Pore Pressure, Fracture Pressure and Wellbore Stability Management (GG21)

DATE		LOCATION		FEES			REGISTRATION
Nov 29-Dec 3, 2010		Vienna, Austria			Course Fee: EUR 2475 plus VAT

Instructor Tim Watts

• The origins of geopressure and the basic physics of geological environments.


• The concepts of hydrostatic, overburden and effective stresses.


• The type of data needed and its quality.


• The appropriate level of detail required for geopressure prediction and analysis.


• Management of drilling operations through the correct application of wellbore stability principles.


• Pressure Prediction


• Fracture Gradient


• Wellbore stability


• Fracture calculation and wellbore stability whilst drilling

• Planning
  – Pressure Prediction: use of seismic data and velocity analysis is introduced.
  Basin modelling principles are covered including lithology typing, compaction curves and burial history for use in wildcat exploration drilling. The use of offset data and extrapolation techniques when planning infill wells is also covered.
  – Fracture Gradient: Leak off test and mud loss interpretation, fracture gradient, pore pressure and overburden inter-relationships are used to derive operational forecasts for well planning. The effects of lithology and tectonic stress on fracture pressure is illustrated in clastic and evaporite sequences.
  – Wellbore stability: Collapse and breakout pressures will be calculated using different stress orientations and well trajectories. Strategies for static and dynamic mud weight management are discussed to ensure successful drilling campaigns can be conducted in the most challenging of subsurface conditions.
  


• Execution
  – Pore pressure detection and wellsite evaluation whilst drilling: Qualitative drilling methods using connection gas, background gas, drilling exponents and drilling speed are explained. Torque and drag, hole fill and cuttings character, will be examined and their interpretation discussed. The pitfalls of flowline and MWD temperature analysis are illustrated. Quantitative methods of pressure estimation plus direct measurement techniques will be taught, these include: wireline and logging whilst drilling measurements, drillstem tests and kick data. Indirect logging methods using porosity density and resistivity data, the selection of compaction trends, the effects of clay diagenesis, tectonic stress, unconformities and unloading are demonstrated.
  Transition zones and the drilling parameters associated with them are illustrated. You will learn how to interpret the signs of decreasing overbalance and steps to follow in case this occurs. Measuring and estimating pressures in low permeability environments is also covered. You will also see the effects of multiphase fluids and how the gradients change in different zones. You will be guided through kick detection methods and the well control procedures needed to maintain safe drilling operations.
  – Fracture calculation and wellbore stability whilst drilling: The use of lost circulation information and leak off tests to calibrate calculated fracture pressures will be taught. Indirect indicators such as differential sticking, mud chemistry, caving morphology and drillstring behaviour, will be used to give clues as to how fractured formations are reacting. This course will also teach simple and robust well bore stability management techniques covering what to do when things go wrong.