Geopressure and Prospect’s Risk Assessment

Selim Shaker

This course examines integrated petrophysical properties to the subsurface geological, rock mechanics, and hydrodynamic models (subsurface Pore and Fracture Pressures) and their applications for E&P.

A viable prospect is contingent on the presence of a reservoir that can contain and deliver hydrocarbon, competent seal, and drillable well trajectory. These amalgamated aspects are chiefly a consequence of the subsurface geopressure vertical and lateral partitions. Geophysics plays an essential role in appraising the prospect’s risk before, during, and post drilling based on the subsurface geopressure compartmentalization. Moreover, successful drilling relies on accurate prediction of pore-fracture (PPP-FP) pressure within the drilling tolerance window and their safety limitations.


12 Hours

Intended Audience

Geophysicists, geologists, petrophysicists, drilling and reservoir engineers, geopressure modelers, hydro-geologists, rock-mechanic scientists, geosciences technicians, and almost all technical personnel in the oil patch. This course is greatly helpful for explorationists and technical personnel that are keen on prospect appraisal in-house and farm-in/out prospects.


Fundamental understanding of geology and geophysics and educational background of physics and mathematics is very useful.

Course Outline

  1. Fundamentals
    • Explain the integrated process of prospect generation.
    • Demonstrate the subsurface geopressure zones and their models.
    • Discuss the measured pore (MPP) / fracture (FP) pressure tools, charts, and plots.
    • Explain the different prediction methods (PPP) with a special focus on the effective stress models and their algorithms.
  2. Geophysical Data for Pore Pressure Prediction (Before Drilling)
    • Select and QC seismic velocity.
    • Design the PPP transformation model based on stacking, RMS, Dix velocities, and other petrophysical properties e.g. ΔT, R, ρ, VSP of offset wells.
    • Distinguish velocity trends in normally, hydrodynamically, and geopressured systems.
    • Calculate the pre-drilling mud weight and casing seat depths in bare dry hole vs. potential producer.
  3. During and post drilling assessment
    • Calibrate the pre-drilling prediction seismic model with the real time data (LWD’s).
    • Incorporate the offset well log data and measured PP (RFT’s, MDT’s).
    • Identify challenging intervals along the well bore trajectory.
    • Appraise the success of finding hydrocarbon and lessons learned in case of failure.
  4. Geopressure Applications
    • Diagnose possible seal failure and reservoir breach on seismic lines (Sequence Stratigraphy) during prospect generation.
    • Appraise potential reserves in four vs. faulted three-way closures.
    • Assess drilling challenges in Deepwater.
    • Recognize and appraise the Supra and Subsalt impact on the geopressure and trapping mechanism.
    • Distinguish the PSDM blind zone due to shale – sand velocity crossing over and possible impact on AVO assessment.
    • Appraise the potential of the under-explored and bypass pay zones in the untested structural segments in the prospect and play concept.

Learning outcomes

  • Recognize the significance of subsurface pressure partitions to hydrocarbon generation, migration, and entrapments.
  • Distinguish the geological causes of measured (sand) vs. predicted (shale)pore pressure disparity.
  • Assess drilling challenges in Deepwater and Salt basins.
  • Recognize the salt displacement and emplacement geomechanics impact on seals and trapping mechanisms integrity.

Instructor Biography

Selim Simon Shaker