共查询到20条相似文献，搜索用时 437 毫秒
1.
对合肥地区浅层地下水取样分析,采用单因子评价法、分类指标评价法和综合评价法对浅层地下水质量进行评价。结果显示:可以直接饮用的地下水资源(Ⅰ类水、Ⅱ类水和Ⅲ类水)占59.3%,经过适当处理可以饮用的地下水资源(Ⅳ类水)占30.5%,不能直接饮用的地下水资源(Ⅴ类水)占10.2%。在地下水评价指标中,挥发性有机指标较好,毒性重金属指标和半挥发性有机指标次之,无机毒理指标和一般化学指标较差。影响地下水质量的化学组分主要为铁、锰、总硬度、溶解性总固体、氟、硫酸盐和钠+钾等无机组分,与人类活动相关的化学组分主要为氨氮、硝酸盐、亚硝酸盐、六价铬、砷、铝、碘、氯化物等无机组分和苯并(a)芘等有机组分。影响地下水质量的原因主要为城市和乡镇工业污水、生活污水排放,农村农药、化肥使用及生活垃圾污染。 相似文献
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利用我国东部平原地下水污染调查评价工作所取得的大量数据, 采用单因子评价法进行地下水质量评价, 采用检出法和超标法进行地下水污染评价.地下水质量评价结果显示, 我国东部主要平原可以直接饮用(Ⅰ~Ⅲ类水)或经适当处理可以饮用(Ⅳ类水)的地下水资源占47.9%, 不能直接饮用的地下水资源(Ⅴ类水)占52.1%;深层地下水质量一般好于浅层地下水.影响地下水质量的天然化学组分主要以锰、铁、氟、碘、总硬度等为主, 人类活动影响则主要体现在"三氮"(NO3-、NH4+、NO2-)、镉、铅和微量有机等组分上.地下水污染评价结果表明, 地下水中"三氮"普遍呈面状污染特征, 重(类)金属呈点污染特征, 尤以铅、砷污染较严重, 有毒有害有机污染呈现"检出率高、超标率低"的特征.我国地下水污染形势严峻, 应该尽快推进全国地下水污染调查评价工作, 组织实施全国地下水污染防治规划, 遏制地下水污染恶化态势, 有效保护我国地下水资源与环境. 相似文献
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为查明阳江温泉度假村及其周边地区地下水环境质量现状及污染物来源,在工作区分别采集地下水、地表水和土壤样品进行检测,并采用单项组分评价法和综合评价法进行地下水环境质量现状评价。结果表明,工作区地下水为V类水,超标项目包括pH、锰、铝、氟化物、总α、细菌总数和总大肠菌群等7项,除总α为放射性外,其它均为常规指标,地下水质量总体为良好～较差,所有监测井的有机指标均未检测出超标值,超标项目主要来源于原生地质环境,地下水水质尚未受到人类活动影响,但地表存在随意弃置的生活垃圾及废水,在长期地表水下渗过程中,仍有污染地下水的可能,应予以重视。 相似文献
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《华北地质》2014,(2)
滦河三角洲是中国北方重要经济区,人口众多,地下水是主要供水水源。在工业和生活污染物排放及农业施用化肥的影响下,地下水遭受一定程度的污染。笔者近年来在滦河三角洲地区开展了野外调查,采集了399组地下水样品,每个样品检测污染指标34项。其中包括,三氮、毒性重金属指标、挥发性有机指标、半挥发性有机指标。本文采用综合污染指数法对滦河三角洲地下水污染状况进行了评价。结果表明:滦河三角洲以工业污染为主,其次为农业污染。浅层地下水以轻微污染为主,未污染比例较低,极重污染的比例相对较高,主要受人类活动影响。深层地下水也有一定程度的污染,但比浅层地下水轻,仅少量的水样点显示轻污染、极重污染,这些样点主要呈点状零星分布。地下水污染的主要因素为"三氮",浅层地下水多受到轻微污染。 相似文献
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《地下水》2020,(3)
昌邑市城区及相关产业园都坐落于潍河冲洪积扇上。2014-2015年进行的昌邑市地下水环境调查项目在该区采集了53组地表水、地下水样品,检测有机污染物90项,地表水中检出的有机污染组分24种,占检测总种类的26. 67%;地下水中检出的有机污染组分14种,占检测总种类的15. 5%;二者均未发现有机物超标现象。地表水有机污染物主要来源于当地企业排污,污水经污水处理厂处理后,有机物种类急剧降低,但很难根除,在远离排污口,有机物的检出种类减少。低强度的污染源对地下水的污染小,地下水的有机污染检出呈点状,具分散性;强度较高且持续的污染会使进入地下水中的有机物呈片状分布,有机物类型为难以降解的三氯甲烷等为主。此项研究能为昌邑市及类似地区产业布局调整、污水排放处理提供科学支撑。 相似文献
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为查明其地下水质量现状,通过对无为地区地下水取样分析,采用地下水单指标及分类指标评价法对无为地区地下水质量进行了评价。评价结果显示,无为地区地下水质量较差,影响地下水质量的天然化学组分主要为铁、锰、铝、总硬度、溶解性总固体、硝酸盐、CODMn、pH、砷等,分析了地下水超标原因,可为该地区地下水资源保护提供借鉴。 相似文献
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在对汶泗河冲洪积平原水文地质条件和污染源现状进行阐述的基础上,对不同含水岩组无机组分指标进行了分析,表明浅层孔隙水和部分地区岩溶裂隙水无机组分含量大幅增高,深层孔隙水无机物含量则变化不大。在有机污染方面,浅层孔隙水有机物检出率26.8%,但含量很低,远未达到饮用水标准限值;岩溶裂隙水有机物检出率46.7%,检出率相对较高,局部地段有机物超标;深层孔隙水有机物基本未检出。该区地下水污染评价结果表明,浅层孔隙水和岩溶裂隙水无机污染呈面状污染特征,且污染程度较重,而有机污染则呈现点状污染特征,且污染程度总体较轻。对研究区地下水污染现状,提出了地下水安全供水对策。 相似文献
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《地学前缘》2021,(5)
掌握区域地下水质量及污染状况,对于地下水污染防治、地下水资源保护与管理具有重要作用,尤其是对西部内陆干旱区地下水资源尤为重要。本研究针对陕西铜川市地下水进行了系统采样,通过分析常规指标、无机毒理指标、微量有机指标,利用"层级阶梯评价方法"进行了地下水质量与污染评价。水质评价表明,2011年铜川市浅层水水质相对较差,可作为饮用水源或经适当处理后可做饮用水源的样品占样品总数的60%,不宜作为生活饮用水源的样品占40%。浅层水质量受天然背景和人类活动的共同影响,主要影响指标为总硬度、NO_3~-、TDS、Mg~(2+)、SO_4~(2-);深层水水质相对较好,所有采样点均可作为饮用水源。深层水主要受天然背景影响,主要影响指标为Fe。污染评价表明,浅层水污染等级为1级、2级、3级、4级的样品分别占样品总数的44%、16%、32%、8%,污染主要分布在金锁关以南至川口以北的漆水河河谷地带;而深层水污染等级全部为1级,尚未受到人类污染影响。相比其他评价方法,层级阶梯评价法在区分天然背景和污染对地下水水质影响方面具有明显优势,结合区域背景分析和现场调查认识,能够成为科学掌握地下水水质及污染状况的有效手段。 相似文献
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贵阳观山湖区至白云区地下水有机污染现状与防治对策 总被引：2，自引：2，他引：0
文章按水文地质条件将全区划分为12个地下水系统,并选择43组控制性水点分丰枯两季进行有机样品采集和测试,在此基础上对研究区地下水中有机污染物的检出、超标、分布及来源均进行了分析。结果显示,参评的86组地下水样品中,有32组检出有机污染物;27种参评有机组分中,10种有机组分存在不同程度的检出,其中,三氯甲烷检出25次,检出率29.07%,其余组分检出率均低于5%;仅有1,2二氯丙烷超标1次,超标率低;区内地下水有机污染物检出浓度较低,超标率低,处于轻度污染阶段;12个系统中,有9个系统发现有机物污染物检出;检出点多分布于工矿企业的下游地段,排污河渠两侧;污染物多来源于中小型工矿企业,以污染物通过落水洞、天窗等进入含水层为主要污染途径;地下水系统排泄区的近源污染多发,危害程度大。针对上述污染特征,提出加强对中小企业污染源的集中管理,加大污水管网建设力度等对策建议。 相似文献
11.
Emily Keeble David I. Whiteside Michael J. Benton 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(2):99-119
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco. 相似文献
12.
Gilles Serge Odin 《Comptes Rendus Geoscience》2002,334(6):409-414
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414. 相似文献
13.
The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts 总被引：4，自引：0，他引：4
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species. 相似文献
14.
Emmanuel Skourtsos Daniel Vachard Alexandra Zambetakis-Lekkas Rossana Martini Louisette Zaninetti 《Comptes Rendus Geoscience》2002,334(12):925-931
Some olistolites reworked in a Tertiary flysch of Mount Parnon (Peloponnesus, Greece) exhibit a Late Permian assemblage, dominated by Paradunbarula (Shindella) shindensis, Hemigordiopsis cf. luquensis and Colaniella aff. minima. This association corresponds to the Late Wuchiapingian (=Late Dzhulfian), a substage whose algae and foraminifera are generally little known. Contemporaneous limestones crop out in the middle part of the Episkopi Formation in Hydra, but they are rather commonly reworked in Mesozoic and Cainozoic sequences. The palaeobiogeographical affinities shared by the foraminiferal markers of Greece, southeastern Pamir, and southern China, are very strong (up to the specific level), and are congruent with the Pangea B reconstructions. To cite this article: E. Skourtsos et al., C. R. Geoscience 334 (2002) 925–931. 相似文献
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正20141596 Liu Yunhuan(School of Earth Sciences and Resources,Chang’an University,Xi’an 710054,China);Shao Tiequan Early Cambrian Quadrapyrgites Fossils of Xixiang Boita in Southern Shaanxi Province(Journal of Earth Sciences and Environment,ISSN1672-6561,CN61-1423/P,35(3),2013,p.39-43,3 illus.,20 refs.) 相似文献
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正20141719 Chen Zhijun(State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China);Chen Jianguo Automated Batch Mapping Solution for Serial Maps:A Case Study of Exploration Geochemistry Maps(Journal of Geology,ISSN1674-3636,CN32-1796/P,37(3),2013,p.456-464,2 illus.,2 tables,10 refs.) 相似文献
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正20140962 Chen Fenning(Xi’an Institute of Geology and Mineral Resources,Xi’an710054,China);Chen Ruiming Late Miocene-Early Pleistocene Ostracoda Fauna of Gyirong Basin,Southern Tibet(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,87(6),2013,p.872-886,6illus.,56refs.) 相似文献
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正1.IGNEOUS PETROLOGY20142008Cai Jinhui(Wuhan Center,China Geological Survey,Wuhan 430205,China);Liu Wei Zircon U-Pb Geochronology and Mineralization Significance of Granodiorites from Fuzichong Pb-Zn Deposit,Guangxi,South China(Geology and Mineral Resources of South China,ISSN1007-3701,CN42-1417/P,29(4),2013,p.271-281,7illus., 相似文献
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正20141205Cheng Weiming(State Key Laboratory of Resources and Environmental Information System,Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China);Xia Yao Regional Hazard Assessment of Disaster Environment for Debris Flows:Taking Jundu Mountain,Beijing as an 相似文献
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正20141266Fan Chaoyan(Guangdong Provincial Key Laboratory of Mineral Resources and Geological Processes,Guangzhou 510275,China);Wang Zhenghai On Error Analysis and Correction Method of Measured Strata Section with Wire Projection Method(Journal of 相似文献