检索结果-南通市图书馆

hydrothermal alteration of the surface volcanic rocks at the Acoculco geothermal field,Mexico:a multi-parametric approach

引用

Acta Geochimica 2024年第6期43卷 1037-1053页

作者： America Yosiris García-Soto Kailasa Pandarinath ESantoyo Eduardo Gonzalez-Partida Instituto de Energías Renovables Universidad Nacional Autónoma de MéxicoPriv.Xochicalco s/no.Col.CentroApartado Postal 3462580 TemixcoMorelosMexico Centro de Geociencias UNAMApartado Postal 1-74276001 QuerétaroQuerétaroMexico

The studies on hydrothermal alteration-induced eff ects in surface and subsurface rocks provide useful information in the characterization and exploitation of a geothermal ***,these studies are based on traditional,and reliable methods like petrography(primary and secondary minerals,and grade of alteration),and geochemistry(mobility of elements,changes in mass and concentration of elements,and fluid inclusions).Recently,apart from these established methods,some methods based on the geochemical(Chemical Index of alteration,CIA;Weathering Index of Parkar,WIP;Loss on Ignition,LOI;and Sulfur,S)and rock magnetic properties(magnetic susceptibility,χlf;and percentage frequency-dependent susceptibility,χfd%)are also being applied in the identification of whether a rock is an altered or a fresh *** Acoculco Geothermal Field(AGF),Mexico,is characterized by high temperature and very low permeability,and it is considered a promissory Enhanced Geothermal *** following changes are observed in the rocks as a result of an increase in hydrothermal alteration:(1)an increase in CIA,LOI,and S values,and a decrease in WIP;(2)an increase in quartz and quartz polymorph minerals(silicification),and clay minerals(argillization);and(3)decrease inχlf *** AGF,the most altered surface acid rocks are characterized by entirely quartz and its polymorphs,and clay *** present study also indicates the applicability of the binary plots of major elements(felsic vs mafic component)and rock magnetic parameters(χlf vs.χfd%).The rock withχfd%value of 2-10 andχlf valuehydrothermally altered rocks during the initial stage of geothermal exploration.

关键词： Geothermal fields hydrothermal alteration Surface rocks Magnetic susceptibility alteration indices

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Application of Spectral Angle Mapper Classification to Discriminate hydrothermal alteration in Southwest Birjand, Iran, Using Advanced Spaceborne Thermal Emission and Reflection Radiometer Image Processing

引用

Acta Geologica Sinica(English Edition) 2012年第5期86卷 1289-1296页

作者： Maryam ABDI Mohammd H. KARIMPOUR Department of Geology Ferdowsi University of Mashhad P.O. Box 91775-1436 Mashhad Iran Research Center for Ore Deposit of Eastern Iran Ferdowsi University of Mashhad Mashhad Iran

The purpose of this study is to evaluate the Spectral Angle Mapper （SAM） classification method for determining the optimum threshold （maximum spectral angle） to unveil the hydrothermal mineral assemblages related to mineral deposits. The study area indicates good potential for Cu-Au porphyry, epithermal gold deposits and hydrothermal alteration well developed in arid and semiarid climates, which makes this region significant for Advanced Spaceborne Thermal Emission and Reflection Radiometer （ASTER） image processing analysis. Given that achieving an acceptable mineral mapping requires knowing the alteration patterns, petrochemistry and petrogenesis of the igneous rocks while considering the effect of weathering, overprinting of supergene alteration, overprinting of hypogene alteration and host rock spectral mixing, SAM classification was implemented for argillic, sericitic, propylitic, alunitization, silicification and iron oxide zones of six previously known mineral deposits： Maherabad, a Cu-Au porphyry system; Sheikhabad, an upper part of Cu-Au porphyry system; Khoonik, an Intrusion related Au system; Barmazid, a low sulfidation epithermal system; Khopik, a Cu-Au porphyry system; and Hanish, an epithermal Au system. Thus, the investigation showed that although the whole alteration zones are affected by mixing, it is also possible to produce a favorable hydrothermal mineral map by such complementary data as petrology, petrochemistry and alteration patterns.

关键词： hydrothermal alteration Spectral Angle Mapper Advanced Spaceborne Thermal Emission and Reflection Radiometer image process Iran

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

hydrothermal alteration of chevkinite-(Ce) in the Shuiquangou syenitic intrusion,northern China

Hydrothermal alteration of chevkinite-(Ce) in the Shuiquango...

引用

中国科学院地质与地球物理研究所2006学术年会

作者： Jiang,Neng Key Laboratory for Mineral Resources Research,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China

A rare-earth iron titanosilicate mineral closely associated with amphibole was found in two altered syenite samples from the Shuiquangou syenitic *** on electron microprobe analyses,the mineral is chevkinite-(Ce).The mineral is altered and mantled by a corona of allanite(?)ilmenite(?)titanite(?)epidote(?)*** balance calculations reveal that the former chevkinite was replaced directly by an allanite and ilmenite association (allanite(?)ilmenite zone) in the inner part of the corona *** appears that during the replacement,Si and Ti were immobile,whereas Al,Fe,Mn,Mg and Ca were externally supplied and a proportion of REE and Th were transferred out of the former *** released REE and Th become incorporated in allanite and titanite in the allanite(?)ilmenite(?)titanite mantle where allanite contains higher Nd,Sm and Y but lower La and Ce than that in the allanite(?)ilmenite zone,suggesting that redistribution of these elements took place and the mobility of Nd,Sm and Y is enhanced during hydrothermal alteration.

关键词： Chevkinite-(Ce) Corona system hydrothermal alteration Mobilization

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Three-dimensional geological modelling and direction of hydrothermal alteration of Horne deposit, Blake River Group, Quebec, Canada

引用

Global Geology 2021年第1期24卷 15-22页

作者： TIAN Liya YU Yunliang XU Haibo College of Earth Sciences Jilin UniversityChangchun 130061China

The Horne deposit with rich Cu and Au in Noranda region of Black River Group in Quebec has high economic *** researches on Horne deposit are mostly based on two-dimensional maps and statistical *** is hard to reflect the spatial structure and characteristics of Horne orebody *** this paper,GIS was used to digitize the mining plan-view maps at different depths,stope maps,the boundary of the massive sulfide in drilling trajectories as well as the grade data of Au and Cu of Horne ***,the authors established the grade attribute *** the three-dimensional(3D)geological model and grade attribute model of Horne orebody were established by Geological Object Computer Aided Design(GOCAD).Positions of two vents and directions of hydrothermal alteration in Horne deposit were inferred based on the property of the major fault,characteristics of hydrothermal alteration,the enrichment morphology and spatial distribution of high-grade Cu in the Cu attribute model.

关键词： Horne deposit massive sulfide three-dimensional geological modeling hydrothermal alteration

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

ASTER Data Processing by Discrete Wavelets Transform and Band Ratio Techniques for the Identification of Lineaments and hydrothermal alteration Zones in Poli, North Cameroon

引用

Journal of Geoscience and Environment Protection 2023年第9期11卷 216-232页

作者： Mohamadou Ahamadou May Nome Stella Meying Arsène School of Geology and Mining Engineering University of Ngaoundéré Ngaoundéré Cameroon Centre for Geological and Mining Research Garoua Cameroon

The aim of this study is to carry out hydrothermal alteration mapping and structural mapping using ASTER images in order to identify indices that could guide mining exploration work in the Poli area and its surroundings. To achieve this, the ASTER images were first preprocessed to correct atmospheric effects and remove vegetation influence. Secondly, a lineament mapping was conducted by applying Discrete Wavelet Transform (DWT) algorithms to the First Principal Component Analysis (PCA1) of Visible Near-Infrared (VNIR) and Shortwave Infrared (SWIR) bands. Lastly, band ratio methods were applied to the VNIR, SWIR, and Thermal Infrared (TIR) bands to determine indices of iron oxides/hydroxides (hematite and limonite), hydroxyl-bearing minerals (chlorite, epidote, and muscovite), and the quartz index. The results obtained showed that the lineaments were mainly oriented NE-SW, ENE-WSW, and E-W, with NE-SW being the most predominant direction. Concerning hydrothermal alteration, the identified indices covered almost the entire study area and showed a strong correlation with lithological data. Overlaying the obtained lineaments with the hydrothermal alteration indices revealed a significant correlation between existing mining indices and those observed in the field. Mineralized zones generally coincided with areas of high lineament density exhibiting significant hydrothermal alteration. Based on the correlation between existing mining indices and the results of hydrothermal and structural mapping, the results obtained can then be used as a reference document for any mining exploration in the study area.

关键词： Discrete Wavelets Transform Band Ratio Lineaments hydrothermal alteration

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

The Activity of Major Faults and the hydrothermal alteration Zone at Tianchi Volcano of Changbaishan

引用

Earthquake Research Advances 2004年第3期000卷 45-54页

作者： Liu Mingjun 1), Gu Menglin 1), Sun Zhenguo 1), Wei Haiquan 2) and Jin Bolu 3) 1) Geophysical Exploration Center, CEA, Zhengzhou 450002, China 2) Institute of Geology, CEA, Beijing 100029, China 3) The No.6 Geological Survey of Geological and Mineral Resource Administration of Jilin Province, Yanji 133001, Jilin, China Geophysical Exploration Center CEA Zhengzhou 450002China Institute of Geology CEA Beijing 100029China The No.6 Geological Survey of Geological and Mineral Resource Administration of Jilin Province Yanji 133001JilinChina

It is found by field investigation that the near horizontal top surface of the brown or brick-red hydrothermal alteration zone varies obviously in elevation at different sections of the same layer on the caldera’s inner wall of Tianchi, with that at the north section near the Tianwen Peak about 110 m higher than that at the south near the Jiangjun Peak in Korea. The top surface of the hydrothermal alteration zone can be taken as key horizon to tectonic movement. The difference indicates that the total uplift height of the NW wall of the Liudaogou-Tianchi-Jingfengshan fault, the principal fault trending NE at Tianchi, is bigger than that of the SE wall ever since the occurrence of hydrothermal alteration. This also explains why the topography in the northwest side of Tianchi is steeper and with more developed river system than in the southeast. The uplifting of the northeastern wall is bigger than that of the southwest along the principal NW-trend fault, namely, the Baishanzhen-Tianchi-Jince fault. It is observed from characters of hydrothermal alteration and the palaeoresiduum, that the recent vertical movement rate along the principal NE-trend fault is larger than that of the principal NW-trend fault. The two faults intersect at Tianchi, dividing the volcano into 4 blocks, with the uplift magnitudes decreasing successively in the order of the north, the west, the east and the south block. The biggest uplift of the north block corresponds well to the shallow magma batch in the north of Tianchi observed by DSS and telluric electromagnetic sounding, and etc. and they may be related with the causes.

关键词： Tianchi volcano Major fault Caldera’s inner wall hydrothermal alteration Different uplift

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

The Activity of Major Faults and the hydrothermal alteration Zone at Tianchi Volcano of Changbaishan

引用

Earthquake Research in China 2004年第3期18卷 253-262页

作者： LiuMingjun GuMenglin SunZhenguo WeiHaiquan JinBolu GeophysicalExplorationCenter CEAZhengzhou450002China InstituteofGeology CEABeijing100029China TheNo.6GeologlcalSurveyofGeologicalandMineralResourceAdministrationofJilinProvince Yanji133001JilinChina

关键词： Tianchi volcano Major fault Caldera's inner wall hydrothermal alteration Different uplift

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Application of Airborne Geophysical and ASTER Data for hydrothermal alteration Mapping in the Sar-Kuh Porphyry Copper Area, Kerman Province, Iran

引用

Open Journal of Geology 2016年第10期6卷 1257-1268页

作者： Mehdi Honarmand Department of Ecology Institute of Science and High Technology and Environmental Sciences Graduate University of Advanced Technology Kerman Iran

Known deposits are appropriate sites for investigating significant exploratory keys that could be helpful in mineral exploration in corresponding regions or similar areas. This study was performed to delineate hydrothermal alteration model and some geophysical characteristics of the SarKuh porphyry copper deposit located within the southern part of the central Iranian Cenozoic magmatic belt (CICMB). Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) images have been used to produce hydrothermal alteration map using a fractal-aided spectral angle mapper (SAM) method. Airborne data were used to study magnetic-radiometric properties of the deposit. Image processing of ASTER images and laboratory studies proved the presence of two types of phyllic ale ration called intense and weak phyllic based on abundance of sericite mineral. It realized that radiometric anomalies of 40K, eTh and eU are limited to boundary of phyllic zone. Radiometric ratios e.g. eTh/40K were good enough to enhance phyllic zone.

关键词： Porphyry Copper Deposit hydrothermal alteration ARTER SAM Airborne Geophysics

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geology and hydrothermal alteration of the Duobuza Gold-Rich Porphyry Copper District in the Bangongco Metallogenetic Belt,Northwestern Tibet

Geology and Hydrothermal Alteration of the Duobuza Gold-Rich...

引用

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： Guangming LI Jinxiang LI Kezhang QIN Ji Duo Tianping ZHANG Bo XIAO Junxing ZHAO Key Laboratory of Mineral Resources Institute of Geology and GeophysicsCASBeijing

The Duobuza gold-rich porphyry copper district is located in the Bangongco metallogenetic belt in the Bangongco-Nujiang suture zone south of the Qiangtang *** main gold-rich porphyry copper deposits (Duobuza and Bolong) and an occurrence(135 Line) were discovered in the district The porphyry-type mineralization is associated with three Early Cretaceous ore-bearing granodiorite porphyries at Duobuza,135 Line and Bolong,and is hosted by volcanic and sedimentary rocks of the Middle Jurassic Yanshiping Formation and intermediate-acidic volcanic rocks of the Early Cretaceous Meiriqie *** emplacement and isometric distribution of three ore-forming porphyries is explained as multi-centered mineralization generated from the same magma *** hydrothermal alteration occurs in the porphyries and at the contact zone with wall *** main hypogene alteration zones are distinguished at ***-stage alteration is dominated by potassic alteration with extensive secondary biotite,K-feldspar and *** alteration zone includes dense magnetite and quartz-magnetite veinlets,in which Cu-Fe-bearing sulfides are *** alteration occurs in the host basic volcanic *** chloritization-silicification with quartz-chalcopyrite or quartz-molybdenite veinlets superimposes on the potassic ***-stage argillic alteration overlaps on all the ear Her *** alteration stage is characterized by destruction of feldspar to form illite,dickite and kaolinite,with accompanying veinlets of quartz + chalcopyrite + pyrite and quartz + pyrite assemblages. Cu coexists with Au,which indicates their simultaneous *** balance calculations show that ore-forming elements are strongly enriched during the above-mentioned three alteration stages.

关键词： Bangongco metallogenetic belt Duobuza porphyry copper district hydrothermal alteration mass balance mineralization northwestern Tibet

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Resolving impact volatilization and condensation from target rock mixing and hydrothermal overprinting within the Chicxulub impact structure

引用

Geoscience Frontiers 2022年第5期13卷 16-31页

作者： Thomas Déhais Stepan M.Chernonozhkin Pim Kaskes Sietze J.de Graaff Vinciane Debaille Frank Vanhaecke Philippe Claeys Steven Goderis Analytical Environmental and Geo-ChemistryVrije Universiteit BrusselBrusselsBelgium Laboratoire G-Time UniversitécLibre de BruxellesBrusselsBelgium Department of Chemistry Atomic&Mass SpectrometryGhent UniversityGhentBelgium

This work presents isotopic data for the non-traditional isotope systems Fe,Cu,and Zn on a set of Chicxulub impactites and target lithologies with the aim of better documenting the dynamic processes taking place during hypervelocity impact events,as well as those affecting impact structures during the post-impact *** focus lies on material from the recent IODP-ICDP Expedition 364 Hole M0077A drill core obtained from the offshore Chicxulub peak *** ejecta blanket samples from the UNAM 5 and 7 cores were used to compare the crater lithologies with those outside of the impact *** datasets of bulk Fe,Cu,and Zn isotope ratios are coupled with petrographic observations and bulk major and trace element compositions to disentangle equilibrium isotope fractionation effects from kinetic *** observed Fe and Cu isotopic signatures,with δ^(56/54)Fe ranging from0.95‰to 0.58‰and δ^(65/63)Cu from0.73‰to 0.14‰,mostly reflect felsic,mafic,and carbonate target lithology mixing and secondary sulfide mineral formation,the latter associated to the extensive and long-lived(>105 years)hydrothermal system within Chicxulub *** the other hand,the stable Zn isotope ratios provide evidence for volatility-governed isotopic *** heavier Zn isotopic compositions observed for the uppermost part of the impactite sequence and a metamorphic clast(δ^(66/64)Zn of up to 0.80‰and 0.87‰,respectively)relative to most basement lithologies and impact melt rock units indicate partial vaporization of Zn,comparable to what has been observed for Cretaceous-Paleogene boundary layer sediments around the world,as well as for tektites from various strewn *** contrast to previous work,our data indicate that an isotopically light Zn reservoir(δ^(66/64)Zn down to0.49‰),of which the existence has previously been suggested based on mass balance considerations,may reside within the upper impact melt rock(UIM)*** observation is restricted to a few UIM sampl

关键词： Chicxulub impact structure Non-traditional stable isotopes Impact volatilization Impact condensation hydrothermal alteration Target lithology mixing

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：