituted the main reservoir space of the 4^(th) member. It's partially filled with asphalt and quartz, without any dolosparite fillings in the pores and caves. The pore connectivity is good. Most of the 4^(th) member reservoirs had medium-low porosity and low permeability, and, locally, medium-high porosity and medium permeability. Affected by the development of mound-shoal complex and heterogeneous dissolution, the platform margin along Ningqiang, Guangyuan, Jiange and Langzhong is the most favorable region for reservoir development. Deep buried Dengying Formation in the guangyuan and langzhong areas should be the most important hydrocarbon target for the future exploration.

The Machanism of Bacterial Oxidation of Sulphides

The bacteria used in the experiment are Thiobacillus Ferrooxidans separated from acidic mine water in sulphide deposits. The chemoautotrophic bacteria can act directly on sulphides and accelerate the oxidation of sulphides. The experiment shows that the bacteria, as an important microbial factor of gold's supergenous enrichment within the oxidized zones of sulphide deposits, are helpful to dissolve gold and silver in ferric sulphate. In the bacterial oxidation process, the precipitation of goethite is concerned both with the lower activity of ferric ions and with the existence of carbonates in solution. Meanwhile, the acid-resisting and oxidizing ability of the bacteria will certainly lead up to a microbial way of treating the acidic mine water.

Alteration Processes of Paleoproterozoic Manganese Protores of the North Téra:Mineralogy and Geochemistry(West Africa)

The manganese deposit of North Téra is located in the western side of the Diagorou-Darbani greenstone belt in the Niger Liptako Province(Northeastern part of Man Schield,West African Craton).Manganese mineralization bearing rocks are mainly gondites(a kind of garnet-rich quartzite of the spessartine type)whose borders consist of a high concentration of Mn oxide concretions.The methodological approach implemented consisted of a field study followed by a polarizing microscopic analysis in transmitted and reflected light and a geochimical analysis.North Téra gondites originate from Birimian manganese-rich sediments metamorphism in amphibolite facies.The supergene alteration,more or less important,has developed on the protore of gondites,a saprolitic profile whose setting up conditions were recently described in our previous work.The macroscopic analysis of the manganese deposits samples combined with the metallographic microscopic and geochemical analysis confirms that manganese mineralization originated from weathering processes.The first oxide that forms around the garnets is nsutite,while the mesostasis is invaded by pyrolusite with lenses of lithiophorite destabilizing in favor of pyrolusite.In the botryoidal concretions,the latter forms an alternation with the psilomelane rich in Ba(8,101ppm)in the uppermost levels.The abundance diagram shows that the normalize Rare Earths compared to PAAS derived from a plagioclase-rich quartzitic source.This observation is corroborated by a positive anomaly in Eu.Otherwise,the high levels of transition elements(Ni,V,Co and Cr)highlight the involvement of a basic source.The contents of major elements show a significant leaching,with an increase in those of Mn and Al during the increasing weathering.The CIA and PIA indices move in the same direction towards high values leading to the Al2O3 pole on the Al2O3-CaO*+Na2O-K2O diagram.This indicates an increasing alteration along the profile,according to an alteration path comprising plagioclase-smectite-kaolinite and illite to kaolinite.

Geochemistry of Host and Altered Rocks in the Nahran Area, Tarom Zone (NW Iran): Implication for Determining of Mineralization Processes in the Alteration Environment

The Nahran area is located in the Northeast of Zanjan in the Northwest of Iran. This area with 20,000 km2 is part of the Tarom volcanic-plutonic zone which lies between the longitudes 49°7'7.8"E and 36°41'25.74"E near to the Nahran village. The Nahran altered zone is part of large-scale syncline, which is oriented from Sirdan to Altinkosh with an axial length of 9 km. A systematic study of petrographical and geochemical data of Nahran samples reveals they are andesite, trachyandesite to dacite composition and have metaluminous to peraluminous and calc-alkaline affinity. Four alteration zones of propylitic, medium and advanced argillic and silicific zones could be identified in the area. According to our finding, combination of both supergene and hypogene process has an effective role in the development of alteration in the Nahran alteration zone.

“SuperGen Marine”:英国海洋可再生能源研究的加速器

英国拥有特殊的地理位置,其海洋能极其丰富。结合这一优势,英国政府把大力开发利用波浪能和潮汐能做为减少对传统能源的依赖,实现能源结构多元化,减少本国废气排放量的一项重要举措。"SuperGen Marine"是英国政府支持的一项正在进行的大型海洋可再生能源研究项目,其主要目的是增加对海洋能资源的认知和减少海洋能开发利用中的风险。该项目使科研院所与企业紧密协作,覆盖了能源转化、传输和存储等各个方面,其完整的研究模式及方法对我国海洋可再生能源的探索具有非常重要的借鉴意义。

第一届可持续发电与供电国际会议(SUPERGEN2009)征稿通知

第一届可持续发电与供电国际会议(the First International Conference on Sustainable Power Generation and Supply, SUPERGEN 2009)将于2009年4月6-7日在中国江苏省南京市举行。本次会议由英中清洁能源研究协作网(UK-China