Well Logging and Formation Evaluation

This hand guide in the Gulf Drilling Guides series offers practical techniques that are valuable to petrophysicists and engineers in their day-to-day jobs. Based on the author’s many years of experience working in oil companies around the world, this guide is a comprehensive collection of techniques and rules of thumb that work.

The primary functions of the drilling or petroleum engineer are to ensure that the right operational decisions are made during the course of drilling and testing a well, from data gathering, completion and testing, and thereafter to provide the necessary parameters to enable an accurate static and dynamic model of the reservoir to be constructed. This guide supplies these, and many other, answers to their everyday problems.

There are chapters on NMR logging, core analysis, sampling, and interpretation of the data to give the engineer a full picture of the formation. There is no other single guide like this, covering all aspects of well logging and formation evaluation, completely updated with the latest techniques and applications.

· A valuable reference dedicated solely to well logging and formation evaluation. · Comprehensive coverage of the latest technologies and practices, including, troubleshooting for stuck pipe, operational decisions, and logging contracts. · Packed with money-saving and time saving strategies for the engineer working in the field.

Petroleum geologists, geophysicists, reservoir engineers and drilling engineers.

Introduction

1. Basics 1.1 Terminology 1.2 Basic Log Types 1.3 Logging Contracts 1.4 Preparing a Logging Programme 1.5 Operational Decisions 1.6 Coring 1.7 Wellsite Mud Logging 1.8 Testing/Production Issues

2. Quicklook Log Interpretation 2.1 Basic Quality Control 2.2 Identifying the Reservoir 2.3 Identifying the Fluid Type and Contracts 2.4 Calculating the Porosity 2.5 Calculating Hydrocarbon Saturation 2.6 Presenting the Results 2.7 Pressure/Sampling 2.8 Permeability Determination

3. Full Interpretation 3.1 Net Sand Definition 3.2 Porosity Calculation 3.3 Archie Saturation 3.4 Permeability

4. Saturation/Height Analysis 4.1 Core Capillary Pressure Analysis 4.2 Log-Derived Functions

5. Advanced Log Interpretation Techniques 5.1 Shaly Sand Analysis 5.2 Carbonates 5.3 Multi-Mineral/Statistical Models 5.4 NMR Logging 5.5 Fuzzy Logic 5.6 Thin Beds 5.7 Thermal Decay Neutron Interpretation 5.8 Error Analyses 5.9 Borehole Corrections

6. Integration with Seismic 6.1 Synthetic Seismograms 6.2 Fluid Replacement Modelling 6.3 Acoustic/Elastic Impedance Modelling

7. Rock Mechanics Issues

8. Value of Information

9. Equity Determinations 9.1 Basis for Equity Determination

   9.2 Procedures/Timing for Equity Determination 9.3 The Role of the Petrophysicist

10. Production Geology Issues 10.1 Understanding Geological Maps 10.2 Basic Geological Concepts

11. Reservoir Engineering Issues 11.1 Behavior of Gases 11.2 Behavior of Oil/.Wet Gas Reservoirs 11.3 Material Balance 11.4 Darcy’s Law 11.5 Well Testing

12. Homing-in Techniques 12.1 Magnetostatic Homing-In 12.2 Electromagnetic Homing-In

13. Well Deviation, Surveying, and Geosteering 13.1 Well Deviation 13.2 Surveying 13.3 Geosteering 13.4 Horizontal Wells Drilled about a Contact 13.5 Estimating the Productivity Index for Long Horizontal Wells

Appendix 1: Test Well 1 Data Sheet Appendix 2: Additional Data for Full Evaluation Appendix 3: Solutions to Exercies Appendix 4: Additional Mathematics Theory Appendix 5: Abbreviations and Acronyms Appendix 6: Useful Conversion Units and Constants Appendix 7: Contractor Tool Mnemonics Bibliography About the Author Acknowledgments Index