Geophysical Methods for Geologists, Environmental Scientists and Civil Engineers

Chapter 1Introduction: Philosophy and basic principlesA practical manual for engineers, environmental scientists and geologists: the book shows how to decide if a geophysical survey is a cost-effective method for solving a sub-surface problem, how to choose which method to use, how to quality assure the results and how to assess the validity of the interpretation.The geological, environmental and engineering problems that geophysics can help to solve - and those which it cannot!The trade-off between resolution and depth of imagingDefining the reliability of the sub-surface image Chapter 2Physical properties of rocks and sediments: these are what makes geophysics work!Exploring the ranges of the physical properties of rocks and sediments and their sensitivity to the geophysical methods which can resolve them: the solid matrix, the plastic (clay) component and the fluid component of rocksChapter 3Geophysical surveying methods for different environments: these are the methods which are available to you!Airborne techniquesSurface techniquesThe land surfaceRiver and flood plainBeach and inter-tidal zone Shallow marineDeep seaSub-surface techniquesBorehole loggingBorehole-to-borehole measurements Vertical seismic profilingChapter 4Specification and implementation of the geophysical survey: how to choose the correct method and keep a close eye on the contractorsDefining the environmental or engineering problemAnalysing the physical properties, dimensions and depths of burial of the sub-surface targetsIs a geophysical technique appropriate? It may be more cost-effective to auger or drill a few boreholes!Using interactive spreadsheets to define appropriate geophysical methods for the target Designing the size and sampling interval of the surveyCosting the surveySupervising the field acquisitionQuality assurance of the raw field dataChapter 5Processing the raw field dataHow to remove interference which degrades the quality and accuracy of the target geophysical data Quality assurance of processing: have the geophysical data been under- or over-processed?Chapter 5 Inversion of the survey: the geophysical model What does inversion mean?Commercial computer inversion packagesStraightforward EXCEL inversion routinesSimple rules-of-thumb for checking computer inversionHow to assess the accuracy, stability and resolution of the inversionChapter 6Turning the geophysical model into a geological, environmental or engineering solutionDetermining the sub-surface physical/geological/engineering relationshipsAssessing the reliability, stability and accuracy of the relationshipsVisualisation of the geological/environmental/engineering solutionAssessing the stability, reliability and accuracy of the solutionChapter 7Imaging sub-surface rocks - principles and short case historiesGeological mappingSite investigationRock mass assessmentLocation of natural cavities and mineshaftsCoastal and near-shore investigationsArchaeological InvestigationsChapter 8Imaging fluids within the rocks - principles and short case histories Groundwater explorationGroundwater pollutionLandfill sites: location, consolidation of the fill, leakage of leachates, gas detection.Derelict and contaminated land assessment. Investigations in urban areas.Chapter 9Full case histories - from the initial problem to the final reportBath Spa Thermal Water ProjectA case study of an integrated geophysical survey from the initial meeting of client and consultants to the presentation of the final report to the client and a public meeting.Additional Case Histories from USA and CanadaChapter 10Future trends in exploration geophysics: the developments we expect (hope!) will come on-stream during the next ten years.ReferencesAppendix 1 Specification and Implementation of a Geophysical SurveyMcCann, David is the author of 'Geophysical Methods for Geologists, Environmental Scientists and Civil Engineers', published 2010 under ISBN 9781405109253 and ISBN 1405109254.