Dr.  Greg Samways:  Course creator and presenter.

Logging technology is developing all the time and downhole tools are becoming more sophisticated, but there is still a need to understand the fundamentals of the basic openhole logging tools.  These fundamentals underpin the functioning of all of the more sophisticated downhole logging tools, so it is important to have a good grounding in the basics.

Take a look at the proposed course content below and let us know what would be of interest to you in the comments.

The proposed course materials would include the following modules:

STOIIP Fundamentals

• Identifying the parameters that we are most interested in, namely: N:G, porosity, saturation, permeability, recovery factor and formation volume factor
• Defining which of these can be derived from logs
• Exercise: STOIIP Calculations

Drilling and Logging Process

• Understanding the drilling process and how borehole quality can affect log responses
• Understanding the logging and sampling processes, the potential pitfalls and impact on log data quality
• Quiz: Test our knowledge

Rocks and Fluids

• Defining the fundamental properties of rocks and their control on reservoir parameters, namely: grain size, sorting, clay content
• Understanding how rocks and fluids interact and hence how the geology controls porosity, permeability, wettability, fluid saturations and capillary pressure
• Quiz: Test our knowledge

Logging Tool Theory

• Understanding what the different types of logs are measuring: electrical properties, nuclear (neutrons and gamma-rays), sound
• Sources of natural gamma-rays
• Gamma-ray spectra
• Compton scattering
• How sound travels through rocks and fluids
• How neutrons interact with the formation
• Quiz: Test our knowledge

Log Functionality

• A review of each logging tool: how they work, what they measure, their calibration and corrections.
• The tools: Caliper, Tension, Gamma-Ray, SP, Neutron, Density, Photo Electric Factor (PEF), Sonic, Resistivity / Induction
• Exercise: Familiarisation with the log data sets

Data Quality Control

• Bad hole condition
• Irregular logging speeds
• Core-to-log and log-to-log matching
• Missing data
• Exercise: Identification and correction of bad data

Lithology and Porosity Determination

• Determination of lithology from gamma-ray, spectral gamma-ray, neutron, density and PEF logs, augmented by sonic and resistivity.
• M + N plots, MID plots (tmaa vs rhomaa; Umaa vs rhomaa),
• V-shale determination
• Determination of porosity from density, neutron, sonic and various combinations of the three logs.
• Exercise: Working with carbonate and clastic logs

Fluid Saturation Determination

• Archie equation
• Introduction to shaly sand equations: e.g. Simandoux, Waxman Smits, Indonesian.
• Pickett plots
• Exercise: Fluid saturation deter5minations using the Archie equation and Pickett plots.

Sedimentological Interpretation

• Identification of lithological trends (shaliness / grain-size)
• Log facies analysis
• Borehole image analysis
• Depositional modelling
• Exercise: Working with carbonate and clastic logs

Sequence Stratigraphic Correlation

• Fundamentals of parasequences and flooding surfaces, and their identification in logs
• Parasequence stacking patterns and systems tracts, and their identification in logs
• Sequence boundaries and their identification in logs
• Correlation of flooding surfaces, systems tracts and sequence boundaries
• Exercise: Working with carbonate and clastic logs

Permeability and Flow Unit Determination

• Log indicators of permeability
• Porosity-permeability transforms
• Introduction to well tests and NMR
• Introduction to rock typing, Reservoir Quality Indexes (RQI) and Fluid Zone Indicators (FZI)
• Exercise: Working with carbonate and clastic logs

If there is anything else would like to see, or you want a different emphasis, please contact us.