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121.
Investigation of waste disposal areas using electrical methods: a case study from Chania,Crete, Greece 总被引:1,自引:0,他引:1
Pantelis Soupios Ilias Papadopoulos Maria Kouli Irene Georgaki Filippos Vallianatos Eleni Kokkinou 《Environmental Geology》2007,51(7):1249-1261
A geophysical investigation of a landfill area was conducted as inextricable phase of a preliminary geotechnical, geological
and hydrogeological study of the area under investigation. Electrical resistivity tomography (ERT), one of the most promising
prospecting techniques mainly concerning its effective contribution to resolve several environmental problems, was applied
for the geophysical modeling. ERT is a robust imaging method the theory and implementation of which are well documented in
geophysical research literature. The survey site is located in Akrotirion Peninsula, about 7 km east of Chania city in Crete
I. The geological setting comprises Trypalion limestones, marly limestones and a clayed weathered layer. Cavities are also
identified at various scales which are recent tectono-karstic voids. Due to the above-mentioned geological singularity and
in the light of the requirement for an environmentally safe construction of the landfill, an ERT survey was carried out. Specifically,
seven geoelectrical tomographies were conducted reaching the prospecting depth of 36 m. The resulted images conduced, to overcome
geotechnical problems since the spatial distribution of karstic voids was determined, to plan the future sites for waste disposal
as the geological conditions were studied in detail and to reliably estimate the thickness of the already deposited wastes.
The resulted images were confirmed using available borehole logs and ambient noise measurements. 相似文献
122.
Eberhard Gischler Alex L. Thomas André W. Droxler Jody M. Webster Yusuke Yokoyama Bernd R. Schöne 《Sedimentology》2013,60(6):1432-1466
During Integrated Ocean Drilling Program Expedition 325, 34 holes were drilled along five transects in front of the Great Barrier Reef of Australia, penetrating some 700 m of late Pleistocene reef deposits (post‐glacial; largely 20 to 10 kyr bp ) in water depths of 42 to 127 m. In seven holes, drilled in water depths of 42 to 92 m on three transects, older Pleistocene (older than last glacial maximum, >20 kyr bp ) reef deposits were recovered from lower core sections. In this study, facies, diagenetic features, mineralogy and stable isotope geochemistry of 100 samples from six of the latter holes were investigated and quantified. Lithologies are dominated by grain‐supported textures, and were to a large part deposited in high‐energy, reef or reef slope environments. Quantitative analyses allow 11 microfacies to be defined, including mixed skeletal packstone and grainstone, mudstone‐wackestone, coral packstone, coral grainstone, coralline algal grainstone, coral‐algal packstone, coralline algal packstone, Halimeda grainstone, microbialite and caliche. Microbialites, that are common in cavities of younger, post‐glacial deposits, are rare in pre‐last glacial maximum core sections, possibly due to a lack of open framework suitable for colonization by microbes. In pre‐last glacial maximum deposits of holes M0032A and M0033A (>20 kyr bp ), marine diagenetic features are dominant; samples consist largely of aragonite and high‐magnesium calcite. Holes M0042A and M0057A, which contain the oldest rocks (>169 kyr bp ), are characterized by meteoric diagenesis and samples mostly consist of low‐magnesium calcite. Holes M0042A, M0055A and M0056A (>30 kyr bp ), and a horizon in the upper part of hole M0057A, contain both marine and meteoric diagenetic features. However, only one change from marine to meteoric pore water is recorded in contrast with the changes in diagenetic environment that might be inferred from the sea‐level history. Values of stable isotopes of oxygen and carbon are consistent with these findings. Samples from holes M0032A and M0033A reflect largely positive values (δ18O: ?1 to +1‰ and δ13C: +1 to +4‰), whereas those from holes M0042A and M0057A are negative (δ18O: ?4 to +2‰ and δ13C: ?8 to +2‰). Holes M0055A and M0056A provide intermediate values, with slightly positive δ13C, and negative δ18O values. The type and intensity of meteroric diagenesis appears to have been controlled both by age and depth, i.e. the time available for diagenetic alteration, and reflects the relation between reef deposition and sea‐level change. 相似文献
123.
城市居住单元环境质量的高分辨率遥感评价方法研究 总被引:5,自引:0,他引:5
高分辨率遥感影像由于其较高的空间分辨率使得在居住单元的尺度上进行城市环境质量的遥感评价成为可能。所研究的评价方法在选取传统的环境评价指标如绿地景观结构参数、建筑容积率参数基础上,提出了平均可视面积、影像地物交替复杂度以及山体、水体、绿地、道路等外界地物影响力等指标,进一步研究了相关指标的分析方法。最后采用模糊评判的方法得到各参数指标的评判矩阵,进一步获得各居住单元综合指标评价的最终结果。使用厦门市QuickBird遥感影像进行了相关评价方法的实验,对8个典型居住单元的环境评价实验研究表明,利用高分辨率影像进行城市人居环境质量评价是一种成本较低、简便可行的方法。 相似文献
124.
Magnetic Influences of Cement Dust on Soil in Industrial Area and Its Environmental Implications 总被引:1,自引:0,他引:1
To monitor environmental implications of cement dust on soil in industrial area, magnetic parameters and mineral compositions were measured by the samples of the cement dust, cement factory dustfall, cement, coal ash, topsoil of green space in the factory and topsoil outside the factory. Results showed that the major magnetic minerals in the samples were magnetite, the magnetic mineral particle size of cement dust, dustfall, cement and coal ash was coarse Multi-Domian (MD) and Pseudo-Single-Domain (PSD). As topsoil of green space in the factory and topsoil outside the factory were polluted by cement dust, their magnetic properties had been obviously changed; the concentration of magnetic minerals elevated and particle size became coarser. The magnetic parameters (χfd,χARM/χ,χARM/SIRM) value can reflect the pollution level of the soil, the lower its value was, the more serious soil was polluted. X-ray diffraction results showed that the mineral compositions of the topsoil of green space in the factory and topsoil outside the factory were quartz and calcite, which were the same as cement dust. Magnetic parameters combination characteristics of topsoil can monitor the soil environmental changes in cement industry area. 相似文献
125.
A palygorskite unit was discovered in a road cut of undifferentiated Tertiary limestone between the villages of El Pariso
and San Roman (18°49.309N, 88°37.861W) in the southeastern Yucatán Peninsula, Mexico. This is the southern most locality of
a clay-rich sedimentary unit reported in the literature for the Tertiary carbonates of the Yucatán Peninsula. This occurrence
indicates a much wider range of palygorskite-rich clay deposition than previously recognized. The lithology is 99% clay and
1% sand to silt size diagenetic quartz grains. The clay consists of approximately 85% palygorskite, 15% montmorillonite and
trace amounts of titanium oxides. EDS analyses on palygorskite are largely consistent with sedimentary palygorskites from
other coastal marine settings, however palygorskite has a low total Fe content (average = 0.40 wt% expressed as Fe2O3) compared to many other sedimentary palygorskites. Montmorillonite chemical compositions are typical and compared to the
palygorskite have substantially higher Fe2O3 concentrations (average = 3.90 wt%). The low percentage of coarse grains in the lithology combined with a high proportion
of palygorskite and lack of detrimental trace minerals suggest the deposit is of industrial grade; however, it has limited
reserves (6,000 m3). The unit could be potentially used in a wide array of environmental applications which are needed in the region including
liners for landfills and constructed wetlands. The unit is in a geographic location which would serve the expanding economy
of the region. This resource has the potential to have great impact on the quality of the local environment and the economy
of a region under great environmental threat. 相似文献
126.
洞庭湖区的区域环境水文地质现状 总被引:13,自引:0,他引:13
据综合污染指数计算分析,洞庭湖区域浅层地下水分为重度,中度、轻度和非污染4个等级。区域环境水文地质恶化的主要原因是工农业生产,血吸虫防治和居民生活所造成的人为污染,应重点从保护自然环境,合理开采地下水、科学使用农药化肥,改革工业结构,健全环保法规等方面进行预防和治理。 相似文献
127.
长江三角洲环境地质调查评价GIS管理系统建设初探 总被引:5,自引:1,他引:5
长江三角洲是一个人口稠密、经济高度发达的地区 ,该区地质结构复杂、环境地质条件十分脆弱 ,长期以来因过量开采地下水 ,形成大面积区域性水位降落漏斗 ,诱发了相当严重的地面沉降、地裂缝等地质灾害 ,给当地经济可持续发展带来严重威胁。本文从开展长江三角洲环境地质调查评价的现实意义出发 ,探讨了长江三角洲环境地质调查评价GIS管理系统的系统目标、开发模式以及实现步骤 ,概括介绍了系统所应具有的功能 ,为长江三角洲项目信息系统建设提出了一条可行性思路。 相似文献
128.
《Geoforum》2014
The high-growth, resource- and pollution-intensive industrialization model that China has pursued has caused severe environmental pollution and deterioration, particularly in a number of clusters in the coastal regions of East and Southeast China, where the Reform and Opening-up policies first started. The lack of uptake of environmental norms/values, deficit of regulatory enforcement of environmental policies, and insufficient institutional capacity have been compounding factors. As environmental standards were raised by China’s central government, the enforcement of environmental regulation has been compromised more in inland China than in coastal regions, due to China’s “decentralized governance structure” and regional disparity in terms of both economic development and environmental pollution. This paper therefore argues that rising environmental regulations, as well as firm characteristics, regional hub effect and political environment, have all been particularly important in forcing China’s pollution-intensive enterprises to restructure their production, through innovation, upgrading, geographical relocation, outsourcing and plant closure, especially in China’s coastal regions. It contributes to recent studies by developing a heuristic analytical framework that aims to be sensitive to the impacts of environmental regulation, political environment and regional hub effect over firm restructuring, but which does so by stressing these impacts are simultaneously inflected by the nature and attributes of firms. The empirical analysis suggests a roughly inverted “U”-shaped relationship between firm relocation tendency and firm size (or firm capability), resulting from complex interactions between political environment, regional hub effect and environmental regulation. 相似文献
129.
Based on the formation and development analysis of the environmental geological disaster of land subsidence, earth fissures and other geological disasters in the North China, it showed these disasters caused a very serious problem in some areas of the North China, such as the deep groundwater exploitation cone, which is accumulated with great damage and loss and is hard to be controlled, therefore, great attention should be paid. It is considered that the formation of the deep groundwater cone is the root of various geological environmental problems, and the groundwater cone recovery is the key to solve other environmental problems 相似文献
130.
M. F. Grasso R. Clocchiatti F. Carrot C. Deschamps F. Vurro 《Environmental Geology》1999,37(3):207-217
The aim of this paper is to verify whether lichens have the capacity to accumulate atmospheric contaminators linked to volcanic
activity. About 100 lichens were collected in 1994 and 1995 from two active volcanic areas in Italy: Mount Etna and Vulcano
Island. Twenty-seven elements were analyzed for each individual lichen using Instrumental Neutronic Activation Analysis and
Inductively Coupled Plasma-Mass Spectrometry. Lichen composition reflects the contribution of the volcanic particulate material,
and the two areas investigated can be distinguished on the basis of the concentration of some lithophile elements. Moreover,
the distribution in lichens of the elements (As, Sb, Br, Pb) – derived from gas emissions (plume, fumaroles) – also shows
different geochemical trends on Mt. Etna and Vulcano.
Received: 20 April 1998 · Accepted: 4 July 1998 相似文献