Well Log Interpretation - WLI

May 29, 2014

The most universal, comprehensive and concise descriptive documents on oil and gas wells are logs. They impact the work of almost every oilfield group from geologists to roustabouts to bankers. Familiarity with the purposes and optimum applications of well logs is therefore essential for people forging their careers in the oil business. The instructor uses a novel approach to help participants develop a good grounding in understanding and applying well logging techniques. General principles of physics are developed to explain the functioning of modern logging tools. Wherever possible, the physics of logging measurements is related to everyday tools and appliances. Participants develop an appreciation for the constraints and limitations of operating in the borehole environment. A number of actual log examples are related to basic principles in the description of reservoir properties such as porosity, mineralogy, formation factor, saturation, and hydrocarbon type, for essentially clean reservoirs. Cross-plotting and reconnaissance techniques (the eyes of the part-time log interpreter), quickly and efficiently discriminate between water, oil, and gas. Error minimization techniques, applicable only to computerized log analysis, produce optimal results. Participants gain realistic experience by working in teams on a comprehensive log interpretation exercise.

Petrophysicists, geologists, geophysicists, engineers, technicians, or anyone interested in a solid understanding of the principles of borehole geophysics.

You will Learn:

Participants will learn how to:

  • Identify reservoirs
  • Determine mineralogy, porosity and saturation in various lithogies
  • Recognize the importance of electrical properties of earth materials
  • Highlight oil mobility
  • Interpret pressure profiles
  • Develop optimum tools and logging programs
  • Apply quickbook methods of formation evaluation

Course Content:

  • Logging objectives
  • Invasion profile
  • Challenge of borehole geophysics
  • Passive electrical properties of earth materials
  • Resistivity measuring tools, normal, induction, laterolog
  • Reservoir/non-reservoir discrimination
  • Matrix-sensitivity logs, GR, SGR, Pe
  • Depth measurements and control
  • Borehole calipers
  • Porosity-mineralogy logs, density, neutron, sonic
  • Porosity determination in clean formations
  • Formation resistivity factor
  • Conductivity of shales
  • Porosity log crossplots and mineralogy identification
  • Partially saturated rock properties and Archie Equation
  • Linear movable oil plot
  • Reconnaissance techniques, Rwa, FR/FP, logarithmic scaler
  • Logarithmic MOP
  • Porosity-resistivity crossplots
  • Permeability relationships
  • Nuclear magnetic resonance
  • Use of pressure measurements
  • Computerized log evaluation
  • Sidewall coring
  • Recommended logging programs