Print this pageAnalyzing Hydraulically Fractured Gas Well Performance in the Greater Green River Basin of Wyoming*
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Abstract
Hydraulic fracture stimulation often
dictates the economic outcome of 
wells
completed in low permeability gas
reservoirs. Evaluating well performance - the rate and pressure behavior of a
well over its productive life - provides the opportunity to discover the key
elements driving stimulation and completion effectiveness in any particular
environment. This presentation demonstrates the integrated use of reservoir
engineering, petrophysical and geologic analysis to evaluate well performance,
identify flow regimes and distinguish between reservoir and completion induced
behavior. Tools used include well log analysis (for pay identification and
petrophysical calculations), the reciprocal productivity semi-log method (to
normalize the inevitable variations in flow rate when evaluating the
post-linear, infinite acting radial flow period), fractured well type-curve
analysis, pressure buildup analysis and numerical simulation. The main emphasis
is an expanded discussion outlining the fundamentals of production data
analysis. Case studies from the Greater Green River Basin of Wyoming of single
wells and entire fields draining low permeability gas reservoirs are used to
demonstrate this methodology, and significant reservoir, completion, and
production factors affecting well performance are identified as an outcome. The
impact of critical completion and production factors will be revealed and
discussed. These problems and factors include wellbore liquid loading (in
reducing or eliminating the effective hydraulic fracture length), treatment
sizing, treatment isolation strategies and sequencing of multi-pay completions,
treatment flowback strategy, use of velocity/ tubing strings and selection of
landing depths, and shutting in a producing well. Remedies are suggested for
stimulation and completion induced problems.
Almond
Formation, Lookout Wash Field
, Washakie Basin
Lodgepole 20-29, underperforming welll, Moxa Arch / La Barge Platform