Lýsing:
Looking Into the Earth comprehensively describes the principles and applications of both 'global' and 'exploration' geophysics on all scales. It forms an introduction to geophysics suitable for those who do not necessarily intend to become professional geophysicists, including geologists, civil engineers, environmental scientists, and field archaeologists. The book is organised into two parts: Part 1 describes the geophysical methods, while Part 2 illustrates their use in a number of extended case histories.
Mathematical and physical principles are introduced at an elementary level, and then developed as necessary. Student questions and exercises are included at the end of each chapter. The book is aimed primarily at introductory and intermediate university students taking courses in geology, earth science, environmental science, and engineering. It will also form an excellent introductory textbook in geophysics departments, and will help practising geologists, archaeologists and engineers understand what geophysics can offer their work.
Annað
- Höfundar: Alan E. Mussett, M. Aftab Khan
- Útgáfa:1
- Útgáfudagur: 2000-10-23
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- Format:ePub
- ISBN 13: 9781139636780
- Print ISBN: 9780521785747
- ISBN 10: 1139636782
Efnisyfirlit
- Cover
- Title Page
- Copyright
- Contents
- Preface: Turning a Magician into an Expert
- Acknowledgements
- Chapter 1: Introducing Geophysics and This Book
- 1.1 What is geophysics?
- 1.2 The Earth through geophysical spectacles: The relation of geophysics to geology
- 1.3 What this book covers and how it is structured
- Summary
- Further reading
- Part I: Geophysical Methods
- Subpart I.1: Data Acquisition and Processing
- Chapter 2: Data Acquisition and Reduction: Carrying out a Geophysical Survey
- 2.1 Data acquisition: Taking measurements
- 2.2 Data reduction
- 2.3 Signal and noise
- 2.4 Modelling
- 2.5 Geological interpretation
- 2.6 Displaying the results
- Summary
- Further reading
- Problems
- Chapter 3: Data Processing: Getting More Information from the Data
- 3.1 Fourier analysis
- 3.1.1 Wavelength
- 3.1.2 Harmonic analysis
- 3.1.3 Fourier analysis of a profile
- 3.1.4 Fourier analysis in 2D: Gridded data
- 3.1.5 Why a harmonic series?
- 3.2 Digital filtering
- 3.2.1 Simple filters
- 3.2.2 Aliasing
- 3.2.3 Designing a simple filter
- 3.2.4 Filtering in 2D: Gridded data
- 3.2.5 Using filters to enhance various types of features
- 3.3 Summing up: Fourier analysis and filtering
- Summary
- Further reading
- Problems
- 3.1 Fourier analysis
- Chapter 2: Data Acquisition and Reduction: Carrying out a Geophysical Survey
- Subpart I.1: Data Acquisition and Processing
- Subpart I.2: Seismology
- Chapter 4: Global Seismology and Seismic Waves
- 4.1 Waves, pulses, and rays
- 4.2 Detecting seismic waves: Seismometers and geophones
- 4.3 The Earth is concentrically layered
- 4.3.1 Spherical symmetry of the Earth’s interior
- 4.3.2 Concentric layering
- 4.4 Finding the path of a ray through the Earth
- 4.4.1 Refraction: Snell’s law
- 4.4.2 Tracing rays through the Earth: The ray parameter, p
- 4.4.3 Ray tracing and the Earth’s velocity–depth structure
- 4.5 Seismic features of the Earth
- 4.5.1 Core and mantle
- 4.5.2 Longitudinal and transverse waves
- 4.5.3 The mantle–core difference
- 4.5.4 Other seismological features of the Earth
- 4.5.5 Attenuation
- 4.5.6 Ray paths in the Earth
- 4.6 Seismic tomography
- Summary
- Further reading
- Problems
- Chapter 5: Earthquakes and Seismotectonics
- 5.1 What is an earthquake?
- 5.2 Locating an earthquake
- 5.3 Fault-plane solutions and stresses
- 5.3.1 Fault-plane solutions
- 5.3.2 The earthquake stress field and the double-couple mechanism
- 5.4 Rupture dimensions and displacements
- 5.5 Measures of earthquake size
- 5.5.1 Intensity: Severity of an earthquake at a locality
- 5.5.2 Seismic moment: Size of the earthquake at source
- 5.6 Seismotectonics: Deducing tectonic processes
- 5.6.1 Qualitative seismotectonics
- 5.6.2 Quantitative seismotectonics: Seismic and aseismic faulting
- 5.7 Surface waves
- 5.8 Magnitude: Another measure of earthquake strength
- 5.9 Energies of earthquakes
- 5.10 Earthquake damage and its mitigation
- 5.10.1 Causes of damage
- 5.10.2 Mitigating the damage caused by earthquakes
- Summary
- Further reading
- Problems
- Chapter 6: Refraction Seismology
- 6.1 Critical refraction and head waves
- 6.1.1 Huygens’s wavelets
- 6.1.2 Head waves
- 6.2 The time–distance (t–x) diagram
- 6.3 Multiple layers
- 6.4 Dipping interfaces
- 6.5 Seismic velocities in rocks
- 6.6 Hidden layers
- 6.6.1 Hidden layer proper
- 6.6.2 Low-velocity layer
- 6.7 Carrying out a seismic-refraction survey
- 6.8 Undulating interfaces and delay times
- 6.8.1 Delay times
- 6.8.2 The plus–minus method
- 6.9 Ray tracing and synthetic seismograms
- 6.10 Detecting offsets in interfaces
- 6.11 Fan shooting: Simple seismic tomography
- Summary
- Further reading
- Problems
- 6.1 Critical refraction and head waves
- Chapter 7: Reflection Seismology
- 7.1 Seismic-reflection sections and their limitations
- 7.2 Velocity determination using normal moveout, NMO
- 7.3 Stacking
- 7.4 Dipping reflectors and migration
- 7.5 Faulted reflectors: Diffraction
- 7.6 Multiple reflections
- 7.7 Carrying out a reflection survey
- 7.7.1 Data acquisition
- 7.7.2 Common-depth-point (CDP) stacking
- 7.7.3 Data display
- 7.7.4 Vibroseis: A nonimpulsive source
- 7.8 What is a reflector?
- 7.8.1 Strengths of reflected and transmitted pulses
- 7.8.2 Vertical resolution: The least separation at which interfaces can be distinguished
- 7.8.3 Synthetic reflection seismograms
- 7.9 Three-dimensional (3D) surveying
- 7.10 Reflection seismology and the search for hydrocarbons
- 7.10.1 The formation of hydrocarbon traps
- 7.10.2 The recognition of hydrocarbon traps
- 7.11 Sequence stratigraphy
- 7.12 Shallow-reflection seismic surveys
- Summary
- Further reading
- Problems
- Chapter 4: Global Seismology and Seismic Waves
- Chapter 8: Gravity on a Small Scale
- 8.1 Newton’s Law of Gravitation
- 8.1.1 The mass of the Earth
- 8.2 Densities of rocks
- 8.3 Gravity units
- 8.4 Gravity anomalies of some bodies
- 8.5 Measuring gravity: Gravimeters
- 8.6 Data reduction
- 8.6.1 Instrumental effects and other corrections
- 8.6.2 Residual and regional anomalies
- 8.7 Planning and carrying out a gravity survey
- 8.8 Modelling and interpretation
- 8.8.1 The inversion problem
- 8.8.2 Depth rules
- 8.8.3 Modelling
- 8.9 Total excess mass
- 8.10 Microgravity surveys
- Summary
- Further reading
- Problems
- 8.1 Newton’s Law of Gravitation
- Chapter 9: Large-Scale Gravity and Isostasy
- 9.1 Isostasy
- 9.1.1 The concept of isostasy: Floating blocks
- 9.1.2 Gravity and isostatic equilibrium
- 9.1.3 Simple isostatic calculations
- 9.1.4 Airy and Pratt models of isostasy
- 9.1.5 Isostasy with regional compensation
- 9.1.6 The isostatic anomaly
- 9.1.7 The evidence for isostasy
- 9.1.8 Isostatic rebound and the viscosity of the asthenosphere
- 9.2 How the mantle is both solid and liquid: Solid-state creep
- 9.3 What is the lithosphere?
- 9.4 Forces on the lithosphere
- 9.5 The shape of the Earth
- 9.5.1 Seeing the ocean floor in the ocean surface
- 9.5.2 The large-scale shape of the Earth
- Summary
- Further reading
- Problems
- 9.1 Isostasy
- Chapter 10: Palaeomagnetism and Mineral Magnetism
- 10.1 The Earth’s magnetic field, present and past
- 10.1.1 Magnets and magnetic fields
- 10.1.2 The Earth’s magnetic field at present
- 10.1.3 The Earth’s magnetic field in the past
- 10.2 Palaeomagnetism
- 10.2.1 Measuring a palaeomagnetic direction
- 10.2.2 Palaeopoles, palaeolatitudes, and rotations
- 10.2.3 Apparent polar wander (APW) paths and relative continental movements
- 10.3 The magnetism of rocks
- 10.3.1 The atomic nature of magnetisation
- 10.3.2 Magnetic domains
- 10.3.3 Curie and blocking temperatures
- 10.3.4 Thermal remanent magnetisation (TRM)
- 10.3.5 Magnetic minerals
- 10.3.6 Mechanisms that magnetise rocks at ambient temperature
- 10.4 Testing when the remanence was acquired
- 10.4.1 Laboratory tests
- 10.4.2 Field tests
- 10.5 Magnetostratigraphy
- 10.5.1 The magnetic polarity timescale
- 10.5.2 Magnetic polarity stratigraphy
- 10.5.3 Magnetic stratigraphy utilising secular variation and excursions
- 10.6 Mineral magnetism
- 10.7 Magnetic fabric: Susceptibility anisotropy
- Summary
- Further reading
- Problems
- 10.1 The Earth’s magnetic field, present and past
- Chapter 11: Magnetic Surveying
- 11.1 Magnetic surveying
- 11.1.1 Anomaly of a buried magnet
- 11.1.2 Magnetometers
- 11.1.3 Data acquisition
- 11.1.4 Data reduction
- 11.2 Anomalies of some simply shaped bodies
- 11.2.1 Magnetic poles and fields
- 11.2.2 The field of a dipole
- 11.2.3 Anomaly of a dipole, or small body
- 11.2.4 Anomaly of a sphere
- 11.2.5 Anomaly of a vertical sheet
- 11.3 Depth of the body
- 11.4 Remanent and induced magnetisation
- 11.5 Computer modelling
- 11.6 More advanced processing of data
- 11.6.1 Reduction to the pole
- 11.6.2 Pseudogravity
- 11.6.3 Upward and downward continuation
- 11.7 Magnetic gradiometry
- 11.8 The Blairgowrie magnetic anomaly: A case study
- Summary
- Further reading
- Problems
- 11.1 Magnetic surveying
- Chapter 12: Resistivity Methods
- 12.1 Basic electrical quantities
- 12.2 Resistivity surveying
- 12.2.1 Resistivities of rocks and minerals
- 12.2.2 How electricity flows through rocks
- 12.2.3 The need for four electrodes
- 12.3 Vertical electric sounding, VES: Measuring layered structures
- 12.3.1 The basic concept
- 12.3.2 Refraction of current paths
- 12.3.3 Apparent resistivity
- 12.3.4 Carrying out a Wenner VES survey
- 12.3.5 Modelling the data
- 12.3.6 Other electrode arrays
- 12.3.7 Limitations of vertical electrical sounding
- 12.4 Resistivity profiling: Detecting lateral variations
- 12.4.1 Introduction
- 12.4.2 Some arrays for profiling
- 12.5 Electrical imaging
- 12.6 Designing and interpreting a resistivity survey
- 12.6.1 Choosing a resistivity array
- 12.6.2 Geological interpretation
- Summary
- Further reading
- Problems
- Chapter 13: Induced Polarisation and Self-Potential
- 13.1 Induced polarization, IP
- 13.1.1 What induced polarization is
- 13.1.2 Carrying out an IP survey
- 13.1.3 Data reduction and display
- 13.2 Self-potential, SP
- 13.2.1 What self-potential is
- 13.2.2 SP surveying
- Summary
- Further reading
- Problems
- 13.1 Induced polarization, IP
- Chapter 14: Electromagnetic Methods
- 14.1 Basic concepts
- 14.1.1 Electromagnetic induction
- 14.1.2 Factors that affect the signal
- 14.2 Some e-m systems
- 14.2.1 Moving transmitter–plus–receiver system (Slingram)
- 14.2.2 Turam system
- 14.3 Transient electromagnetic, TEM, systems
- 14.3.1 The basic concept
- 14.3.2 The INPUT system
- 14.4 Electromagnetic waves
- 14.4.1 Wavelengths
- 14.4.2 Absorption and attenuation of e-m waves
- 14.5 VLF (very-low-frequency) method
- 14.5.1 Basic concepts
- 14.5.2 Carrying out a VLF survey
- 14.6 Phase
- 14.7 Magnetotelluric, MT, surveying: Looking into the deep crust and mantle
- 14.7.1 Basic concepts
- 14.7.2 Carrying out an MT survey
- 14.8 Ground-penetrating radar, GPR
- 14.8.1 How ground-penetrating radar works
- 14.8.2 Velocity, reflection, penetration, and resolution
- 14.8.3 Data reduction
- 14.8.4 Uses of GPR surveys
- Summary
- Further reading
- Problems
- 14.1 Basic concepts
- Chapter 15: The Ages of Rocks and Minerals: Radiometric Dating
- 15.1 The atomic clock
- 15.2 The uranium–lead (U–Pb) dating method
- 15.3 Assumptions of the Basic Dating Equation
- 15.4 The potassium-argon (K-Ar) dating method
- 15.4.1 The conventional K–Ar method
- 15.4.2 The argon-argon (Ar–Ar) method
- 15.5 The rubidium–strontium (Rb–Sr) dating method
- 15.6 The samarium–neodymium (Sm–Nd) dating method
- 15.7 The lead–lead (Pb–Pb) dating method
- 15.7.1 Theory of the method
- 15.7.2 The ‘age of the Earth’
- 15.8 Fission-track (FT) dating
- 15.9 What event is being dated?
- 15.9.1 Diffusion
- 15.9.2 Closure temperature
- 15.9.3 Cooling histories
- 15.9.4 Two dates from a single rock, using the Rb–Sr method
- 15.9.5 Two dates from a single rock, using the U–Pb discordia method
- 15.9.6 Dating palaeomagnetism of slowly cooled regions
- 15.10 Dating sedimentary rocks
- 15.11 The geological time scale
- 15.12 Dating young rocks
- 15.12.1 Uranium-series disequilibrium methods
- 15.12.2 Carbon-14 (14C) and other dating methods using cosmogenic isotopes
- 15.13 Why so many radiometric dating methods?
- Summary
- Further reading
- Problems
- Chapter 16: Radioactive Surveying
- 16.1 Radioactive radiations
- 16.2 γ ray surveys
- 16.2.1 Measurement: The γ ray spectrometer
- 16.2.2 Carrying out a γ ray survey
- 16.2.3 Geological mapping
- 16.3 Radon monitoring
- Summary
- Further reading
- Problems
- Chapter 17: Geothermics: Heat and Temperature in the Earth
- 17.1 Basic ideas in geothermics
- 17.1.1 Introduction
- 17.1.2 Temperature and heat
- 17.1.3 How heat travels: Conduction and convection
- 17.1.4 Convection and conduction within the Earth
- 17.2 Heat flow and temperature
- 17.2.1 Measurement of heat flux
- 17.2.2 Oceanic lithosphere
- 17.2.3 Continental lithosphere and radioactivity
- 17.3 Effects of changes to the lithosphere
- 17.3.1 Thermal capacity
- 17.3.2 Filling of a sedimentary basin
- 17.3.3 Overthrusting and underthrusting
- 17.3.4 Crustal thickening and orogenies
- 17.4 Global heat flow and geothermal energy
- 17.4.1 Global heat flow
- 17.4.2 Sources of the Earth’s heat
- 17.4.3 Geothermal energy
- 17.5 The effect of surface temperature changes: A record of past climates
- Summary
- Further reading
- Problems
- 17.1 Basic ideas in geothermics
- Chapter 18: Well Logging and Other Subsurface Geophysics
- 18.1 Introduction
- 18.2 Drilling and its effects on the formations
- 18.3 Sources of information from a borehole: Logs
- 18.4 Geophysical well logging in the oil industry
- 18.5 The most commonly used logs
- 18.5.1 The measurement of strata dip, borehole inclination, and diameter
- 18.5.2 The self-potential log
- 18.5.3 Resistivity logs
- 18.5.4 Radioactivity logs
- 18.5.5 The sonic log
- 18.5.6 The temperature log
- 18.5.7 Cross plots
- 18.6 Geophysical logging outside the oil industry
- 18.6.1 Mineral exploration
- 18.6.2 Magnetic logs
- 18.6.3 The IP–resistivity log
- 18.7 Other well-logging applications
- 18.8 Other subsurface geophysics
- Summary
- Further reading
- Problems
- Chapter 19: Which Geophysical Methods to Use?
- 19.1 Introduction
- 19.2 Does the problem have geophysical expression?
- 19.3 Is the variation lateral or vertical?
- 19.4 Is the signal detectable?
- 19.5 Will the result be clear enough to be useful?
- 19.6 Is a survey practicable?
- Problems
- Chapter 20: Global Tectonics
- 20.1 The basic concept of plate tectonics
- 20.2 Divergent, or constructive, margins
- 20.2.1 Ocean-floor magnetic anomalies
- 20.2.2 The shape of spreading ridges
- 20.3 Conservative margins
- 20.4 Convergent, or destructive, margins
- 20.4.1 Ocean–ocean convergent margins and subduction zones
- 20.4.2 Ocean–continent convergent margins
- 20.4.3 Continent–continent convergent margins
- 20.5 The geometry of plate tectonics
- 20.5.1 Poles of rotation
- 20.5.2 Triple junctions and plate evolution
- 20.6 The globe according to plate tectonics
- 20.7 Continental positions in the past
- 20.8 Crust formation at ridges
- 20.9 What moves the plates?
- 20.9.1 Forces on plates
- 20.9.2 The hot-spot frame of reference: Plate velocities
- 20.9.3 Deducing the dominant drive forces
- 20.9.4 Plate tectonics and mantle convection
- Summary
- Further Reading
- Problems
- Chapter 21: Is the Kenya Rift a New Plate Margin? A Regional Geophysical Study
- 21.1 Introduction: The East African Rift System
- 21.2 Morphology and geology of the Kenya Rift
- 21.3 Gravity studies
- 21.4 Seismic surveys
- 21.4.1 The seismicity of Kenya
- 21.4.2 Teleseismic studies
- 21.4.3 Seismic refraction and wide-angle reflection surveys
- 21.5 Combined seismic and gravity models
- 21.6 Heat flow studies
- 21.7 Electrical conductivity
- 21.8 Summary
- Further reading
- Chapter 22: Hydrocarbon Exploration
- 22.1 Introduction: Energy sources and the demand for hydrocarbons
- 22.2 The origin and accumulation of hydrocarbons
- 22.3 Where sedimentary basins form
- 22.4 Exploration for petroleum
- 22.5 The West Sole gas field of the southern North Sea: A case study
- 22.6 The Forties oil field of the northern North Sea: A case study
- 22.6.1 Discovery and initial development of the field
- 22.6.2 Further development of the Forties field
- 22.7 The future
- Further reading
- Chapter 23: Exploration for Metalliferous Ores
- 23.1 Introduction: Metalliferous and other ore deposits
- 23.2 The formation of ores and their geophysical properties
- 23.3 Where ores form
- 23.4 Exploration for orebodies
- 23.5 The Elura Orebody, New South Wales, Australia: A case study
- 23.5.1 Background and reconnaissance surveys
- 23.5.2 Initial surveys of the Elura orebody
- 23.5.3 Evaluation of the deposit
- 23.5.4 Assessment of geophysical surveying methods
- Further reading
- Chapter 24: Volcanoes
- 24.1 Introduction: Types of eruption and damage
- 24.2 Methods for investigating volcanoes and monitoring activity
- 24.3 The 1989–1990 eruption of Redoubt Volcano, Alaska: A case study
- 24.3.1 Background
- 24.3.2 The 1989–1990 eruption
- 24.3.3 Monitoring of activity
- 24.4 Etna lava eruptions 1991–1993: A case study
- 24.4.1 Background
- 24.4.2 Deformation and microgravity
- 24.4.3 The 1991–1993 eruption
- Further reading
- Chapter 25: The Chicxulub Structure and the K/T Mass Extinction
- 25.1 Introduction
- 25.2 Impacts and craters
- 25.3 The Chicxulub structure
- 25.3.1 Background
- 25.3.2 The structure of Chicxulub
- 25.3.3 Ages of the Chicxulub structure and ejecta
- 25.3.4 The Manson Crater
- 25.4 Giant eruptions
- 25.5 Conclusions to date
- Further reading
- Chapter 26: Hydrogeology and Contaminated Land
- 26.1 Introduction
- 26.2 Aquifers
- 26.3 Geophysical methods useful in hydrogeology
- 26.4 GPR surveying of the water table, the Netherlands: An example
- 26.4.1 Background
- 26.4.2 Offsets of the water table
- 26.5 Structural control of aquifers in East Anglia, England: A case study
- 26.5.1 Introduction
- 26.5.2 Geophysical surveys
- 26.6 Saline contamination of the Crag aquifer, East Anglia: A case study
- 26.6.1 Background
- 26.6.2 Geophysical surveys
- 26.7 Landfill sites and contaminated ground
- 26.7.1 Introduction
- 26.7.2 Investigation of a landfill in northern England: A case study
- 26.7.3 Landfill monitoring: A case study
- Further reading
- Chapter 27: Location of Cavities and Voids
- 27.1 Introduction
- 27.2 Possible geophysical techniques for locating cavities
- 27.2.1 Seismic methods
- 27.2.2 Electrical methods
- 27.2.3 Magnetic methods
- 27.2.4 Gravity methods
- 27.2.5 Fracturing around cavities
- 27.3 Collapses in buried karstic terrain, Kuwait: A case study
- 27.3.1 Background
- 27.3.2 Gravity survey
- 27.4 Land reclamation, south Wales: A case study
- 27.4.1 Background
- 27.4.2 Gravity survey
- Further reading
- Chapter 28: Archaeological Site Surveying
- 28.1 Site surveying
- 28.2 Archaeological features and their geophysical expression
- 28.2.1 Ditches, pits, and postholes
- 28.2.2 Foundations
- 28.2.3 Furnaces, fireplaces, and kilns
- 28.3 Geophysical methods useful for archaeological surveying
- 28.3.1 Magnetic and susceptibility surveys
- 28.3.2 Resistivity surveys
- 28.3.3 Ground-penetrating radar (GPR)
- 28.3.4 Other techniques
- 28.3.5 Display of data
- 28.4 A possible Roman villa: A case study
- 28.4.1 Background
- 28.4.2 Geophysical surveys
- 28.5 Hudson’s Bay Company fur trade post: A case study
- 28.5.1 Background
- 28.5.2 Geophysical surveys
- Further reading
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