Well logs are detailed record of the geologic formations by a borehole. These are comprehensive and important data gathered in any phase of a well’s history to identify petrophysical properties which in turn defines the economic value of a reservoir. The techniques in analysis and interpretation of well logs are therefore essential in identification of oil recovery.

In the E&P business, integrated petroleum engineering studies and field development plans are management tools which are used to maximize economic recovery of hydrocarbons. Petrophysical engineers fulfill a key role in analyzing and interpreting subsurface reservoir data, which form the basis for reservoir models. E&P technical staff and team leaders involved in integrated studies require more than general skills in petrophysical and interpretation techniques to produce quality input to development plans.

The trainer will provide understanding of practical and new techniques and tools in well logging with the support of case studies. At the end of the course, participants will be able to quantitatively identify the reservoir quality, measure the storage capacity of the reservoir through integrating the reservoir and petrophysical data and to improve oil recovery.

DAY 1

Introduction to Petrophysics

The Rock Physical properties and the petrophysical parameters. These petrophysical parameters include:

• Porosity, 
• Permeability 
• Volume of shale, 
• Fluid saturations.

Well Logging Tools include:

• Open-Hole Logging Tools. 
• Logging While Drilling (LWD) Tools. 
• Cased-Hole Logging Tools.

Open-Hole Logging Tools   

• Definition, measurements, application, equations of the following tools:
• Lithology Tools: Gamma Ray, Spectral Gamma Ray, Spontaneous Potential Tools
• Porosity Tools: Sonic, Density, Neutron Tools
• Resistivity Tools: Dual-Latero, Dual-Induction, Micro-Spherical Resistivity Tools

Case study: The effect of shale volume 
Exercise: Determination of petrophysical parameters 

 

DAY 2

Logging Operations and Quality Control

• Logging Tools Operations
• Log Quality Control

Introduction to Logging While Drilling (LWD)

• Lithology Tools
• Resistivity Tools
• Porosity Tools

Quick Look Well Log Interpretation: 

• Lithology interpretation
• Porosity calculations
• Rw determination and Petrophysical parameters (a,m,n)
• Vshale estimation
• Fluid Saturation 
• Permeability
• Permeability & Porosity relationship

Formation Evaluation

• Porosity Types
• Total Porosity and Lithology Interpretation 
• Rw determination methods and Petrophysical parameters (a,m,n)
• Effective Porosity and Vsh Determination
• Fluid Saturation, Archie’s Relationship and other Saturation Equations.
• Permeability.

Case study: Calculation of the petrophysical parameters 
Exercise: Calculation the fluid saturation

DAY 3

Other Open-Hole Logging Tools: 

• Definition, measurements, application:
• Electromagnetic Propagation Time Tool and Dipmeter.

Case study: EPT log example 
Exercise:  Calculate Variable ‘m’ from EPT equation

Recent and Advanced Tools:

• Geological Tools: FMS, FMI
• Magnetic Resonance Tools: NMR, CMR

Case study: FMI log example 
Exercise: Differentiate between these different structural elements. 
Case study: CMR log 
Exercise: Define free hydrocarbon and away from the bound fluid

Open and Cased-Hole Logging Tools: 

Pressure Tools

• Principles and interpretation of the other open hole logging tools which can be run in cased holes:
  • Repeat Formation Tester (RFT) tool 
  • Modular Formation Dynamics Tester (MDT) 

For:

• Determine static reservoir pressure
• Locate formation fluid contacts
• Verify reservoir isolation.
• Indicate reservoir depletion.
• Calculate reservoir permeability.

Case study: RFT / MDT log example
Exercise: Differentiate between the different gradients of different types of fluids

Open and Cased-Hole Logging Tools: 

• Principles and interpretation of cased hole logging tools which can be run in open holes:
  • Thermal Decay Time tool (TDT)
  • Reservoir Saturation tool (RST) 

For:

• Monitoring Fluid Contacts
• Reservoir monitoring.

Case study: TDT / RST log example
Exercise: TDT log example using open-hole logging data

DAY 4

Cased-Hole Logging Tools

• Definitions, Measurements, Applications, Equations
  • Cement Bond (CBL) & Variable Density (VDL) log:
    • Principles and interpretation of Cement Bond (CBL) & variable
    • Density (VDL) tool for zone-to-zone isolation and reservoir monitoring
    • Applications to field development.
• Cement Bond (CBL) & Variable Density (VDL) log details:
  • Principle of Operation
  • Basic Sonic Theory
  • Cement Bond Log (CBL)
  • Variable Density Log (VDL)
  • Quantitative Interpretation of CBL and Qualitative Interpretation of  VDL using: CBL – VDL Log Example
• For:
  • Evaluate zone-to-zone isolation:
  • Cement coverage of casing for corrosion protection, mechanical strength
  • Identify cement top
  • Evaluate cement repair jobs
• The Rig Cementing and Remedial cementing works using CBL /VDL results related to Petrophysics and Reservoir Monitoring.
• Well completion related to perforation intervals according CBL / VDL results.

Case study: CBL / VDL log example
Exercise: Perforation intervals and top of cement by using the CBL /VDL log example. 

• Production logging (PLT) log:
  • Principles and interpretation of production logging tools (PLT):
  • Applications to field development.
• Production logging (PLT) log include:
  • Fullbore – Spinner, or continuous, or packer Flowmeters.
  • Gradiomanometer.
  • Manometer.  
  • Thermometer 
  • Caliper & Radioactive Tracer
• For:
  • Evaluation of completion efficiency.
  • Detailed information on which perforation are plugged and which are producing or accepting.
  • Monitoring of reservoir production.                 
  • Evaluation of reservoir production or injection efficiency.
  • Essential guidance for Remedial and Workover, jobs 

Case study : PLT log example 
Exercise: Determine the perforation

DAY 5

Advanced Formation Evaluation

• Reservoir Petrophysical Model Evaluation:
• Reservoir Characteristics:
• Modern Approaches and Techniques in Petrophysics
• Multi-Well Bases Study Using:
  • Multi-Well Data-Base
  • Key Well Study
  • Data Normalization
  • Variable Petrophysical Parameter values
  • Standardization of Petrophysical Parameter
• Lithology Determination
  • Lithology Model
  • Lithological Parameters
• Petrophysical Parameters Determination
  • Archie’s Parameters
  • Most Problematic Parameters
  • Old Methods (Constant Value)
  • New Methods (Variable Values)
• Introduction to Computer Processed Interpretation using:
• Practical Training Exercises for:
  • Hydrocarbon Quality
  • Fluid Contacts (GOC-GWC-OWC-ODT-WUT-FWL)
  • Reservoir Summations
• Applications to field Development 

Cases Studies Including

• Carbonate reservoir (Limestone)
• Clastics reservoir (Sandstone)
• Gas Sandstone reservoir 

Cases studies: Including:  Carbonate and Clastics Reservoirs 

Case study – 1: Reservoir Petrophysical Modeling

Case study – 2: Unconventional Reservoir Example

Case study – 3: Unconventional Reservoir Examples 

Case study – 4: Rock Typing
Examples with different contacts (OWC, GWC , and Gas / Oil / Water contacts)  

Exercises
Practical Training Examples: 
Raw Log Data for Quick Look Interpretation and Formation Evaluation.