Pore Pressure, Fracture Pressure and Well-Bore Stability
INSTRUCTOR: Selim Shaker, PhD
DISCIPLINE: Formation Evaluation
COURSE LENGTH (DAYS): 5 Days
WHO SHOULD ATTEND: Geologists, geophysicists, drilling and reservoir engineers, well log analysts, basin-model specialists, managers, and support staff involved in exploration, development and drilling.
COURSE DESCRIPTION: This is a comprehensive course using the basic models of geology, rock-mechanics and hydrodynamics to predict and appraise subsurface geopressure and, consequently, evaluate your prospect risk pre-and post-drilling.
Participants will learn how to calculate and run their own pore pressure (PP) prediction and analyses, based on a geo-scientific foundation, rather than software design.The course applies a new method of calculating pore pressure and also discusses some of the pitfalls related to specific widely used applications.
The course proceeds from the known (measured pp) to the unknown (predicted pp). It explains the development of the subsurface geopressure compartments with depth and their impact on hydrocarbon entrapments, drilling prognoses and risk assessment.
With the knowledge gained from this course you will be able to QC the measured and predicted input data. You will also learn how to use the seismic velocities and the petrophysical data from offset wells to build the prediction model for a wildcat proposed location. We will lay down the foundation of establishing the prediction variables and exponents needed for each individual basin. Moreover, the course examines in depth the calibration process of the prediction model during and post drilling. Mud weight, casing programs and anticipated drilling challenges will be discussed.
Supra salt, sub-salt models, fault seals, Strat-geopressure fairways, AVG, and drilling challenges are some of the main topics of this course. Moreover, the distribution of geological basins world wide and their impact on geopressure profiles are discussed in case history forms.
STUDENTS ARE REQUIRED THE PROVIDE THEIR OWN LAPTOP WITH MS EXCEL FOR THIS COURSE.
- Understand the causes, concepts and graphic representations of the subsurface geopressured and hydrodynamic systems.
- Calculate pressure transgression and regression from measured wire-line and log data.
- Collection and data mining of petrophysical measurement needed for pore and fracture pressure (FP) prediction.
- Establish the drilling tolerance window and safety restrictions without compromising the bore-hole stability.
- Comprehend that prediction models are subject to the geological setting and do not apply equally worldwide
- New approach to causes, models and definitions
- Geopressure vs. Hydrodynamics
- Pore pressure plots (PSI and PPG MWE), including some of their pitfalls
- PP-FP direct and pertinent measurements
- Transgression, regression, P decay, centroid, and hydrocarbon effect
- Models and methods used for PP prediction
- Data needed for PP prediction:
- Overburden vs. PS especially in Salt Basins
- Defining Top of Geopressure
- Normal Compaction Trend (NCT) delineation and pitfalls
- Assigning a model for PP-FP prediction
- Emphasis on the Effective Stress Model and Eaton’s relationship
- PP predictions calibration methods
- Technique used for PP and FP prediction
- Pre-drilling: Building the geological blocks
- Seismic velocity-Qualification for PP predictions
- Prediction model from seismic and offset wells
- Limitations and pitfalls
- While drilling: Calibration using direct and pertinent data
- Model inversion for the purpose fine adjustment
- Post-drilling: Compartmentalization, risk assessment and appraisal.
- Analysis and applications for Lead and Prospect evaluation
- Compartmentalization, seal effectiveness and retention capacity
- Transgression and regression
- Geopressure compartmentalization vs. hydrocarbon entrapment
- Strat-Geopressure Fairways analysis
- AVG (Amplitude vs. Geopressure) responses to subsurface geopressure profile
- Supra-sub salt stress models and their application for PP-FP prediction
- Build 2-D and 3-D geopressure models
- Faults sealing capacity in relation to type and angel
- Reserve and reservoir management
- Drilling casing, and mud programs
- Anticipated drilling challenges due to compartmentalization
- Challenges in deep water and HTHP environments
- Appraisal of the un-drilled offset structural segments on the prospect.
Case histories and their implications:
- Gulf of Mexico/Trinidad
- Continental North America
- Mediterranean Basin and North Sea
- Australia and Far East
Exercises, interpretations and analyses are conducted using case histories from the shelf and deep water in analog and digital formats.