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1.
Pantelis Soupios Nikos Papadopoulos Ilias Papadopoulos Maria Kouli Filippos Vallianatos Apostolos Sarris Thrassyvoulos Manios 《Environmental Geology》2007,53(3):661-675
An integrated suite of environmental methods was used to characterize the hydrogeological, geological and tectonic regime
of the largest waste disposal landfill of Crete Island, the Fodele municipal solid waste site (MSW), to determine the geometry
of the landfill (depth and spatial extent of electrically conductive anomalies), to define the anisotropy caused by bedrock
fabric fractures and to locate potential zones of electrically conductive contamination. A combination of geophysical methods
and chemical analysis was implemented for the characterization and management of the landfill. Five different types of geophysical
surveys were performed: (1) 2D electrical resistance tomography (ERT), (2) electromagnetic measurements using very low frequencies
(VLF), (3) electromagnetic conductivity (EM31), (4) seismic refraction measurements (SR), and (5) ambient noise measurements
(HVSR). The above geophysical methods were used with the aim of studying the subsurface properties of the landfill and to
define the exact geometrical characteristics of the site under investigation. 相似文献
2.
Gökhan Göktürkler Çağlayan Balkaya Zülfikar Erhan Ayça Yurdakul 《Environmental Geology》2008,54(6):1283-1290
Near-surface geophysical methods are commonly used to solve a wide class of geological, engineering and environmental problems. In this study, a geoelectrical survey was performed to investigate an alluvial aquifer. The study area is located in the southwest of the Çubukluda? graben, situated in the south of ?zmir, Turkey. The geophysical studies included the electrical resistivity imaging and self-potential (SP) methods. The resistivity data were acquired along eight profiles in the northern part of the study area by a Wenner-Schlumberger electrode configuration and the data processing was achieved by a tomographic inversion technique. The SP data were collected by gradient technique along 16 profiles. Total field values were calculated for each profile by addition of the successive gradient values, then a total field SP map was obtained. The water-saturated zone in the northern part of the study area was clearly revealed by the electrical resistivity imaging and the SP survey yielded useful information on the subsurface fluid movement. 相似文献
3.
The selection of the disposal site is probably the most important step in the development of solid waste management. In site selection, geology plays a determining role. This study evaluates the characteristics of the environment on the basis of the geological, hydrogeological and geo-engineering properties of the solid waste site of the Sivas city, Turkey. The area is underlain by the Oligocene-Miocene rocks which have limited aquifer properties. Thin Quaternary alluvium and soil cover overlie the Oligo-Miocene rocks, which are represented as well graded sand and inorganic silt of low plasticity. The Quaternary alluvium and soil cover are classified as inorganic clays having a low plasticity and the permeability varies from 1.2×10−6 to 3.11×10−6 m/s. These values are much higher than 1×10−8 m/s, which is accepted for waste disposal standards. Seepage waters have a potential to pollute the ground water and the Kızılırmak River, which is 500 m to the southwest of the waste disposal area and because the disposal site is close to the river, the potential for flash flooding poses a high pollution risk. The waste disposal area must be covered by clay layers or an impervious artificial membrane. In addition, seepage must be controlled and removed from the site. 相似文献
4.
Earthquake vulnerability and seismic risk assessment of urban areas in high seismic regions: application to Chania City,Crete Island,Greece 总被引:1,自引:1,他引:1
The earthquake vulnerability and the seismic risk assessment for the urban center of Chania in the island of Crete is approached
through the development of a GIS-based application that takes into consideration the structural and geological domain of the
region. Considering a localized model, the various structural and geomorphologic attributes of the region were assigned specific
weights of significance that allowed the creation of a modular application that was tested for the city of Chania, and it
was verified based on the recent seismic activity of the area. The proposed risk map and model can become a significant tool
for confronting crises resulting from future earthquake incidences. 相似文献
5.
Soil erosion prediction using the Revised Universal Soil Loss Equation (RUSLE) in a GIS framework,Chania, Northwestern Crete,Greece 总被引:7,自引:0,他引:7
Soil erosion is a growing problem in southern Greece and particularly in the island of Crete, the biggest Greek island with
great agricultural activity. Soil erosion not only decreases agricultural productivity, but also reduces the water availability.
In the current study, an effort to predict potential annual soil loss has been conducted. For the prediction, the Revised
Universal Soil Loss Equation (RUSLE) has been adopted in a Geographical Information System framework. The RUSLE factors were
calculated (in the form of raster layers) for the nine major watersheds which cover the northern part of the Chania Prefecture.
The R-factor was calculated from monthly and annual precipitation data. The K-factor was estimated using soil maps available from the Soil Geographical Data Base of Europe at a scale of 1:1,000,000.
The LS-factor was calculated from a 30-m digital elevation model. The C-factor was calculated using Remote Sensing techniques. The P-factor in absence of data was set to 1. The results show that an extended part of the area is undergoing severe erosion.
The mean annual soil loss is predicted up to ∼200 (t/ha year−1) for some watersheds showing extended erosion and demanding the attention of local administrators. 相似文献
6.
Mahmut G. Drahor Gökhan Göktürkler Meriç A. Berge T. Özgür Kurtulmuş 《Environmental Geology》2006,50(2):147-155
Electrical resistivity imaging is a widely used tool in near surface geophysical surveys for investigation of various geological, environmental and engineering problems including landslide. In this study, an electrical resistivity tomography (ERT) survey was conducted in a landslide area, located in the Söke district of Aydın, Turkey. In 2003, the Neogene-aged units on the slope next to a newly built school building became unstable due to an excavation work and moved after a heavy rainfall. The resulting landslide partly covered the school. The authors carried out a 2-D resistivity survey along three profiles over the landslide mass using a Wenner configuration. It yielded useful information about the geometry and characteristics of the landslide. In addition, a 2-D synthetic resistivity modelling study was carried out to understand the response of the resistivity method to a landslide problem before the field surveys. Eight boreholes were also drilled in the landslide area. Both the drilling and resistivity results indicated the presence of a fault in the site. Also, the resistivity data from the line measured along the axis of the landslide revealed the surface of rupture. 相似文献
7.
The present work demonstrates the environmental problems associated with the development and operation of a lined and unlined
landfill site, both used for municipal solid waste landfilling, that are situated next to the city of Patra, Greece. Findings
from a detailed site investigation as well calculations on hydrologic evaluation of landfill’s performance and measurements
on leachate composition proved that the lined landfill site is more secure and environmental friendly compared with the unlined
landfill site. Even though, until today, there is no evidence from near boreholes for severe contamination problems generated
by any of the two landfills, in the forthcoming future several environmental problems are expected to occur from the unlined
site. In addition the prevailing hydrogeotechnical conditions indicated that the unlined site is a potential source of contamination;
hence extra remedial measures should be received by the local authorities to prevent severe contamination in soil and groundwater. 相似文献
8.
Christoph Spötl Yuri Dublyansky Michael Meyer Augusto Mangini 《International Journal of Earth Sciences》2009,98(3):665-676
The area south of the prominent east–west trending Salzach Valley at the northern rim of the Central Alps of Austria has long
been known to host anomalously warm springs emerging from a highly deformed calcite marble (Klammkalk). This unit also hosts
cavities whose shapes suggest a hydrothermal karst origin and which are lined by calcite spar. We report here petrographic
and isotopic evidence suggesting that dissolution by ascending low-temperature thermal waters also played an important role
in the origin of a large cave in this region, Entrische Kirche. A paleo cave wall, preserved behind a thick flowstone in the
interior of this cave, revealed a brownish bleaching zone which contrasts to the medium grey colour of the unaltered marble
beneath. Across this zone the C and O isotope values gradually decrease by 3 and 11‰, respectively. These compositions are
very different from those of the speleothem above but are similar to phreatic calcite spar from hydrothermal karst cavities
in other outcrops in the area, where the absence of two-phase fluid inclusions suggests a low-temperature (less than ca. 50°C)
hydrothermal origin. U/Th dating of the flowstone capping the alteration zone yielded a minimum age of the thermal water invasion
in Entrische Kirche of ca. 240 kyr. There is no evidence in Entrische Kirche that these palaeowaters reached the point of
calcite precipitation, but it is physically conceivable that higher and as yet unexplored parts of this deep (ca. 900 m) cave
contain cavities lined by phreatic cave spar. 相似文献
9.
Mining firms stimulate local and national economies but this comes at a certain cost. In the light of increasing public concern, external costs of environmental degradation and social disruption are no longer of pure academic interest. The assessment of mining projects on the grounds of sustainable development is critical in order to decide whether the exploitation of mineral resources is socially desirable. In practice, few steps have been taken towards this end. In this paper, a case study is illustrated that provides the means for evaluating the social worthiness of mining projects. The analysis, which is the first of its kind in Greece, deals with a major problem of the mining industry: the gold debate on the grounds of green economics. The assessment is based on the social cost–benefit approach. Well-established techniques (e.g. benefit transfer) and innovative approaches have been adopted to overcome various practical problems 相似文献
10.
W. D’Alessandro L. Brusca K. Kyriakopoulos G. Michas G. Papadakis 《Environmental Geology》2009,57(8):1723-1728
Volcanic and geothermal areas are one of the major natural sources of H2S to the atmosphere. Its environmental impact is often the main cause of the opposition to the development of geothermal energy
exploitation programs. In this paper, we analyze the air concentrations and dispersion pattern of naturally emitted H2S at the geothermal area of Sousaki (Corinthia, Greece). Measurements, made with a network of passive samplers, evidence a
rapid decrease of concentration values away from the emission points. The fact that the decrease is more pronounced in the
summer with respect to the winter indicates that it is not only due to a dilution effect, but also to redox reactions favored
by higher temperatures and intense sunlight typical of the summer period. 相似文献
11.
Geophysical methods, when integrated with soil chemical and hydrogeological methods, can be used to investigate groundwater
contamination. Direct current (DC) resistivity geo-electrical sounding and very-low-frequency electromagnetic (VLF-EM) data
were collected at an open waste site used by the municipality of the city of Isparta, Turkey. The groundwater at shallow depths
in alluvium, which is composed of gravel, sand and clay, were expected to be hazardously contaminated under and around the
open waste-disposal site, in which both household and industrial wastes are known to be disposed of improperly. In this study,
we mapped the spread of groundwater contamination using a VLF-EM method, which allows fast and inexpensive data collection.
The method complements the results of geo-electrical sounding. There is a good correlation between the results of the VLF-EM
and the DC-resistivity methods employed for the investigation of subsurface structure of the site, where soil chemical and
previous hydrogeological surveys have indicated high levels of chemical concentrations.
Received: 17 January 2000 · Accepted: 12 August 2000 相似文献
12.
《Applied Geochemistry》1988,3(3):273-280
A bronze cannon was used as an analogue of corrosion processes for Cu. The cannon has been embedded in clay sediments in the Baltic Sea since 1676. Corrosion products are cuprite and malachite, mainly derived from transformation of tenorite inclusions of the bronze alloy. The bronze matrix exhibits little corrosion and a conservative estimate for the maximum corrosion of Cu is <10 mm in 100,000 a. Mechanisms for the chemical corrosion processes are suggested. 相似文献
13.
Ahmet Evren Erginal Beyhan Öztürk Yunus Levent Ekinci Alper Demirci 《Environmental Geology》2009,58(6):1167-1175
The nature and subsurface structure of the slip surface of a landslide was studied on the basis of geochemical analyses and
2-D electrical resistivity tomography (ERT) survey. Head scarp and lateral slip surfaces of the landslide marked by clear
slickensided shear planes were composed of the average amounts of clayey silt (32.5%) and sand (67.5%). Energy dispersive
X-ray spectroscopy (EDX) data revealed the enrichment of Si (23.24%), Fe (12.2%), Al (9.51%) and C (8.34%) in the elemental
composition of the disturbed slip surface. From X-ray diffractometry (XRD) data, six main clay types were determined, such
as Volkonskoite, Halloysite, Ferrosilite, Saponite, Illite and Nontronite. The ERT survey displayed that the landslide developed
as a reactivation on the upper part of an old landslide body. 相似文献
14.
Control of slope deformations in high seismic area: Results from the Gulf of Corinth observatory site (Greece) 总被引:1,自引:0,他引:1
The northern coast of the Peloponnesus (Greece) is characterized by high seismic activity related to the Gulf of Corinth opening with an extension rate of 16 mm y− 1. Studies presented in this paper focus on the characterization of links between tectonic and slope deformations on the Panagopoula slope, located on the southern coast. The approach is centred on qualitative and quantitative data acquisition based on geological and geomorphological investigations, geophysical imagery by electrical resistivity tomography and slope displacement monitoring.Firstly, we highlight two different types of slope deformation on Panagopoula: a superficial landslide affecting weathered limestone, and a large-scale deformation without global failure expressed in the field. Tectonic features play a major role in these two dynamic processes, taking into account the strong geometrical link between the inherited fractures and gravitational scarps mapped in the field.Secondly, the displacements survey network, distributed on both sides of a significant fault crossing the slope, allows the quantification of slope displacements underlying two components: (i) a gravitational sliding (N010) along the slope, and (ii) a supposed tectonic component (N240). 相似文献
15.
Mashalah Khamehchiyan Mohammad Reza Nikoudel Mehdi Boroumandi 《Environmental Earth Sciences》2011,64(7):1763-1776
The study of landfill sites is one of the most important studies in landfill engineering, and the landfill site selection
involves combination of engineering, science, and politics. This paper describes a comprehensive hazardous waste landfill
site selection methodology with the combined utilization of geographic information system and multiple criteria analysis methods,
as applied to the Zanjan province in Iran. The six main data categories that were used are geological/engineering geological,
geomorphological, hydrological/hydrogeological, climatological, pedological, and social/economical criteria, which included
31 input layers in total. A suitability map for hazardous waste landfilling was prepared for study area with five classes
from most suitable to completely unsuitable. Finally, out of the three sites, one site was selected which was chosen by the
local authorities. Our work offers a comprehensive methodology and provides essential support for decision-makers in the assessment
of hazardous waste management problems in Zanjan province in I.R. Iran and other developing cities in other countries. 相似文献
16.
Geochemical characterisation and geophysical mapping of Landfill leachates: the Marozzo canal case study (NE Italy) 总被引:1,自引:0,他引:1
An integrated approach including geochemical analyses and geophysical investigations, aimed at characterizing the chemical composition of leachate and at highlighting the extent and magnitude of the plume in terms of spatial distribution is presented. The reason for the specific induced polarisation behaviour over landfills was not well understood. In this work we propose an explanation for this behaviour, which is being used to detect the presence of possible leaks and to track and delimit the pollution plume for several years.As a case study the example of an abandoned municipal solid waste landfill, located in Comacchio County, NE Italy, is presented, where the operative conditions for any resistivity monitoring method were to be excluded because of the high salinity of the phreatic aquifer. 相似文献
17.
A. Perrone G. Zeni S. Piscitelli A. Pepe A. Loperte V. Lapenna R. Lanari 《Engineering Geology》2006,88(3-4):260-273
We have jointly applied microwave remote sensing imaging and ground-based geophysical methodologies for investigating ground deformation. In particular, the Differential Interferometric Synthetic Aperture Radar (DInSAR) technique referred to as Small BAseline Subset (SBAS) algorithm and the Electrical Resistivity Tomography (ERT) method have been applied. The former is a tool for investigating large areas, allowing us to detect deformation phenomena and to analyse their spatial patterns and temporal evolution; the latter permits us to reconstruct, with high spatial resolution, the geometry of near-surface geological structures and to estimate the electrical resistivity of outcropping terrains. The starting point of our analysis has been a DInSAR survey carried out on an area of about 400 km2 centred around the town of Potenza (Basilicata region, Italy), for which SAR data acquired by the ERS-1/2 sensors in the time interval 1992–2000 were available. The DInSAR analysis allowed us to detect an unknown ground deformation effect which involves the urban area of Satriano di Lucania, located close to Potenza. An on-site ERT survey was then carried out in order to characterize in detail the physical properties of the terrains involved in the main deformation pattern detected via the DInSAR processing. The integration of the DInSAR and ERT measurements permitted us to investigate areas where the deformation have space-variant characteristics and allowed us to formulate a hypothesis on the origin of the detected displacement processes that, although not fully conclusive, is consistent with the overall DInSAR and ERT analysis. 相似文献
18.
As landslides are very common in Greece, causing serious problems to the social and economic welfare of many communities,
the implementation of a proper hazard analysis system will help the creation of a reliable susceptibility map. Τhis will help
local communities to define a safe land use and urban development. The purpose of this study is to compare the implementation
of two semi-quantitative landslide assessment approaches, using landslide susceptibility maps compiled in a GIS environment.
The compared methods are rock engineering system (RES) and the analytic hierarchy process (AHP). For the landslide susceptibility
analysis, the Northeastern part of the Achaia County was examined. This area suffers from many landslides, because of its
neighborhood with the tectonically active Corinthian Gulf and its geological setting (Neogene sediments, flysch and other
bedrock formations, with local overthrusts). Ten parameters were used in both methodologies, and each one was separated into
five categories ranging from 0 to 4, representing their specific conditions derived from the investigation of the landslides
in the western part of the study area (ranking area). A layer map was generated for each parameter, using GIS, while the weighting
coefficients of each methodology were used for the compilation of RES and AHP final maps of the eastern part of the study
area (validating area). By examining these two maps, it is revealed that even though both correctly show the landslide status
of the second site, the RES map reveals a better behavior in the spatial distribution of the various landslide susceptibility
zones. 相似文献
19.
Environmental impact of mining waste disposal on a tropical lowland river system: a case study on the Ok Tedi Mine, Papua New Guinea 总被引:3,自引:0,他引:3
The 1000 km long Ok Tedi/Fly River system receives about 66 Mt/year of mining waste from the Ok Tedi copper-gold porphyry
mine. Mine input has increased the suspended sediment load of the Middle Fly River about 5–10 times over the natural background.
A significant yet unknown amount of copper-rich material deposits unevenly in the extensive tropical lowland floodplain. Recent
alluvial sediments of the Fly River floodplain have copper contents of 620 mg/kg (±1σ: 430–900), whereas the regional background
is 40 mg/kg (±σ: 25–60). This pattern is mirrored and enhanced by the gold dispersal pattern with a 7 ppb Au background versus
a 140–275 ppb population in mine-derived material. Very high deposition rates (around 4 cm/y) of mine-derived sediment were
determined in locations close to the creeks and channels which link the Fly River with the outer floodplain. A thin layer
of 1–5 cm of copper-rich material (400–900 mg/kg Cu) was usually found on the bottom of drowned (tributary) valley lakes.
Average dissolved copper content in waters of the inner floodplain is around 9 μg/l (±1σ: 5–14) as compared to unpolluted
water from the outer floodplain with < 2 μg/l Cu. The present Fly River water, about 600 km downstream of the mine site, has
concentrations of 17 ± 3 μg/l dissolved Cu.
Received: 30 June 1996 / Accepted: 9 January 1997 相似文献
20.
Salinity mapping of coastal groundwater aquifers using hydrogeochemical and geophysical methods: a case study from north Kelantan,Malaysia 总被引:2,自引:0,他引:2
Integrated hydrogeochemical and geophysical methods were used to study the salinity of groundwater aquifers along the coastal
area of north Kelantan. For the hydrogeochemical investigation, analysis of major ion contents of the groundwater was conducted,
and other chemical parameters such as pH and total dissolved solids were also determined. For the geophysical study, both
geoelectrical resistivity soundings and reflection seismic surveys were conducted to determine the characteristics of the
subsurface and groundwater contained within the aquifers. The pH values range from 6.2 to 6.8, indicating that the groundwater
in the study area is slightly acidic. Low content of chloride suggests that the groundwater in the first aquifer is fresh,
with an average concentration of about 15.8 mg/l and high geoelectrical resistivity (>45 ohm m). On the other hand, the groundwater
in the second aquifer is brackish, with chloride concentration ranging from 500 mg/l to 3,600 mg/l and very low geoelectrical
resistivity (<45 ohm m) as well as high concentration of total dissolved solids (>1,000 mg/l). The groundwater in the third
aquifer is fresh, with chloride concentrations generally ranging from 2 mg/l to 210 mg/l and geoelectrical resistivity of
greater than 45 ohm m. Fresh and saltwater interface in the first aquifer is generally located directly in the area of the
coast, but, for the second aquifer, both hydrogeochemical and geoelectrical resistivity results indicate that the fresh water
and saltwater interface is located as far as 6 km from the beach. The considerable chloride ion content initially suggests
that the salinity of the groundwater in the second aquifer is probably caused by the intrusion of seawater. However, continuous
monitoring of the chloride content of the second aquifer indicated no significant changes with time, from which it can be
inferred that the salinity of the groundwater is not affected by seasonal seawater intrusion. Schoeller diagrams illustrate
that sulphate concentrations of the groundwater of the second aquifer are relatively low compared to those of the recent seawater.
Therefore, this result suggests that the brackish water in the second aquifer is probably from ancient seawater that was trapped
within the sediments for a long period of time, rather than due to direct seawater intrusion. 相似文献