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101.
AbstractThe objectives of this study were to discover the relationship between variables in a water reservoir and the hydrochemical variations related to acid mine drainage (AMD), and to describe the horizontal stratification related to vertical salinity and variations in metals present in the region. The information obtained may be used for establishing risk evaluation criteria and to design future remediation strategies, which could be useful for new dams. The hydrochemical characterization was based on a sampling campaign performed in October 2011. A total of 28 samples, at 1-m-deep intervals, were obtained. The hydrogeochemical study of the polluted reservoir shows that the dilution effect is not sufficient to neutralize AMD contributions from mining activity. Sampling carried out from the surface water to the deepest points reveals stratification of the reservoir that allows it to be included in the group of monomictic and holomitic lakes.
Editor D. Koutsoyiannis; Associate editor M.D. Fidelibus 相似文献
102.
有证据表明,个旧矿区矿产除与花岗岩密切相关外,基性火山或喷流沉积作用也较明显,变基性火山岩型铜矿的发现及研究增添不少理由。该型Cu矿层状、似层状,赋存于个旧组下段卡房段,矿层多,具同生沉积构造,从而对个旧矿区成矿理论增添新看法。 相似文献
103.
渤海油田古近系三角洲沉积发育巨厚(大于100 m)的砂岩和砾岩储层,储层横向变化快,内部非均质性强,地震预测难题大。文章针对此类问题,提出一种基于厚度解释量版的砂砾岩定量表征方法。根据已有钻井资料建立井点处地质模型,结合已有地质资料分析储层可能的变化形式,形成地质模型库,对地质模型库进行正演获得相应的正演地震资料库,然后提取正演地震资料的反射振幅属性,建立不同砂砾岩变化形式下的厚度解释量版,最后提取实际地震资料的反射振幅属性,将其投射到厚度解释量版上,实现对巨厚砂砾岩储层的定量表征。该方法克服了常规地震反演、地震属性等方法难以有效刻画巨厚砂砾岩储层的难题,实现了对具有干涉效应的巨厚砂砾岩储层的厚度及其内部变化的精确定量表征。 相似文献
104.
Mustafa Evren Ersahin Recep Kaan Dereli Hale Ozgun Berivan Gunes Donmez Ismail Koyuncu Mahmut Altinbas Izzet Ozturk 《洁净——土壤、空气、水》2011,39(6):543-548
Baker's yeast industry has significant effects on environment due to significant water consumption and high strength wastewater production. Effluents from baker's yeast industry are characterized by high concentrations of biological oxygen demand (BOD5), chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN), total dissolved solids (TDS), sulfate, and dark brown color. The aim of this study is to provide a detailed quantitative and qualitative identification and characterization of the wastewater sources from different processes of a baker's yeast industry. It is identified that the most polluted wastewater components of the facility are coming from rotary drum filter and evaporation process. However, the highest pollution loads is identified as tank and equipment cleaning effluent due to very high flow rate from this source. The efforts should be on the way to minimize the water usage for the tank and equipment cleaning process, and to recycle less polluted waste streams back to the process. 相似文献
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107.
A.J. Hobday J.W. YoungC. Moeseneder J.M. Dambacher 《Deep Sea Research Part II: Topical Studies in Oceanography》2011,58(5):734-745
Although many species in the pelagic ocean are widespread, they are not randomly distributed. These species may have associations with particular water masses or habitats, but to best understand patterns in the ocean, these habitats must be identified. Previous efforts have produced static or seasonal climatologies, which still represent smearing over habitats. The Eastern Tuna and Billfish Longline Fishery (ETBF) targets a range of high trophic level species in oceanic waters off eastern Australia. In this study, dynamic ocean habitats in the region were identified for each month based on cluster analysis of five oceanographic variables averaged at a monthly time scale and a spatial scale of 0.5° for the period 1995-2006. A total of seven persistent habitats were identified off eastern Australia with intra and interannual variation in size and location, indicating the importance of spatial and temporal variation in the dynamics of the region. The degree to which these dynamic habitats were distinguished was tested using (i) stable isotope analysis of top fish predators caught in the region and (ii) estimates of variation in estimated abundance generated from catch data from the fishery. More precise estimates (measured as lower total CV) of isotopic values from swordfish (Xiphias gladius), yellowfin tuna (Thunnus albacares) and albacore (Thunnus alalunga) were obtained for 4 of 6 isotope comparisons using the dynamic habitat groupings, which indicate that stratifying by pelagic habitat improved precision. Dynamic habitats produced more precise abundance estimates for 7 of 8 large pelagic species examined, with an average reduction in total CV of 19% compared to when abundance was estimated based on static habitat stratification. These findings could be used to guide development of effective monitoring strategies that can distinguish patterns due to environmental variation, and in the longer term, climate change. 相似文献
108.
Development of technologies for site characterization has grown at a faster pace compared to the development of decision-making methods required for the assimilation of inferences they generate. In the case of geophysical surveying, such dephase adds to the dependency on the use of expert's judgment in the interpretation of geophysical mappings. A systematic assimilation of this type of geo-surveying evidence is required, in particular for the integration of spatial geomorphological information (i.e., stratigraphy), characterized from different geophysical methods. This paper presents a methodology to address this challenge by the use of a probabilistic approach. A set of synthetic geophysical mappings are used to illustrate the applicability of the proposed methodology and its potential extrapolation to other scientific imaging disciplines. 相似文献
109.
截止目前云南已知油页岩矿点20余处,资源量1.58亿吨,折合页岩油550万吨;含油页岩岩系自寒武系下统—新近系上新统,主要赋存于下寒武统、中泥盆统近底部、中侏罗统、上白垩统和新近系中新统、上新统等层位.除下古生界为滨海—海湾泻湖相和滨外平原相外,其他则为内陆湖泊相.大部分矿点油页岩厚度可以达到最低可采厚度1m以上,含油率也达到或超过油页岩边界品位4ω%.下古生界油页岩含油率普遍较高,最高含油率可达27.07%.云南油页岩矿资源有望成为重要的非常规油气资源. 相似文献
110.