Page 8 - The Geological Interpretation of Well Logs

Chapter 7 The gamma ray and spectral gamma ray logs 67
7.1 Generalities 67
7.2 Natural gamma radiation 69
7.3 Tools 70
7.4 Log characteristics TI
7.5 Geochemical] behaviour of potassium, thorium and uranium
and natural radioactivity 74
7.6 Radioactivity of shales and clays 17
7.7 Quantitative use of the simple gamma ray log 78
7.8 Qualitative use of the simple gamma ray log 79
7.9 Quantitative use of the spectral gamma ray log 85
7.10 Qualitative and semi-quantitative uses of the spectral gamma ray log 86

Chapter 8 Sonic or acoustic logs 91
8.1 Generalities 91
8.2 Pnnciples of measurement 92
8.3 Tools 92
8.4 Log charactenstics 95
8.5 Quantitative uses 97
8.6 Qualitative uses 98
8.7 Seismic applications of the sonic log 107
8.8 Full waveform acoustic logs (array sonic) 109

Chapter 9 The density and photoelectric factor logs 115
9,1 The density log, generalities 113
9.2 Principles of measurement 116
9.3 Tools 116
9.4 Log characteristics 118
9.5 Quantitative uses 119
9.6 Qualitative uses © 121
THE PHOTOELECTRIC FACTOR LOG (OR LITHO-DENSITY) 127
9.7 Generalities 127
9.8 Principles of measurement 129
9.9 Log characteristics 130
9.10 Quantitative uses 130
9.11 Qualitative uses 131

Chapter 10 The neutron log 133
10.1 Generalities 133
10.2 Principles of measurement 134
10.3 Tools 135
10.4 Log characteristics 138
10.5 Quantitative uses 138
10.6 Qualitative uses 141
10.7 Neutron-density combination: lithology identification 147

Chapter 11 Lithology reconstruction from logs 151
11.1 Introduction 151
11.2 Litholgy from drill data - the mud log 151
11.3 Lithology from cores - direct physical sampling 153
11.4 Lithology interpretation from wireline logs — manual method 155
11.5 Computer aids to lithology interpretation 159
11.6 Multi-log quantification of lithology 165

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