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9th EAGE/EEGS Meeting
- Conference date: 31 Aug 2003 - 04 Sep 2003
- Location: Prague, Czech Republic
- ISBN: 978-94-6282-116-3
- Published: 01 September 2003
1 - 50 of 180 results
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2-D data modelling by electrical resistivity tomography for complex subsurface geology (is it possible to improve electronic interpretation of resistivity measurements with multielectrode devices in undeterminated cases?)
Authors E. Cardarelli and F. FischangerIn the last years, there has been a widespread increase in the use of 2-D electrical methods surveys especially due to the development of automatically multiplexed measuring systems which facilitate the acquisition of a large number of measurements. These methods are mainly used to map area with complex subsurface geology, to study aquifers, and to identify covered structures in archaeological study. For this reason the interpretation and consequently the inversion procedure of electric methods has to be accurate.
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Geoinformation system of Czech Geological Survey - Geofond
By D. CápováBy decree of the Minister of Environment of the Czech Republic the organization of the Czech Geological Survey consists of two organizations under the direction of the Ministry of Environment: the Czech Geological Survey (CGS), and the Czech Geological Survey - Geofond (Geofond).
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Applications and modelling of high sensitivity potassium gradiometers for near surface geophysics
Authors I. Hrvoic, G. M. Hollyer, R. Groom, R. Jia and A. SzetoNear surface geophysical methods and their role in Archaeology; Environmental and Engineering; and Unexploded Ordnance Detection applications is migrating from "anomaly detection" to characterization. With this trend, some instrument manufacturers are conducting research and development in to equipment capable of resolving targets more effectively. This paper focuses on the development and field testing of GEM'S new Optically Pumped Potassium system. The new technology provides high sensitivity; rapid sampling and high bandwidth; and "clean" geophysical signal (i.e. low heading error). Gradient tolerance is also enhanced.
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Analysis of noise coherence in airborne magnetic gradients for UXO detection
Authors T. J. Gamey, W. E. Doll, L. P. Beard and D. T. BellIn boom-mounted magnetometer systems, the primary noise falls into two main categories: maneuver noise and rotor noise. The forrner is relatively low Frequency, while the latter is relatively high frequency. Frequency filters of various types have been used with success, but fall short where the noise is within the bandwidth of the signal. Such is often the case when searching for unexploded ordnance (UXO) and other shallow targets at rapid flight speeds. Under these conditions, helicopter noise can be reduced by making use of the fact that much of it is coherent between sensors. In this paper, we examine the coherence of various types of helicopter noise and demonstrate that measured vertical gradients can offer raw signal-tonoise improvements of 4:1 or more over comparable total field measurements.
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Geophysical investigations for groundwater in the lower Klamath Lake basin, Oregon
Authors R. B. French, M. D. Jenks and G. G. ConnardSince the early 1900's the Klamath Basin, in the western United States, has relied heavily on surface water for irrigation. A large infrastructure of dams, canals and pump stations has been developed to service approximately 1500 farms. In the summer of 2001, with drought conditions and a concern for endangered species, the United States Bureau of Reclamation completely cutoff all irrigation water from Upper Klamath Lake, leaving approximately 1500 farms without water for crops. A flurry of groundwater exploration ensued.
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Applying airborne electromagnetic induction in ground-water salinization and resource studies, West Texas
Authors J. G. Paine and E. W. CollinsIn 2001, two high-resolution airbome geophysical surveys were flown in West Texas using Fugro's MEGATEM II system to acquire time-domain EM (TDEM) and magnetic field data. One survey, flown at 100-m line spacing on the Edwards Plateau, identified and assessed groundwater salinization in an oil-field area. The second survey, flown at 400-m line spacing over a West Texas basin, identified favorable areas for groundwater exploration.
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Lamb wave analysis for non-destructive testing of concrete plate structures
Authors N. Ryden, Ch. B. Park, P. Ulriksen and R. D. MillerLamb waves are guided dispersive waves propagating in free plate structures (Lamb, 1917). By matching theoretical multimodal Lamb wave dispersion curves with experimental ones, shear wave velocity (Vs), Poisson's ratio (v), and thickness (d) of the tested plak structure can be evaluated. In this expanded abstract a practical approach for NDT of pavements and concrete structures utilizing multiple modes of Lamb wave dispersion curves is presented. Both the measuring procedure and the analysis scheme is described. A complete description of how to calculate theoretical Lamb wave dispersion curves and more details on this study were given in the original manuscript (Ryden et al. 2003).
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Outlook on the possibility for slope stability evaluation according to petrophysical data
Authors A. Frasheri, F. Dhima and B. CangaResults of the geophysical data for in-situ evaluation of the physical-mechanical properties of the rocks in the unstable slopes in Albania are presented.
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Application of 2D laterally constrained inversion and 2D smooth inversion of CVES resistivity data in a slope stability investigation
Authors R. Wisén, A. V. Christiansen, E. Auken and T. DahlinIn this paper we present how a 2D least squares algorithm, Res2Dinv (Loke and Dahlin, 2002), and the 2D Lateral Constrained Inversion (2D-LCI) algorithm (Christiansen et al., 2003) can be applied in geotechnical site investigations. The 2D-LCI algorithm performs a parameterized 2D Laterally Constrained Inversion (Auken and Christiansen, 2003) on resistivity data.
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Ground penetrating radar investigation of limestone cliff fracturing in the French Alps
Authors M. Jeannin, S. Garambois, D. Jongmans and C. GrégoireAmong many natural hazards, rock falls are a very frequent phenomenon in mountainous areas, characterized by its suddenness and its difficulty to predict. The growing urbanisation in these areas implies-to better assess this hazard, and consequently to determine the location and volume of a rock mass which could fall. The stability assessment of a rock mass is generally based on surface observations (slope morphology, structural properties of the massif, deformation measurements). Even if these studies are necessary, the lack of information within the rock mass and, particularly, on discontinuities (geometry, properties) leads to major problems in hazard assessment.
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New achievements in developing a high speed geoelectrical monitoring system for landslide monitoring
More LessLandslides are one of the major threats to human settlements and infrastructure, causing over time enormous human suffering and property losses than any other geological hazard. Especially in alpine regions, population pressure has prompted settlement to more extreme areas, which are, due to their geological settings, vulnerable to landslides. Therefore much effort has to be centred on risk detection, risk reduction and development of timely waming systems to prevent future loss of life and property.
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Seismic tomography to explore cleft zones below houses in the area of a stress system induced by deep coal mining activities
Authors D. Orlowsky, U. Hunfeld and B. LehmannDue to deep coal mining activities dwing the years from 1980 to 2000 in depths between 700 and 1000 m a local stress systcm was induced in the northern part of the Ruhr Area in Germany. Atter strong rainfall in November 2002 this stress system leads to visible clefts at the earth's surface (Figure 1) with a lateral extension of the cleft zone of more than 250 m over arable soil along a country road and directly below a house. To explore the cleft zone below the house the seismic tomography was used to detemine it's extension and dip and additionally to investigate if the cleft zone may have significant influence on the stability of the underground below the house fundaments.
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Satellite radar interferometry and reflection seismic: An integrated geophysical study on the great Ancona landslides
Authors A. Mazotti and F. RoccaThe Great Ancona Landslide is located in the Italian Adriatic coast, immediately westward of the harbour city of Ancona and interests an area of about 3.5 km2, with a landslide front of about 2 km. (Figure IA). It is an ancient landslide, its occurrence being known since 1700. In recent times, the most severe event took place on December 13th 1982, when a densely built section of the city was involved in the eastern part of the landslide.
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Hydroacoustic monitoring in the Tressange pilot site (Moselle, France)
By S. BernardieThe purpose of this study is to implement a new technique for monitoring the abandoned mines subjected to flooding: it consists of a hydroacoustic monitoring (sensor placed in water filling the mining cavity) in a broad frequency bandwidth (30 Hz-1 80 kHz). GISOS, a French scientific interest group concerned with the impact and the safety of the underground works in the field of the post-mining, aims amongst other at understanding the phenomena occurring in the old mining cavities in order to forecast their evolution. A very significant research effort is put on the monitoring methods for assessing degradation of the mining works, as they directly threaten the infrastructures located on the ground surface. One of the parameters, which have a significant role in the stability of the underground works, is water.
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Using geophysical methods to image the internal structure of mine waste rock piles
Authors D. Campos, M. Chouteau, M. Aubertin and B. BussiéreMine waste rock piles, or rockwaste dumps, containing metallic sulphides are a favourable environment for the generation of acid mine drainage (AMD). There are many physical, geochemical and biological processes that lead to the production of AMD within waste rock piles. One of the most critical of these is water flow and water distribution in the waste rock. To fully understand this process, it is critical to know the intemal structure of waste rock piles. In this paper, the authors show the results of an investigation where resistivity and ground penetrating radar (GPR) geophysical methods have been used to study mine dumps.
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Using seismic refraction and 2-D electrical imaging methods to detect boulders in Penang, Malaysia
Authors R. Saad, M. N. M. Nawawi and Z. Z. T. HarithThe hot and wet condition are the main factor in speeding-up the physical and chemical weathering process, as well as creating fractures on the rock. Further erosion and weathering will cause the rock to break into boulders, and eventually form a thick blanket of soil. The occurrence of landslide in Malaysia is believed primarily due to the unusual thick soil profile and high rainfall. Buried boulders can also disrupt civil engineering projects especially piling and hill cutting.
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Czech environmental and engineering geophysics
More LessThe geophysical methods in geotechnics, hydrogeology and in environment have a relatively rich tradition in the Czech Republic. The first geoelectrical measurement for the soil investigation and for the dam place choice was made in the years 1940 and 1941 by the doyen of Czech geophysicists Rudolf Bghounek, later the first professor for applied geophysics at the Natural Faculty in Charles University.
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Comparative study between the shallow seismic refraction and laboratory methods for detecting the mechanical properties of some limestone rocks
Authors A. Heleika and G. M. E. KamhDetermination of the mechanical parameters of rocks and soil are very useful for building and other civil engineering purposes, but the mechanical properties of sedimentary rocks have wide range of values and are much influenced by lithological factors. These parameters are usually measured in the laboratory from some collected samples. These samples not reflect the mechanical behavior of the whole rocks. In this work a comparative study for measuring the mechanical properties of some Eocene Limestone rocks along four selected sites by using the shallow refraction seismic method and the laboratory method had been carried out for judging which one is suitable for this purpose.
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Experimental seismic measurements with the application of a vibrator
Authors J. Vilhelm, J. Skopec and J. BártaSince 2001, grant of the Ministry of Transport and Communications of the Czech Republic "Application of Geophysical Methods for Checking the Condition of Czech Railway Tracks" includes geophysical measurements that are performed by the grant holder - G IMPULS Praha s.r.0. in cooperation with Charles University, Faculty of Science, Prague.
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Application of geophysical methods for checking the condition of Czech Railway tracks
More LessOn the basis of the decision of the Ministry of Transport and Communications of the Czech Republic on the provision of financial resources, the following grant was commenced in 2001 and will be completed in 2003: "Application of Geophysical Methods for Checking the Condition of Czech Railway Tracks".
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Resistivity monitoring for leakage detection at Hällby embankment dam
Authors P. Sjödahl, T. Dahlin and S. JohanssonIntemal erosion is one of the major reasons for embankment dam failures. Resistivity monitoring may have the possibility of detecting internal erosion processes and anomalous seepage at an early stage before the safety of the dam is at stake. This is done by analysing and comparing the seasonal resistivity variation schemes in the reservoir and inside the dam body. The technique is essentially non-destructive, which is particularly important when working with embankment dams where drilling and other penetrating investigations are normally avoided.
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Multi-electrode measurements at Thai Binh dikes (Vietnam)
Authors T. Canh, N. Trong Vu and A. WellerAbout 7000 km river dikes and sea dikes have been built in the northem provinces of Vietnam. Annually, Vietnamese govemment and people have spent a lot of money for maintenance and protection of the dike system against flooding. Nevertheless, breaks of the dikes still happen, which have serious consequences. The instability of dikes results from defects, termite nests, seepage effects, or distorted dike foundation. The origin of these effects is usually hidden in the dike's body or foundation. It is not directly visible. Methods of dike monitoring are necessary to assess the stability and the state of the dike.
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Geophysical applications to geotechnical projects in Australia and China
By B. WhiteleyCivil engineers use geophysics for site characterisation to reduce geotechnical risks associated with construction by improving the accuracy of geotechnical models and to provide design parameters. Unlike exploration geophysics where successful outcomes, i.e. new discoveries are improbable, geotechnical engineers always expect successful outcomes with geophysical interpretations accurately representing the subsurface.
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Geothermal planning maps based on geophysical measurements
Authors R. Kirsch, D. Eberle, B. Röttger, B. Siemon and W. VossThe use of near surface geothermal energy is not based on the temperature increase with increasing depth, but on the fact that under normal conditions no seasonal temperature differences are present at depths exceeding 10 m. Below that depth temperatures are 10 - 12°C all over the year. So subsurface temperatures are cooler in summer and warmer in the winter than surface temperature. This can be used for cooling purposes in the summer, and, using a heat pump, for heating in the winter (Fig. 1).
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Application of the 2-D resistivity tomography, electromagnetic profiling method and soil thermometry for a remedy of the existing road endangered by the slope instability shallow caves and other inhomogeneities in the karst area
More LessThe geophysical survey was carried out in Moravian Karst - the well-known national park of the Czech Republic that extends to the northeast from Brno city. This not very large but wonderful landscape is characterized by very high stage of karstification on one side and by intensive human activity from early age till these days on the other side. (There are many caves, sinkholes, rocky gorges and abysses as well as prehistoric stations, several castles, villages and remains of old industrial activities.)
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Dispersion diagram analysis for underground cavitie : A finite difference approach
Authors C. Gelis, D. Leparoux, J. Virieux, A. Bitri and S. OpertoIdentifiing physical phenomena induced by underground cavities on seismic surface waves will improve void detection methods involving surface seismic waves. Recent works (Leparoux et al., 2000) based on numerical analysis in elastic media with 2nd order finite differences method (Virieux, 1986) and experimental validation show the capability of Rayleigh waves to detect underground cavities, as well as other works (Shtivelman (2000)). Nevertheless, these results show the necessity of accurate numerical modelling taking into account weathered structures and different shapes of cavity. A new finite difference spatial stencil has been proposed by Saenger et al. (2000) for reducing numerical dispersion. After describing this numerical method applied to surface waves analysis, we present seismograms and dispersion diagrams for different cavity typlogies and shot gathers.
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Experimentation at a test site for detecting voids and buried objects with seismic methods
Authors D. Leparoux, G. Grandjean, O. Abraham and P. CoteThe presence of man-made and natural buried objects - and particularly voids - in the subsurface is a recurring problem in civil engineering and landscape management. For the past few years, and in conjunction with other classical methods, we have been testing the potential of seismic methods for detecting underground voids based on the techniques of P-wave reflection (Grandjean et al., 2002) and surface-wave diffraction (Leparoux et al., 2000).
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2D Resistivity imaging at the Alba Iulia citadel, Romania
Authors R. Lachapelle and C. Suteu2D Electrical resistivity imaging has been successfully used as a subsurface investigation tool in engineering and environmental investigations. We present the results of a 2-D resistivity imaging survey over a buried tunnel.
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Microgravity detection of the chambers caused by a battery breast coal mining
By V. BlechaThe area of study is located in the Northem Bohemia in the immediate vicinity of the Most town. The region is a traditional territory of brown coal mining. Horizontal and subhorizontal coal seams in the Tertiary sedimentary basin are surrounded by clays and claystones.
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High-resolution seismic reflection data reveal major fault zone in Lake Geneva, Switzerland
Authors F. Marillier, D. Dupuy, C. Proietti and M. ScheidhauerAlong the northern rim of the Swiss Alps, a major thrust fault zone separetes Plateau Molasse to the northwest fiom Subalpine Molasse to the southeast. This feature runs across the city of Lausanne and extends into Lake Geneva. Although fit is not observed on the southern shore of Lake Geneva probably because fit lies under a thick Quaternary cover, configuration of the AIpine units in this area suggests that the hult zone crosses the lake. To find out the location of the fault zone across the lake and to investigate its configuration, we acquired several high-resolution multi-channel seismic reflection profiles. The high quality of the seismic images obtained indicate that the fault zone includes a series of individual fault that can be accurately located.
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Seismic characteristics of shallow fault zones
Authors V. Shtivelman and S. MarcoDetecting and mapping fault zones in the shallow subsurface is an important problem in various applications, such as engineering site characterization, seismic risk assessment, archeology and others. The commonly used method for this purpose is the high resolution reflection seismics.
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Detecting fault of M = 7.6 Chi-Chi, Taiwan earthquake of 21 September 1999 using geophysical methods
By R. SunThe devastating M = 7.6 Chi-Chi, Taiwan Earthquake of 21 September 1999 caused about 2500 deaths and roughly US$12 billion in property loss. It is triggered by the rupture of the N-15°-E-striking, 120-km-long Chelongpu Fault, which is a direct result of the Philippine Sea Plate-Eurasia Plate collision, in central Taiwan.
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Mapping karst features using a 2-D resistivity survey
Authors Z. Z. T. Harith and A. DevendranThe presence of pinnacles, and underground cave / cavern are common phenomena in limestone area. The occurrence of ground subsidence and sinkholes are always associated with this karsts area. The area of known existence of buried karsts topography should be considered as an unsafe or unstable area. In order to have a suitable design, details investigation of the subsurface is needed. Conventionally it is done using a closed spacing soil investigation (drilling) method, of which is very costly. An altemative investigation method proposed here is the Resistivity Imaging Technique. This is one of many types of geophysical investigation technique, which can be used to investigate the subsurface. On this site, it was proposed to use a 2-D Resistivity Imaging technique.
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Optimizing the 2D laterally constrained inversion (2D-LCI) using a Quasi-Newton method and 1D derivatives
Authors A. V. Christiansen and E. Auken2D laterally constrained inversion (2D-LCI) is a new approach to interpretation of continuous resistivity data. The 2D-LCI enables a layered 2D inversion with sharp layer boundaries as compared to traditional smooth inversion types. However, the full 2D solution is quite time consuming when calculating the derivatives in the Jacobian matrix. To reduce the computation times we suggest using 1D derivatives, Broyden's update formula (Quasi- Newton) or combinations of Broyden's update formula and 1D derivatives together with the full 2D solution. The reduction in computation time is between 7 and 30 times dependent on the combination of approximations.
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3D resistivity finite element modelling using mesh-independent electrode location
Authors L. Marescot, S. P. Lopes, S. Rigobert, R. Lagabrielle and D. ChapellierThe finite element method (FEM) has been used by several authors in the context of direct current (DC) forward modelling to calculate the response of surveys on complex earth structures (e.g. Coggon, 1971; Pridmore et al., 1981; Sasaki, 1994). In practice, geophysicists often wish to use the same electrode sequence for the simulation of different surveys.
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Optimizing the information content of DC resistivity data
Authors H. Maurer, P. Stummer and A. G. GreenIn an attempt to exploit better the capabilities of multi-electrode acquisition systems, we have developed an experimental design procedure to identifi suites of electrode configurations that provide maximum subsurface information. The experimental design algorithm is based on a goodness function that ranks the sensitivity of every possible electrode configuration to changes in the subsurface parameters. To examine the potential and limitations of the new algorithm, we performed a synthetic experiment and compared the resolution power of the optimized data sets with those of Wenner and dipole-dipole configurations. The results indicate that the optimized configurations lead to substantially better inversion results than the standard data arrays.
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Phase difference analysis for surface wave methods
Authors C. Strobbia and S. FotiSurface wave propagation can be analysed using a variety of signal processing techniques, most of which are based on spectral analysis. Transient data are decomposed into their monochromatic components: at each frequency the phase information can be used to compute the phase velocity, while the amplitude can be used to estimate the material attenuation. SW methods use the dispersive properties of Raleigh waves to infer the shear wave velocity profile at a site. Similarly the material attenuation can be used to estimate the dissipative properties of the deposit.
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Study on surface wave resolution
Authors L. V. Socco and C. L. StrobbiaIn order to evaluate the effectiveness of a survey method and to supply information for survey planning it is very useful to estimate the spatial resolution related to investigation depth that can be achieved by the survey in different conditions.
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Laterally consistent, correct elimination of the source signature in shallow, high-resolution seismic reflection surveys: possibility and benefits
By R. GhoseFor safe and efficient design and construction of structures, as well as for environmental and hydrogeological reasons, lateral variations in the shallow subsurface are important targets of investigation. A lack of knowledge of the lateral continuity or discontinuity of shallow soil layers or of lateral change in the physical nature of a layer has caused serious accidents in the past. Significant increase in the construction cost and unacceptable delays are also common. There are occasions when localized discontinuities in the clay cap layer have caused contamination of pure water at greater depths.
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Non linear inversion of noise array measurements for determining S-wave velocity vertical profiles
Authors M. Wathelet, M. Ohrnberger, D. Jongmans, T. Camelbeeck and F. ScherbaumThe knowledge of the shear wave velocity (VS) profile at a given site is of major importance in earthquake engineering. The geophysical techniques generally used in soil dynamics to obtain shear wave velocity as a function of depth are the borehole tests (Jongmans, 1992), which are expensive and limited to shallow depths.
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Wavefield composition and decomposition for the electro-kinetic reflection
Authors A. Ranada, E. Slob and C. P. A. WapenaarThe electro-kinetic effect represents a class of processes in which there is a conversion from electromagnetic to kinetic energy and vice versa. In the case of this transfer taking place in a saturated porous medium we name the effect electro-seismic for the transfer from electromagnetic to kinetic energy, and seismo-electric for the transfer from kinetic to electromagnetic energy.
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Using a lattice solid model for vertical seismic profiles
Authors N. Fillipidou, S. Abe and G. G. DrijkoningenThe transmission of seismic energy through a sequence of layers consisting of unconsolidated material is by itself a challenging problem. The seismic pulse is known to broaden slightly with propagating distance, often described with a damping factor Q. In shallow sediments damping is very high compared to rocks, and should therefore show more pronounced effects of energy loss. One part of the losses can be described by viscoelastic losses, although viscosity is not the reality but is a way of giving a phenomenological description of damping. From a physical point of view, particles that can move in relation to each other seems to be more evident in unconsolidated or partly consolidated mediums like soils and other soft sedimentary formations.
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Airborne geophysics for shallow object detection: Technology update 2003 - electromagnetics
Authors T. J. Gamey, W. E. Doll, L. P. Beard and D. T. BellORNL has been developing helicopter-mounted geophysical systems for detection of shallow buried objects since 1997. In collaboration with the U.S. Army Engineering Support Center - Huntsville and private sector partners we have focused our efforts on UXO detection and characterization, but the system is equally well adapted to any large area shallow mapping project such as utility locating, brownfield studies, hazardous waste sites and archeological sites.
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Airborne geophysical surveys assessing the general scale quaternary mapping project in Finland
Authors E. Hyvönen, J. Lerssi and T. VäänänenGeological Survey of Finland has mapped surficial Quatemary deposits mainly at a scale 1:20000. These large scale maps cover only part of Finland. To fulfil the needs of the customers and the authorities a new mapping program begin in 2003 to produce maps and database at scale 1:250 000, covering whole Finland by the year 2007. The new database will contain geospatial distribution of sediment polygons and related attribute information. It will be produced by interpreting, modifying and generalising existing spatial data using GIS- and image processing techniques with minimum amount of field work (Nevalainen et al., 2002).
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A detailed inversion scheme for helicopter-borne electromagnetic frequency-domain data
Authors R. J. Tølbøll and N. B. ChristensenGround-based electromagnetic methods have for many years successfully been employed for hydrogeological investigations in Denmark. A wish for higher efficiency has led to a growing interest in the possibility of using airborne electromagnetic methods in the mapping campaign, and lately the helicopterborne electromagnetic frequency-domain (HEM) method has been in focus.
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SkyTEM - new development in high-resolution airborne TEM
Authors K. I. Sørensen and E. AukenIn Denmark, 99% of the water supply is based on groundwater abstraction. Increasing problems with the groundwater quality, due to urban growth and agricultural contamination, have caused the Danish Minister of Environment to approve a plan for improving ground water protection.
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Ground penetrating radar modelling of rough underground interfaces
Authors A. Giannopoulos and N. DiamandiIn many electromagnetic scattering problems, the Earth's surface as well as subsurface interfaces are often modeled as planar dielectric boundaries (Cui and Chew, 1999). However, this assumption is not always valid and roughness in the Earth's subsurface can potentially be a major source of variability in the obsewed GPR signals. In some applications where shallow targets have constitutive properties very close to those of the background medium clutter due to the rough interface may introduce severe constraints on target localization and identification. As a result the detection of a buried object under a rough subsurface interface, using ground penetrating radar (GPR) could become problematic.
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Mineral detection by a new approach to the compact inversion of gravity data
More LessA new approach for computing the regularization parameter in compact gravity inversion (Last and Kubik,1983) is presented. Neyman (1979) procedure for discrete data is used for the regularization parameter. A field example is demonstrated . Key words: Compact inversion, regularization parameter, mineral detection.
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Polarization and acquisition in GPR surveys: tests on physical models
Authors P. Capizzi, P. L. Cosentino and L. RomanoIn most cases GPR surveys are carried out using co-pole data, because cross-pole data are generally not acquired. However, in the planning of GPR survey it is important to consider the antenna polarization, as the sensitivity of cross-pole and co-pole configurations is connected with the type of target as well as with the subsurface conditions.
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