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1.
本文在区域地质、水系沉积物测量、土壤测量和高精度磁测等方面对色药异常区的铜找矿前景进行初步分析。利用1∶5万水系沉积物测量编制异常图,发现区内Mo、Cu、Bi、Pb、Zn、Sb、Sn、W、Ag、Hg等元素均有不同规模的异常,且Mo、Cu异常规模较大。通过高精度磁测结果显示区内有3个磁异常,已知铜矿化点均位于磁异常附近。通过土壤测量数据研究元素间的组合关系,推断区内可能的矿床类型与酸性侵入岩有关的斑岩型铜多金属矿。并对区内已发现的1号铜矿化点进行重点研究,表明区内寻找与中酸性侵入岩有关的铜多金属矿具有良好的找矿前景。 相似文献
2.
在研究区1：50万化探扫面圈定异常的基础上,进一步对异常进行了1：10万化探普查和异常查证,圈定综合异常9处,据此进行的矿产普查工作新发现了新疆叶城帕合堡铅锌等一系列矿点,表明该地区是一个找矿新领域。帕合堡铅锌矿位于塔里木地块与羌塘地块接合部,矿体主要赋存于元古界库浪那古群（PtKL）矽卡岩化大理岩中,该套地层富集系数〉1.1的成矿元素有Au、Mo、Pb、Zn。矿体形态复杂,主要呈透镜状、扁豆状、枝叉状等,呈EW向带状分布,总体走向近SN—NE,倾向SE,倾角在30°～70°之间。单矿体地表出露长约73～134m,宽1.2～15.4m,一般宽约5～8m,平均厚度为5.43m,矿体Pb＋Zn品位1.43～12.56×10-2。矿石的自然类型全部为氧化矿,矿石矿物主要由方铅矿、闪锌矿组成,其它有黄铁矿、磁黄铁矿。脉石矿物主要为方解石和白云石。矿体中褐铁矿化蚀变较强。矿床属于与构造破碎有关的沉积变质—中低温热液改造—交代型,成矿时代主要为华里西期。 相似文献
3.
云南金平地区是哀牢山南段重要的Au、Cu多金属矿集区,而Au、Cu为该区主成矿元素的论断和依据缺乏,Au、Cu等成矿元素时空富集配分规律、约束机制尚无论断,该区找矿方向及靶区需进一步明确。本文通过开展1:5万金平县幅水系沉积物测量工作,统计分析全区及各主要地质单元元素含量平均值（X）和相对富集系数（K）等,结合金平地区的地球化学参数特征和元素间组合关系、元素异常与成矿相关性,确定了 Au、Cu、Pb、Zn、Ag为金平地区主成矿元素。通过分析元素地球化学时空分布富集规律,可知金平地区元素地球化学富集配分受时间、空间限制,该地区Au、Cu、Pb、Zn、Ag主成矿元素富集峰期为两个阶段（300～400 Ma、470～485 Ma）,进而确定了奥陶系、志留系、泥盆系、石炭系、二叠系为该地区最具找矿潜力的时代及地层。通过系统研究元素异常与构造、岩浆和成矿的关系,发现区内三家河断裂、马过河断裂、甜竹山断裂对元素富集有明显的影响和控制作用,金平地区元素异常与成矿具有密切相关性。结合金平地区成矿规律和控矿因素等,圈定了12处综合异常,划定了2个找矿预测区,对2个找矿预测区进行找矿潜力分析,指明了找矿方向,提出了进一步工作建议。 相似文献
4.
以三峡地区秭归向斜盆地为研究区,在野外滑坡编图的基础上,选择地形坡度、地层岩性、河流、道路、坡向、坡型结构6个因子参与滑坡敏感性评价,运用GIS空间分析技术,引入频率比模型,分别计算评价因子的贡献率,并进行叠加分析,最终划分为4个敏感性分区。评价结果表明:极高敏感性区面积占21.39%,滑坡发生面积占61.44%;高敏感性分区面积占24.99%,滑坡发生面积占21.67%;中敏感性分区面积占30.66%,滑坡发生面积占13.19%;低敏感性分区面积占22.93%,滑坡发生面积占3.69%。滑坡敏感性面积累计百分比曲线图表明评价结果具有较高的准确度和可靠性。研究成果可为政府部门减灾防灾工程提供科学支持,为滑坡灾害的预测和管理提供科学依据。 相似文献
5.
自西藏区域地质调查大队创建康托组以来,康托组岩石地层单位广泛应用于羌塘地区,普遍认为其时代为新近纪。笔者于丁固—加措地区的康托组地层中采获古近纪轮藻化石Obtusocharasp.,O.lanpingensis,Gyrogonaqinajiangica和部分孢粉化石,并在康托组底部安山岩中获K-Ar年龄65.1～66.5Ma。上述轮藻组合与同位素年龄指示的地层时代为古新世—始新世,据此将测区康托组的时代确定为古近纪。由于测区康托组之上被唢纳湖组或鱼鳞山组角度不整合覆盖,因此康托组时代的确定不仅进一步完善了测区新生代地层系统,还指示测区在康托组与唢纳湖组或鱼鳞山组之间发生了一次强烈的构造运动。 相似文献
6.
针对干旱地区平原绿洲水土资源利用的特点,建立了以农区土壤水为中心的干旱区平原绿洲散耗型水文模型。散耗型模型考虑了水在不同介质和不同形态之间的交换或转化,并重点考虑人类活动如引水灌溉、地下水的开采等对水平衡的影响。模型把研究区划分为河段、泉井、水库湖泊、农区和非农区五类水均衡模块,水均衡模块之间通过地表渠系、地下水侧渗进行水量交换。应用模型可以对研究区农区、非农区各自的蒸发量、农区向非农区地下水迁移量等干旱区主要水分散耗项进行分析。 相似文献
7.
A. Antony Ravindran 《Russian Geology and Geophysics》2013,54(12):1529-1538
Groundwater is a very important component of water resources in coastal aquifers in Thoothukudi. It has been established that the groundwaters in the coastal zone of the Zirconium Complex, Pazhayakayal, Thoothukudi district, Tamilnadu, India, are subjected to wave and tidal impact. The groundwater quality was studied by hydrogeological methods, 2D electrical resistivity imaging (ERI) techniques (six profiles), 11 Wenner vertical electrical sounding (VES), and well log analysis. Also, nine geochemical water samples were taken from the study area. The 2D ERI and VES surveys were carried out using WGMD-4 Ltd., Chennai, resistivity meter, multicore cable, and multielectrodes with Wenner array. The collected resistivity data were interpreted using the Res2DINV software. The research shows that the groundwaters are the result of the paleoriver flow along the Tamirabarani Channel in the western area and of the seawater intrusion in the eastern area. The fresh water is characterized by resistivity of about 10–100 Ohm?m in the study area. The resistivity of 10–50 Ohm?m indicates that the subsurface section is made up of sand, clay, and caliche. Resistivity values of more than 200 Ohm?m are specific to sand dunes. The very low resistivity (<5 Ohm?m) layer might be due to the seawater intrusion in the study area. Six water samples from the well drilled in the coastal area were analyzed, which made it possible to determine the concentrations of major and trace elements in the groundwaters. These data were used to establish the seawater intrusion and coastal environment characteristics in the study area. 相似文献
8.
针对干旱地区平原绿洲水土资源利用的特点,建立了以农区土壤水为中心的干旱区平原绿洲散耗型水文模型。散耗型模型考虑了水在不同介质和不同形态之间的交换或转化,并重点考虑人类活动如引水灌溉、地下水的开采等对水平衡的影响。模型把研究区划分为河段、泉井、水库湖泊、农区和非农区五类水均衡模块,水均衡模块之间通过地表渠系、地下水侧渗进行水量交换。应用模型可以对研究区农区、非农区各自的蒸发量、农区向非农区地下水迁移量等干旱区主要水分散耗项进行分析。 相似文献
9.
朱溪特大型钨铜矿床的发现,使大游山地区W-Cu多金属的成矿潜力受到广泛的关注.本文依据1:5万水系沉积物测量成果,探讨大游山地区成矿元素含量、分布、组合以及综合异常等特征.结果显示,朱溪地区与长源坞地区异常强度高,规模大,元素套合好,朱溪地区为W-Cu多金属找矿远景区,长源坞地区为W-Bi多金属找矿远景区. 相似文献
10.
新疆东天山觉罗塔格地区花岗岩类年代学、构造背景及其成矿作用研究 总被引：34，自引：15，他引：19
东天山觉罗塔格地区岩浆岩非常发育,以花岗岩类分布最为广泛,对其研究还较为薄弱。本文对觉罗塔格地区主要的花岗岩类岩体系统开展了地质特征研究并进行了同位素精确测年,报道了区内16个主要花岗岩类岩体的锆石LA-ICPMS U-Pb年龄：镜儿泉岩体376.9±3.1Ma、西凤山岩体349.0±3.4Ma、石英滩岩体342±11Ma、长条山岩体337.4±2.8Ma、天目岩体320.2±3.1Ma、百灵山岩体317.7±3.7Ma、白石泉岩体303±18Ma、迪坎岩体288.0±2.5Ma、黄山岩体288±17Ma、白山东岩体284.5±4.5Ma、管道岩体284.1±5.8Ma、红石岩体282.7±4.2Ma、陇东岩体276.2±2.5Ma、多头山岩体271.7±5.5Ma、双岔沟岩体252.4±2.9Ma、土墩岩体246.2±2.6Ma,上述定年结果为研究区岩浆活动与区域构造演化及深部过程的关系研究提供了可靠的年代学支持。结合前人已有的部分年代学成果认为,觉罗塔格地区花岗岩类的形成年龄分布在386~230Ma之间,岩浆活动可分为晚泥盆世(386.5~369.5Ma)、早石炭世(349~330Ma)、晚石炭世-晚二叠世(320~252Ma)、早中三叠世(246~230Ma)等4个阶段。前3个阶段岩浆活动具有持续时间逐渐变长、岩浆活动逐渐加剧的特点,并在第三阶段达到顶峰,而第四阶段岩浆活动则明显变弱。花岗岩类岩浆活动在时空分布上表现为,自哈尔里克-大南湖岛弧带→阿奇山-雅满岛弧带→康古尔-黄山韧性剪切带,岩体侵位由早到晚; 自研究区东部→中西部→沿韧性剪切带,岩体侵位由老到新。结合区域构造演化研究成果认为,觉罗塔格地区花岗质岩浆活动与区域构造演化具有很强的耦合关系,花岗岩类在前碰撞阶段、主碰撞阶段、后碰撞阶段、板内阶段等4个构造演化阶段均有发育,与花岗岩类在时间分布上的4个阶段完全对应,其中尤以后碰撞构造演化阶段花岗岩类的分布最广泛、岩浆活动最强烈。觉罗塔格地区与4个阶段花岗岩类有关的成矿作用由早到晚具有无明显矿化→斑岩型铜矿、火山岩型铁矿→韧性剪切带型金矿、夕卡岩型银(铜)矿→斑岩-石英脉型钼矿的演化特点,其中以对应于主碰撞阶段的斑岩型铜矿和后碰撞阶段的韧性剪切带型金矿最为发育。本文系统阐述了东天山觉罗塔格地区中酸性岩体的时空格架、与区域构造演化的耦合、与成矿作用的关系,为北疆地区晚古生代特别是后碰撞背景下的岩浆演化及其成矿关系的研究提供了有力支持。 相似文献
11.
The Chauki, Mandi, Manil colony, Changpur, Khawas and Naghal areas are situated in between the limbs of Hazara Kashmir Syntaxis (HKS). HKS is the part of Himalayan fold and thrust belt that lies in sub-Himalayan domain. Seismically, this is an active zone. Early Miocene to Recent sedimentary rocks are exposed in the area. The stratigraphic units in Kashmir basin are the cover sequence of the Indian plate. These non-marine lithostratigraphic units are molasse deposits formed by the deposition of sediments coming from north carried by the rivers originated from higher Himalayas. Murree Formation of early Miocene age is the oldest rock unit in the studied area. Siwalik Group; Chinji, Nagri, Dhok Pathan and Soan formations of early Miocene to Pliocene and Mirpur Formation of Pleistocene age is exposed. The area is structurally deformed into folds and faults. The Sarda Sarhota syncline, Mandi syncline and Fagosh anticline are major folds in the area. These folds are isoclinal to open in nature, southwest or northeast verging and thrust direction is southwest or northeast. Major reverse faults are Riasi fault and Fagosh fault. The Changpur fault is a normal fault. Primary sedimentary structures present in the area are load cast, ripups and cross bedding. The facing of beds have been marked on the basis of these sedimentary structures. 相似文献
12.
Arsenic concentrations of less than 5 ppb to as large as 1,260 ppb in stream waters and from 5 ppm to 4,000 ppm in stream
sediments were found in the Pedro Dome-Cleary Summit area, Alaska. Waters from three of 20 wells sampled had arsenic concentrations
exceeding the U.S. Public Health Service recommended limit of 50 ppb. The high arsenic levels are a consequence of arsenic
enrichment in the rocks of the area. Placer and lode-gold mining may increase the arsenic content of the waters by exposing
arsenic-containing rocks to surface waters and by increasing the load of arsenic-rich sediments in the streams. Finding these
disturbingly large concentrations of arsenic in the waters of the Fairbanks area was the major result of this work, inasmuch
as a subsequent study (to be published) revealed arsenic concentrations as large as 10 ppm in domestic wells and prompted
an extensive study by Federal and State agencies of the health hazard posed by these arsenic-rich waters. 相似文献
13.
城市土壤环境地球化学研究--以苏州市为例 总被引：4，自引：0，他引：4
通过苏州城市环境地球化学调查工作的实施，对城市土壤环境地球化学研究的工作方法进行了初步研究。结果显示。苏州城市土壤的主要污染区域分布于东南居民生活区、西部工业区、东部木材加工厂集中区及公路干线一带；主要污染物为重金属、有机污染物多环芳烃、有机氯农药等。根据城市自然地理环境、功能分区特点和分布面积大小，确定土壤环境地球化学采样密度和测试项目是城市土壤环境地球化学研究的关键技术。 相似文献
14.
Ayman A. Ahmed 《Arabian Journal of Geosciences》2014,7(8):3069-3083
The occurrence of fluoride in ground water is the focus of the public and has attracted the attention of many scientists all over the world due to its importance in public health. Deficiency or increase of fluoride uptake is considered a public health problem due to the narrow permissible limit which should not exceed 1.5 mg/l according to the World Health Organization (WHO). The range of fluoride tolerance and toxicity is narrow. Deviation from the optimal levels therefore results in dental health effects such as caries and fluorosis. Many studies have found fluorosis to be invariably associated with high concentrations of fluoride in drinking water. Fluorosis is a considerable health problem in many areas of the world including Brazil, China, East Africa, Ghana, India, Kenya, Korea, Malawi, Mexico, Pakistan, South Africa, southeastern Korea, Spain, Sri Lanka, Sudan, Taiwan, Tanzania, and Turkey. Fluoride in groundwater of Quaternary aquifer of the Nile Valley, Egypt, does not gain the attention of the authors in the Nile Valley which makes the public health status of fluoride is not certain. The present work aims at investigating the fluoride concentration of Quaternary groundwater aquifer at Luxor as a representative area of the Nile Valley to be a base line for subsequent studies and criteria for public health. Ground water samples were collected from Quaternary groundwater aquifer at Luxor area, Egypt and analyzed for the purpose of investigating fluoride content. The results showed that fluoride concentration in the study area ranges between 0.113 and 0.452 with an average of 0.242 mg/l. Sources of fluoride in the study area can result from the natural dissolution from fluoride-rich minerals, fertilizers and from groundwater recharge. It is worth mentioning that low fluoride content in the study area is considered a public health threat specially limited growth, fertility, and dental caries. Corrective measures should be taken to avoid the public health impacts of fluoride deficiency at Luxor area as well as similar areas in the Nile Valley. A public health program should be initiated to account for the deficiency of fluoride in groundwater and deal with the other supplementary fluoride sources in food or fluoridation of drinking water supplies. 相似文献
15.
Amit Dharwadkar Prakash K. Shrivastava Hari B. Srivastava 《Journal of the Geological Society of India》2018,92(3):265-280
The Jutulsessen area, can provide a vital clue to the supercontinent assembly of Gondwana Land as it is situated within the Circum East Antarctic Mobile Belt just east of the Penksockett rift marking the divide between the central Dronning Maud Land from the Western Dronning Maud Land. This landmass is dominated by migmatitic quartzo-feldspathic rocks intruded by syn to post-tectonic granites. The work highlights the data from western part cDML area with a view to arrive at a more comprehensive model for the cDML and subsequently to the super continent assembly. Granitic and migmatitic gneisses comprising of amphibolitic and biotite rich enclaves. The gneisses show variations from quartzo-felspathic gneiss to amphibolitic gneiss. The area has witnessed complex geological history involving at different deformational episodes with concomitant metamorphism. The pervasive dominant foliation trends NW-SE with shallow to medium dips towards SW. In the Stabben area, a nonfoliated intrusive syenite-gabbro pluton limits the gneissic exposures. Compositionally, the orthogneisses plot in the monzogranitegranodiorite field where as the mafic dykes/enclaves plot in the basalt-andesite-rhyodacite field. The bulk geochemical characteristics suggest significant crustal contamination. Garnet-biotite Fe-Mg exchange thermometry gives peak metamorphic temperature of 483° C for the gneisses and 628° C for the dioritic enclave within gneisses. A peak metamorphic grade of upper amphibolite to granulite facies is deduced from the mineral assemblages. Widespread anatexis has led to extensive occurrence of migmatites in the area. Recent geochronological studies assign an age of 1170 Ma to 970 Ma for the migmatites/gneisses and an emplacement age of 501 Ma for the Stabben gabbro and syenite. The discriminant plots of the Jutulsessen rocks indicate diverse origin ranging from pre-plate collision to post-collision orogenic tectonic setting. The mafic enclaves/dykes show ocean island arc to MORB affinities. Voluminous addition of juvenile crust during the Pan-African orogeny strongly overprints earlier structures. 相似文献
16.
城口锰矿整装勘查区空白区块全隐伏锰矿体的揭露,标志着城口锰矿整装勘查深部找矿取得重大突破。红籽矿区锰矿呈层状产于陡山沱组顶部,层位稳定。根据岩芯观察、剖面观察、薄片观察、大比例尺地质填图等,展开了岩石学、地层学、沉积学、矿田构造地质学研究,认为红籽矿区菱锰矿层为陡山沱末期深海相向碳酸岩台地过渡时期产物,具台地边缘斜坡沉积特征。首次报道城口锰矿锰质热液运移通道疑似证据以及南大巴山北相区龙潭河组为城口锰矿锰质物源潜力大陆风化源区,红籽矿区矿层中微体藻类降解集合体以及红籽矿区西侧锰质叠层石的发现,再次证实了微生物在成矿过程中的富集作用。锰矿矿石矿物为菱锰矿,矿石结构以微晶、藻鲕为主。综合研究表明沉积相及物质来源控制了矿层沉积,区域叠瓦状-逆冲推覆作用与右型走滑作用控制了矿区锰矿产出形态,红籽矿区B断块、修齐矿区以南至坪坝-修齐断裂之间区块为下一步2000m以浅深部勘探有利区。 相似文献
17.
武夷山地区是一个有色、贵金属、稀有、稀土矿床的重要找矿远景区。通过对该区地质背景、成矿地质条件、矿床富集规律的分析归纳,指出该区以政和-大埔深大断裂为界,其外带（沿海）中生代火山岩大面积出露,内带则常呈一些孤立的火山断陷盆地分布,矿床与火山-侵入岩浆热液作用有密切的成因联系,中生代不同的火山-次火山活动旋回,对该区成矿作用、成矿系列有重要控制作用。 相似文献
18.
19.
萌城矿区位于宁东煤田的最南端,区内由一系列走向NNW或近SN向的褶皱群及与之相伴的断层组成。通过分析各个勘查区的地质特征,总结了矿区构造特征和含煤地层赋存规律：成煤后期的构造控制了本区含煤地层的赋存;延安组呈南北狭长带状分布存向斜及背斜与断层之间相对凹陷的区域内;含煤地层自北而南不仅赋存面积变小,而且含煤性变筹。位于矿区中部的叶庄子小－沙湾子向斜是萌城矿区含煤面积最大的赋煤构造,含煤面积约56km^2。 相似文献
20.
Groundwater quality suitable zones identification: application of GIS,Chittoor area,Andhra Pradesh,India 总被引：3，自引：0，他引：3
Srinivasarao Yammani 《Environmental Geology》2007,53(1):201-210
Due to uneven spatial and temporal distribution of rainfall and lack of sufficient water management technologies, the development
activities of the society are totally depending on groundwater resources. In addition to the prevailing drought-prone conditions,
the improperly treated and unplanned release of effluents of industry, municipal and domestic into the nearby streams and
ponds and the majority usage of groundwater for irrigation are increasing the ionic concentration of the groundwater and making
it more saline. The analytical results of the collected groundwater samples show that the groundwater is alkaline, and sodium
and bicarbonate are the dominant cation and anion, respectively. Gibbs variation diagram shows that the control of the chemistry
of groundwater in the study area is the weathering of granitic gneisses and also the leaching of evaporated and crystallized
ions from the topsoil of the irrigated areas and improperly treated industrial effluent ponds. GIS, a potential tool for facilitating
the generation and use of thematic information, has been applied and analyzed for identification of groundwater quality suitable
zones for domestic and irrigation purposes. 30.06% of the area is with suitable, 67.45% of the area is with moderately suitable
and 2.45% of the area is with unsuitable quality of groundwater for domestic purpose. 46% of the area is with suitable, 53.36%
of the area is with moderately suitable and 0.64% of the area is with unsuitable quality of groundwater for irrigation purpose. 相似文献