Well Logging and Formation Evaluation


  • Toby Darling, Toby Darling Limited

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.
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Petroleum geologists, geophysicists, reservoir engineers and drilling engineers.


Book information

  • Published: February 2005
  • ISBN: 978-0-7506-7883-4


"A concise guide to both well logging as well as other important topics in evaluating formations … I recommend the book as an addition to most any petrophysicist's working library." - William D. Moore, Hereford, Arizona in the AAPG Bulletin, December 2005

Table of Contents

Introduction1. Basics1.1 Terminology 1.2 Basic Log Types1.3 Logging Contracts1.4 Preparing a Logging Programme1.5 Operational Decisions1.6 Coring1.7 Wellsite Mud Logging1.8 Testing/Production Issues 2. Quicklook Log Interpretation2.1 Basic Quality Control 2.2 Identifying the Reservoir2.3 Identifying the Fluid Type and Contracts2.4 Calculating the Porosity2.5 Calculating Hydrocarbon Saturation2.6 Presenting the Results2.7 Pressure/Sampling2.8 Permeability Determination3. Full Interpretation3.1 Net Sand Definition3.2 Porosity Calculation3.3 Archie Saturation3.4 Permeability4. Saturation/Height Analysis4.1 Core Capillary Pressure Analysis4.2 Log-Derived Functions5. Advanced Log Interpretation Techniques5.1 Shaly Sand Analysis5.2 Carbonates5.3 Multi-Mineral/Statistical Models5.4 NMR Logging5.5 Fuzzy Logic5.6 Thin Beds5.7 Thermal Decay Neutron Interpretation5.8 Error Analyses5.9 Borehole Corrections6. Integration with Seismic6.1 Synthetic Seismograms6.2 Fluid Replacement Modelling6.3 Acoustic/Elastic Impedance Modelling7. Rock Mechanics Issues8. Value of Information9. 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 Issues10.1 Understanding Geological Maps10.2 Basic Geological Concepts11. Reservoir Engineering Issues11.1 Behavior of Gases11.2 Behavior of Oil/.Wet Gas Reservoirs11.3 Material Balance11.4 Darcy’s Law11.5 Well Testing12. Homing-in Techniques12.1 Magnetostatic Homing-In12.2 Electromagnetic Homing-In 13. Well Deviation, Surveying, and Geosteering13.1 Well Deviation13.2 Surveying13.3 Geosteering13.4 Horizontal Wells Drilled about a Contact13.5 Estimating the Productivity Index for Long Horizontal WellsAppendix 1: Test Well 1 Data SheetAppendix 2: Additional Data for Full EvaluationAppendix 3: Solutions to ExerciesAppendix 4: Additional Mathematics TheoryAppendix 5: Abbreviations and AcronymsAppendix 6: Useful Conversion Units and ConstantsAppendix 7: Contractor Tool MnemonicsBibliographyAbout the AuthorAcknowledgmentsIndex