Overvoltage Research and Geophysical Applications (eBook)

International Series of Monographs on Earth Sciences

James R. Wait (Herausgeber)

eBook Download: PDF

2013 | 1. Auflage
166 Seiten
Elsevier Science (Verlag)
978-1-4831-5131-1 (ISBN)

Infos

Overvoltage Research and Geophysical Applications deals with the subject of overvoltage (or induced electrical polarization) as it relates to geophysical exploration. This book presents the results of theoretical and experimental research conducted between 1946 and 1958 to investigate overvoltage and sponsored by Newmont Mining Corporation. This book is comprised of 10 chapters and begins with a brief overview of the history of Newmont's interest in overvoltage. The next chapter describes a theory for induced polarization effects (for step-function excitation), with particular reference to a mathematical formulation that represents the volume distribution of dipolar sources. The reader is then introduced to a brief theoretical derivation for the effective conductivity and dielectric constant of a homogeneous medium loaded with a uniform distribution of spherical conducting particles. The following chapters explore the complex conductivity of rocks as a function of frequency; laboratory studies of induced polarization in mineralized and non-mineralized rock specimens; induced polarization decay curves on rock specimens; and phenomena resulting from electric polarization of rocks at low frequencies. Some electrical transient measurements on igneous, sedimentary, and metamorphic rocks are presented. The final chapter considers various explanations of the normal effect and describes induced-polarization experiments. This monograph will be of interest to geophysicists.

Inhalt

Front Cover 1
Overvoltage Research and Geophysical Applications 4
Copyright Page 5
Table of Contents 6
PREFACE 8
CHAPTER 1. HISTORICAL SUMMARY OF OVERVOLTAGE DEVELOPMENTS BY NEWMONT EXPLORATION LIMITED, 1946-1955 10
REFERENCES 12
CHAPTER 2. A THEORY OF INDUCED POLARIZATION EFFECTS (FOR STEP-FUNCTION EXCITATION) 13
INTRODUCTION 13
MATHEMATICAL FORMULATION OF THE DYNAMIC DIPOLAR REPRESENTATION 14
SPECIFIC CASES 17
REFERENCES 30
CHAPTER 3. A PHENOMENOLOGICAL THEORY OF OVERVOLTAGE FOR METALLIC PARTICLES 31
INTRODUCTION 31
BASIC CONSIDERATIONS 31
TRANSIENT RESPONSE 34
REFERENCES 37
CHAPTER 4. THE VARIABLE-FREQUENCY METHOD 38
I. FUNDAMENTAL CONSIDERATIONS 38
II. LINE COUPLING EFFECTS 48
III. GENERAL DESCRIPTION OF RESULTS 54
REFERENCES 58
CHAPTER 5. LABORATORY INVESTIGATION OF OVERVOLTAGE 59
INTRODUCTION 59
EXPERIMENTAL PROCEDURE 59
SOME THEORETICAL CONSIDERATIONS 64
SOME LABORATORY RESULTS 66
INVESTIGATIONS ON STANDARD SAMPLES 67
CHAPTER 6A. CRITERIA FROM THE TRANSIENT DECAY CURVES 80
SUMMARY OF RESULTS OF THE DERIVATIVE CRITERIA 82
CONCLUDING REMARKS 83
CHAPTER 6B. ANALYSIS OF THE FREQUENCY RESPONSE DATA 93
CHAPTER 7. ANALYSIS OF SOME ELECTRICAL TRANSIENT MEASUREMENTS ON IGNEOUS, SEDIMENTARY AND METAMORPHIC ROCKS 101
INTRODUCTION 101
FORM OF THE NEWMONT DATA 101
REVIEW OF POLARIZATION THEORY 102
EVALUATION OF NEWMONT DATA 109
SUMMARY AND CONCLUSIONS 114
REFERENCES 120
CHAPTER 8. FIELD EQUIPMENT FOR PROSPECTING BY THE OVERVOLTAGE METHOD 121
CHAPTER 9. OVERVOLTAGE FIELD RESULTS 124
OVERVOLTAGE FIELD RESULTS 124
CHAPTER 10A. THE NORMAL EFFECT—PART I 134
I. INTRODUCTION 134
II. EXPERIMENTAL 138
III. RESULTS AND DISCUSSION 147
IV. CONCLUSIONS 150
REFERENCES 150
CHAPTER 10B. THE NORMAL EFFECT—PART II 151
I. INTRODUCTION 151
II. EXPERIMENTAL 154
III. RESULTS AND DISCUSSION 162
IV. CONCLUSIONS 167
REFERENCES 167

Produkt-Details

• Erscheint lt. Verlag: 22.10.2013
• Sprache: englisch
• Themenwelt: Naturwissenschaften ► Geowissenschaften ► Geologie
• Themenwelt: Technik ► Bergbau
• ISBN-10: 1-4831-5131-X / 148315131X
• ISBN-13: 978-1-4831-5131-1 / 9781483151311