Reservoir Analysis of Gas Reservoirs

A natural gas contains a variety of hydrocarbon molecules ranging from methane (CH4) to very heavy hydrocarbons, all of which are in the gaseous state at initial reservoir conditions.  Produced intermediate to heavier weight hydrocarbons liquidfy at the surface and become a major source of income.  Calculations are performed to characterize the gas-liquid relationship in order to set separation conditions and predict performance of the two phases.

Gas reservoir performance histories are governed by any repressuring assistance exerted by natural water influx that may vary from a complete absence to a case where a strong water drive dominates performance.  Ultimate recovery is greatest in the pressure depletion case due to gas compressibility effects exhausting more residual gas.

Gas compressibility is the predominant influence on production history on low to moderate gas reservoirs.  However the effects of formation and water compressibiliry must be included in studies describing overpressured gas reservoirs.

Top Learning Objectives

  • Recognize reservoir gas may be classed as dry, wet or condensate or retrograde condensate, all of which may be recognized by phase diagrams and production characteristics.
  • Understand differences between single- and two-phase z-factor.
  • Understand the contents of a laboratory fluid analysis report.
  • Interpret performance from gas and rich gas reservoir from knowledge of changes in fluid properties.
  • Recognize the utility of the material balance (p/z vs Gp plot) for the pressure depletion case in order to diagnose inter-well behavior.
  • Apply the transient p/z method to substitute transient pressure measurements for static pressures when applying the material balance equation.
  • Recognize the effects of overpressured conditions and water influx cause the (p/z vs Gp plot) to overestimate original gas in place.
  • Realize production effects on normal, overpressured and water drive gas reservoirs can be determined with a material balance calculation.
  • Apply the solution plot method to study overpressured gas reservoirs.
  • Forecast future performance from a well test or with a boundary dominated solution to the diffusivity equation for the dry and wet gas cases. Estimate performance with the Eaton – Jacoby correlation for the condensate reservoir situation.

Who Should Attend?

Reservoir engineers and professionals who work in collaboration with reservoir engineers, including well engineers, facilities engineers, process engineers, petrophysicists and geoscientists.

  • Reservoir Engineers
  • Well Engineers
  • Facilities Engineers
  • Process Engineers
  • Petrophysicists
  • Geoscientists
  • Economists
  • Planners
  • Management

Event Details

4th – 6th May 2020
Abidjan, Ivory Coast