Site investigation methods for seismic reflection surveying, seismic data processing, and. Application of geophysical and geotechnical methods to site characterization for construction purposes at ikoyi, lagos, nigeria k. Geophysics has been shown to be effective in identifying areas contaminated by waste disposal, contributing to the greater efficiency of soundings programs and the installation of monitoring wells. The science of geophysics applies the principles of physics to the study of the earth. Application of modern seismic methods for geotechnical. Airborne geophysical methods will continue to be dominant for fast, costeffective, and largescale studies e.
The electrical resistivity method is one that has been widely used because of the theoretical, operational and interpretational ease. A geophysical investigation campaign consists in acquiring physical data on the levee structure from the variations of a measured physical field. Standard references for geophysical investigations standard. Standard references for geophysical investigations.
Seismic survey is the geophysical method, which is most closely related to rock and soil mass properties, since seismic wave velocity. Exploration geophysics is an applied branch of geophysics and economic geology, which uses physical methods, such as seismic, gravitational, magnetic, electrical and electromagnetic at the surface of the earth to measure the physical properties of the subsurface, along with the anomalies in those properties. Surface drainage is the subdued replica of topography. Jun 18, 2016 presentation on geophysical methods 1. Hunt the investigation phase is the most important segment of any geotechnical study. Pdf on jan 1, 2007, steven f thornton and others published the use of geophysical investigation techniques in the assessment of. In gravity prospecting we are mostly interested in lateral variations in earth structure, because these involve lateral variations in. This document can also be obtained through epas clean up. The methods and instruments we use are chosen to meet the specific needs of our clients and accommodate the existing field conditions. The surface methods of groundwater exploration include the following.
To reduce this number to 11, epa applied the following criteria to each geophysical investigation. Detection and analysis of the geophysical signals forms the core of geophysical signal processing. For example in earth science they are applied in geology, mining engineering activities, and petroleum. The results produced by the geophysical survey increase the awareness of civil engineers of their wide area of applications. Typical techniques and equipment for marine site investigation. By working at different scales, geophysical methods may be applied to a wide range of investigations from studies of the entire earth global geophysics. Passive and active passive geophysical methods measurements of naturally occurring fields or properties of the earth spatial variations of these fields or properties and attempt to infer something about the subsurface material distibution geology.
Groundwater investigation using geophysical methods. Geological site investigation civil engineering notes. Surface geophysical methods for detection of underground mine workings by william j. We routinely apply state of the art geophysical instrumentation to the. View groundwater investigation using geophysical methods research papers on academia. Active and passive methods geophysical methods can be classified into one of two types. Geophysical survey involving electrical resistivity methods has been carried out at annunciation. The combined use of a geophysical investigation with direct observation is a robust approach to developing an accurate ground model for a project. Therefore, we believe that this study represents a snap shot in time of a changing industry. Geophysical method an overview sciencedirect topics. The second part covers various aspects of ground instrumentation and sensors for the.
Geophysical investigations in environmental studies. Geophysical and geotechnical investigation methodology. Pdf geophysical investigation using resistivity and gpr. Geophysical and geotechnical methods for fluvial levee. Pdf the use of geophysical investigation techniques in the. A geophysical investigation involving the vertical electrical sounding ves electrical resistivity methods was carried out around pydibhimavaram industrial area srikakulam district andhra pradesh. Department of physics, university of adoekiti, ekiti state. The shallow subsurface structure of the earth is important to understand for many economic and safety reasons. Some geophysical methods, such as gamma ray spectrometry and remote sensing, measure surface attributes.
Application of geophysical and geotechnical methods to site. Hill, 3rd edition blackwell science, 2002, isbn0632049294, cost new. Test areas were identical for each of the methods under investigation geophysical survey, coring, and trenching at each locale. A magnetic compass was used in sweden in the mid1600s to find iron ore deposits. Geophysical method of investigating groundwater and sub. Geophysical method of investigating groundwater and subsoil. Geophysical investigation of the permanent site of federal university, dutsinma located in katsina state site was carried out with the objective of investigating the subsoil conditions based on geophysical site exploration methodology. Relative accuracies of different methods of surveying gravity. A comparative overview of geophysical methods kamil erkan division of geodesy and geospatial science school of earth sciences the ohio state university, columbus, oh 43210 erkan. Geophysical methods in exploration and mineral environmental.
Geophysical investigation for groundwater using electrical resistivity method a case study of annunciation grammar school, ikere lga, ekiti state, southwestern nigeria lateef t. This was aimed at evaluating the subsoil conditions and groundwater quality of the area three years after the postspill cleanup exercise. Clark bay geophysical associates, traverse city, mi abstract efforts to delineate underground mine workings in the vicinity of tailings impoundments has. Geophysical manual a practical engineering solutions for highway related problems designed on solving engineering problems using various geophysical methods and techniques geophysical workshop increase confidence and familiarize highway engineers with geophysical technologies for transportation projects. However, geophysical investigations do not necessarily include ert and can combine specific methods according to the purpose of the study. Geophysical and geotechnical investigation methodology assessment for siting. Geophysical choices for karst investigations page 4 of 10 features within the bedrock than available with many other geophysical methods. Application of geophysical methods for site characterization. Several geological, hydrogeological and geophysical methods are. Surface geophysical methods are generally nonintrusive and can be employed quickly to collect subsurface data. The company has extensive experience in shallow exploratory geophysics, such as fault and geologic hazards investigations, tank and utility detection, water projects and well sightings, blast and vibration monitoring, archeological investigations, spill and plume mapping, forensic investigations, bedrock. The relevance of different methods of data acquisition. Pdf application of geophysical methods in civil engineering. Guidance on the planning and scopes of work for geophysical and geotechnical investigations, and interpretation of the results.
Planning a geophysical investigation there are a number of surface and borehole geophysical methods available to choose from when planning a geophysical site investigation. Method that requires the input of artificially generated energy, e. Today, a large number of geophysical methods is used, but geoelectrical tomography and seismic refraction methods are. This paper does not repeat geophysical theory of the different technologies that can be found in the nas book, but focuses on our experience with the practical application of some of these methods. All methods are inherently subject to greater averaging and lower resolution as distances between sampling points increase. Several geophysical surveying methods can be used at sea or in the air. Geophysical surveys for the characterization of landfills. The electrical resistivity method is one that has been widely used because of the theoretical, operational and. Geophysical investigations demonstrated the technologys capability to directly detect, or facilitate the detection of, contamination. While surficial investigation will be used for a first hand hazard assessment, it is the underlying geology. Planning and scope of work objectives the objective of the site investigation for a marine pipeline is to obtain sufficient reliable. When selecting a geophysical method, the following should be completed. Pdf use of geophysical methods for soil profile evaluation. To download a pdf file of this report, go to the us department of the interior, bureau of ocean energy.
Water witching is a traditional method adopted by people to detect bore well locations. Mostly, groundwater flo w coincides with the surface drainages. Geophysical techniques have wide range of applications mainly in earth science, marine science, civil engineering and forensic science. Given the relatively small sums of money involved in ground. Potentially applicable geophysical technology the starting point of a geophysical investigation must be basic physics. Designed on using various geophysical methods and techniques for solving engineering problems. Geophysical methods commonly employed for geotechnical site characterization. This section includes references to specific sections which cover the referenced techniques which are covered in greater detail in later sections. Some geophysical methods, such as gammaray spectrometry and remote sensing, measure surface attributes. The lateral extent of the comstock ore body was mapped using selfpotential methods in the 1880s. The indirect methods of subsurface explorations are used extensively and involve application of geophysical techniques for obtaining fairly accurate idea of subsurface geology. This circular was initiated by khamis haramy, central federal lands highway division.
Geophysical investigation at hazardous waste sites. The acquisitions can be carried out from the surface or with several boreholes techniques. In this paper the important role of the geophysical methods is demonstrated through case studies, and how the geotechnical and geophysical techniques should be. Surface geophysical investigations introduction surface geophysical surveys have been applied to mineral and petroleum exploration for many years. They can be used later in the investigation to confirm and. Regarding the levee problematic, we can briefly distinguish these. Geophysical investigation for groundwater using electrical. Geophysical investigation of the earth involves taking measurement at or near the earths surface that are influence by the internal distribution of physical properties. The scope of investigation, types of methods and techniques generally depend on exploration objectives, available resources, geological and topographical conditions. Electrical resistivity surveys were carried out at a site of shallow hydrocarbon contamination in ahoada, southsouth nigeria. These methods include, in order of increasing subsurface impact, geophysical survey remote sensing, coring and augering, and backhoe trenching. Geophysical methods commonly employed for geotechnical site.
Adedoyin1 abstract an integrated geophysical and geotechnical survey was carried out in a proposed engineering site at ikoyi, lagos, nigeria. Groundwater investigation using geophysical methods research. Geophysical investigation geophysical methods comprise of measurement of signals from natural or induced phenomena of physical properties of sub surface formation. Geophysical methods of groundwater exploration electrical resistivity method, seismic refraction method, determination of aquifer thickness, determination of top of the sloping aquifer 3. Geophysical methods commonly employed for geotechnical. Geophysical methods can be helpful in mapping areas of contaminated soil and groundwater. Site investigation methods for seismic reflection surveying, seismic data processing, and measuring dynamic soil properties are among the most rapidly evolving areas for the industry. Three subsurface testing methods were independently applied to the six test locales to assess their utility for buried site discovery. Unfortunately, this book cant be printed from the openbook. Application of geophysical and geotechnical methods to. The higher capital and operating costs associated with marine or airborne work are offset by the increased speed of operation and the bene. Subsurface surveys extensive education and experience in implementing state oftheart techniques allows for a more comprehensive approach to solving. A geophysical investigation was performed to evaluate the effectiveness of three geophysical methods electrical resistivity imaging eri, seismic refraction sr, and multiplechannel analysis.
Vertical electrical sounding ves using schlumberger array was conducted at thirteen ves stations. The discipline of environmental geophysics needs to bring to the attention of policy makers and planners. Resistivity methods environmental geophysics us epa. Geophysical methods in exploration and mineral environmental investigations by donald b. Subsurface surveys, an applied geophysics company, uses a variety of geophysical methods to solve engineering, geological, environmental and forensic problems. Gravity prospecting can be used where density contrasts are present in a geological structure, and the usual approach is to measure differences in gravity from place to place. Geophysical measurements are conducted from the surface of the ground, in wells, excavations or in combination of locations where sources and detectors are placed. Rsk geophysics provide consultancy, survey design and site investigation services. This website beta version contains information on geophysical methods, references to geophysical citations, and a glossary of geophysical terms related to environmental applications. The magnetic and gravitational fields emanating from the earths interior hold essential information concerning seismic activities and the internal structure. Chapter two geophysical methods use of geophysics for. When performed properly and utilized early in the site characterization process, the methods can provide valuable information for placing monitoring wells and borings.
Groundbased methods will be applied to very specific problems or studies requiring great detail. Exploring the ground water by geophysical method is termed ground. Geophysical survey is the systematic collection of geophysical data for spatial studies. Geophysical techniques offer the chance to overcome some of the problems inherent in more conventional ground investigation techniques. It should be understood that geophysical equipment alone will not provide the detailed conclusive data needed on geologic condi tions and engineering interpretations.