GEOLOGY OF CARBONATE RESERVOIRS......Page 4
CONTENTS......Page 8
PREFACE......Page 14
ABOUT THIS BOOK......Page 18
1 INTRODUCTION......Page 20
1.1.1 Carbonates......Page 21
1.1.2 Reservoirs......Page 23
1.2 Finding and Developing Carbonate Reservoirs......Page 25
1.2.1 Sources of Data on Reservoirs......Page 26
1.3 Unique Attributes of Carbonates......Page 28
Review Questions......Page 31
2.1 Definitions......Page 32
2.2 Fundamental Rock Properties......Page 33
2.2.1 Texture......Page 34
2.2.2 Fabric......Page 37
2.3 Classification of Carbonate Rocks......Page 39
2.3.1 Classification of Detrital Carbonates......Page 46
2.3.2 Classification of Reef Rocks......Page 47
2.4 Dependent or Derived Rock Properties......Page 49
2.4.1 Porosity......Page 50
2.4.1.1 Porosity Classifications......Page 53
2.4.1.2 The Archie Classification......Page 54
2.4.1.3 The Choquette–Pray Classification......Page 55
2.4.1.4 The Lucia Classification......Page 58
2.4.2 A New Genetic Classification for Carbonate Porosity......Page 61
2.4.3 Permeability......Page 63
2.5.1 Borehole Logs and Carbonate Reservoirs......Page 66
2.5.2 Tertiary Rock Properties and the Seismograph......Page 72
Review Questions......Page 73
3.1.1 Saturation......Page 75
3.1.2 Wettability......Page 81
3.1.3 Capillarity......Page 82
3.2 Capillary Pressure and Reservoir Performance......Page 83
3.2.1 Capillary Pressure, Pores, and Pore Throats......Page 85
3.2.2 Converting Air–Mercury Capillary Pressures to Oil–Water Equivalents......Page 88
3.2.4 Evaluating Seal Capacity......Page 89
3.3 Fluid Withdrawal Efficiency......Page 90
Review Questions......Page 93
4 STRATIGRAPHIC PRINCIPLES......Page 95
4.1 Carbonate Depositional Platforms......Page 96
4.1.1 Rimmed and Open Shelves......Page 99
4.1.2 Homoclinal and Distally Steepened Ramps......Page 101
4.2.1 Rock Units......Page 102
4.2.2 Time Units......Page 103
4.3 Correlation......Page 105
4.4 Anatomy of Depositional Units......Page 107
4.4.1 Facies, Successions, and Sequences......Page 110
4.4.2 Environmental Subdivisions and Standard Depositional Successions......Page 112
4.5.1 Definitions and Scales of Observation......Page 118
4.5.3 Sequence Stratigraphy in Exploration and Development......Page 121
Suggestions for Further Reading......Page 123
Review Questions......Page 124
5 DEPOSITIONAL CARBONATE RESERVOIRS......Page 125
5.1 Depositional Porosity......Page 127
5.2 Depositional Environments and Processes......Page 128
5.2.1 The Beach–Dune Environment......Page 129
5.2.2 Depositional Rock Properties in Beach–Dune Successions......Page 131
5.2.3 Tidal-Flat and Lagoon Environments......Page 136
5.2.4 Depositional Rock Properties in Tidal Flat–Lagoon Successions......Page 138
5.2.5 The Shallow Subtidal (Neritic) Environment......Page 140
5.2.6 Depositional Rock Properties in Shallow Subtidal Successions......Page 142
5.2.7 The Slope-Break Environment......Page 143
5.2.8 Depositional Rock Properties in Slope-Break Successions......Page 144
5.2.9 The Slope Environment......Page 145
5.2.10 Depositional Rock Properties in the Slope and Slope-Toe Environments......Page 147
5.2.11 Basinal Environments......Page 148
5.2.12 Depositional Rock Properties in Basinal Environments......Page 149
5.2.13 Ideal Depositional Successions Illustrated......Page 152
5.3 Paleotopography and Depositional Facies......Page 153
5.4 Diagnosis and Mapping of Depositional Reservoirs......Page 156
Review Questions......Page 160
6.1 Diagenesis and Diagenetic Processes......Page 163
6.1.1 Definition of Diagenesis......Page 164
6.1.2 Diagenetic Processes......Page 165
6.2 Diagenetic Porosity......Page 169
6.3 Diagenetic Environments and Facies......Page 172
6.3.1 Diagenetic Facies......Page 174
6.4 Diagenetically Enhanced Porosity......Page 175
6.4.1 Enhancement by Recrystallization......Page 177
6.4.2 Enhancement by Solution Enlargement......Page 179
6.4.3 Large-Scale Dissolution-Related Porosity......Page 180
6.4.5 Recognizing Enhanced Porosity......Page 182
6.5 Porosity Reduction by Diagenesis......Page 183
6.5.2 Pore Reduction by Recrystallization......Page 184
6.5.3 Pore Reduction by Replacement......Page 185
6.5.4 Pore Reduction by Cementation......Page 186
6.5.5 Recognizing Diagenetically Reduced Porosity......Page 189
6.6 Diagnosing and Mapping Diagenetic Reservoirs......Page 190
Suggestions for Further Reading......Page 193
Review Questions......Page 194
7.1 Fractures and Fractured Reservoirs......Page 195
7.1.2 Types of Fractures......Page 196
7.1.3 Genetic Classification of Fractures......Page 197
7.1.4 Fracture Morphology......Page 200
7.1.5 Where Do Fractures Occur?......Page 203
7.2 Fracture Permeability, Porosity, and S(w)......Page 205
7.2.1 Fracture Permeability......Page 206
7.2.2 Fracture Porosity......Page 207
7.2.3 S(w) in Fractured Reservoirs......Page 208
7.3 Classification of Fractured Reservoirs......Page 209
7.4 Detecting Fractured Reservoirs......Page 210
7.4.2 Indirect Methods to Detect Fractures in the Borehole......Page 211
7.6 Identifying and Developing Fractured Reservoirs......Page 214
Review Questions......Page 217
8 SUMMARY: GEOLOGY OF CARBONATE RESERVOIRS......Page 219
8.1 Rock Properties and Diagnostic Methods......Page 220
8.1.1 Fundamental Rock Properties and Depositional Reservoirs......Page 221
8.1.2 Reservoir Morphology......Page 222
8.1.4 Tertiary Properties and Petrophysical Characteristics......Page 223
8.2 Data Requirements......Page 225
8.2.2 Field Scale Studies......Page 226
8.2.3 Quality Ranking of Flow Units......Page 227
8.3 Depositional Reservoirs......Page 228
8.3.1 Finding and Interpreting Depositional Reservoirs......Page 229
8.3.2 Selected Examples of Depositional Reservoirs......Page 232
8.3.2.1 North Haynesville Field......Page 233
8.3.2.2 Conley Field......Page 238
8.4.1 Finding and Interpreting Diagenetic Reservoirs......Page 243
8.4.2 Field Examples of Diagenetic Reservoirs......Page 245
8.4.2.1 Overton FIeld......Page 246
8.4.2.2 Happy Field......Page 250
8.5.1 Finding and Interpreting Fractured Reservoirs......Page 258
8.5.2 Field Examples of Fractured Reservoirs......Page 259
8.5.2.1 Quanah City Field......Page 260
8.5.2.2 Dickinson Field......Page 263
8.6 Conclusions......Page 268
Review Questions......Page 273
REFERENCES......Page 274
INDEX......Page 288