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1.
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
2.
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
3.
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
4.
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
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现代湖盆源-汇系统分析,可为古代源-汇系统研究提供参考依据.将云南洱海现代湖盆源-汇系统划分为西（S2S-W）、东（S2S-E）、北岸（S2S-N）3个独立的源-汇系统,S2S-E物源区母岩主要为碳酸盐岩,沉积体数量少、规模小（ < 10 km2）;S2S-W物源区母岩主要为变质岩及少量花岗岩、碳酸盐岩,沉积体数量多、规模大（> 40 km2）,相互叠置、连片分布;S2S-N为轴向物源型源-汇系统,母岩主要为碎屑岩,沉积物供应充足,形成大型沉积体.研究表明,同一盆地（洼陷）内可存在多个源-汇系统,由于母岩类型、构造活动、古地貌等因素的影响,可造成不同源-汇系统的流域面积、沉积区面积及沉积响应存在差异,在古代源-汇系统研究中需重视不同源-汇系统之间的差异性研究. 相似文献
6.
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
7.
吐哈盆地南缘白咀山至迪哈尔地区中侏罗统西山窑组地质地球化学特征与铀成矿有利层位 总被引：4，自引：0，他引：4
本文在层序地层学研究的基础上 ,对吐哈盆地南缘白咀山至迪哈尔地区中侏罗统西山窑组同一小层序层位的原生砂体进行了铀、钍、有机炭、常量元素地球化学以及砂体产出规模、渗透性、层间氧化带特征的研究 ,并与十红滩地区对比后认为 ,迪哈尔地区小层序地层层位LPS2 、EPS3、LPS4 及白咀山地区的LPS3、LPS4 均是砂岩型铀矿形成的有利层位。其中 ,迪哈尔LPS2 及白咀山LPS3小层序层位是主要的有利层位。 相似文献
8.
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
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10.
Studies of groundwater chemistry in the Koilsagar project area of Andhra Pradesh indicate that the waters are sodium bicarbonate, sodium chloride, mixed cationic-mixed anionic, mixed cationic Na dominating bicarbonate, and mixed cationic Ca dominating bicarbonate types. Of them, sodium bicarbonate and mixed cationic Mg dominating bicarbonate types of waters are more prevalent.Isocone mapping of specific conductance indicates that the ionic concentration increases from east to west in the area. Graphical treatment of chemical data reveals that, in general, the area has basic water, whereas the left flank canal area is dominated by secondary alkaline water, and Pallamarri and Pedda Rajmur villages have strongly acidic waters. Ion-exchange studies show that cation-anion exchanges exist all over the area except for two places, which have a base exchange hardened type of water.Graphical representation further shows that most of the area has medium salinity-low sodium (C2S1) water useful for irrigation purposes. High salinity-low sodium (C3S1) and high salinity-medium sodium (C3S2) waters are present in some areas, which need adequate drainage to overcome the salinity problem. 相似文献
11.
通过收集福建省龙岩苏邦矿区三个井田的地质资料,在综合分析地层及构造的基础上,对矿区的断裂构造的成因采用滑脱构造的理论,总结出区内四种断裂构造的成因,并进行了断裂构造期次分析,对矿区构造规律的研究具有一定意义. 相似文献
12.
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
13.
新疆克拉玛依地区出露的早古生代蛇绿混杂岩带规模巨大,岩石单元出露齐全。白碱滩地区的地幔橄榄岩相对比较新鲜,单斜辉石、斜方辉石、尖晶石和橄榄石保存完好。研究表明,白碱滩蛇绿岩就位前,地幔岩发生了大于50km的快速隆升,且没有发生部分熔融。百口泉地区发现的地幔岩普遍遭受了改造,辉石多发生了强烈蚀变(透闪石化),但尖晶石和橄榄石保存较好。百口泉地区出露的地幔岩和白碱滩地幔岩的矿物组成基本一致,表明它们属于同一蛇绿混杂岩带。百口泉蛇绿岩剖面的揭露,将该蛇绿混杂岩带的范围向NE方向延伸了35km。 相似文献
14.
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
15.
H. S. Goldie 《Environmental Geology》1996,28(3):128-136
Varied, well-developed limestone pavements are well exposed over an extensive area of the Carboniferous limestone outcrop
of the Orton-Asby escarpment, Cumbria. This area is the largest expanse of limestone pavements outside the well-known Ingleborough
karst of Yorkshire, and the National Nature Reserve at Great Asby Scar includes the best developed and least damaged landforms
of the whole area, most of which is now protected by Limestone Pavement Orders.
Received: 1 June 1995 · Accepted: 4 December 1995 相似文献
16.
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
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Text, talk, things, and the subpolitics of performing place 总被引：1，自引：0，他引：1
This article tells the story of how a group of Dutch and Belgian citizens organized themselves to promote an area that they valued, to put it on the map, to raise awareness about its qualities, and to protect it from urban and industrial development. Our theoretical perspective focuses on the performative and political aspects of this place-making process and the discursive and material practices involved. We connect this to Beck’s concept of subpolitics.Our findings show how the group performed this place not only through text and talk - giving the area a name, using their knowledge and expertise to raise awareness about its values, lobbying and cooperating with decision-makers -, but also through things - installing art objects and information signs that articulate certain characteristics and values of the area. Our findings demonstrate the struggles involved in these performances. The group involved multiple perspectives on what the important values and characteristics of the area are and on what strategies would work best in trying to influence decision-making and protect the area. However, the use of expertise as the main strategy to gain influence excluded the more critical and activist strategies and privileging archaeological and historical values and characteristics came at the expense of attention on agricultural and natural values.Our findings make clear that performing place cannot be taken to be homogeneous and that it inevitably involves multiple perspectives and demands. The struggles, power relations and dynamics of inclusion and exclusion that this multiplicity implicates reveal a form of sub-politics that involves both politicization and depoliticization. Also, it is a form of subpolitics that is more diverse and ambiguous than Beck’s conceptualization presupposes by its emphasis on the role of outsiders as a homogeneous group. 相似文献
20.
Cheng-fan Li Di Shen Jiang-shan Dong Jing-yuan Yin Jun-juan Zhao Dan Xue 《Arabian Journal of Geosciences》2014,7(10):3961-3971
This paper investigates the urban heat island (UHI) characteristics of Shanghai, China, during 1981–2010 using Landsat thematic mapper/multispectral scanner and moderate-resolution imaging spectroradiometer satellite data from the perspectives of time and space, with further analysis of the landscape pattern, the urban heat island effect ratio, and formative factors. The results show the following: (1) From the interannual variation, the secondary-medium temperature area and the medium temperature area are the main bodies of Shanghai UHI, accounting for 67.16–83.69 % of the total area, and have a rising trend over time. (2) From the landscape pattern, the secondary-medium temperature area and the medium temperature area have a dominant position over the whole UHI landscape pattern of Shanghai; the relatively high-temperature area gradually decreases, and its dominance over the whole UHI landscape pattern declines. (3) From the spatial distribution, the pattern in which the urban area initially had complete domination has gradually transformed to become primarily urban area centered and other construction land supplemented with rapid urbanization. Rapid increase of the green land in the urban area has to some extent reduced the UHI characteristics of the Shanghai area in recent years. 相似文献