Kansas Geological Survey Open-file Report 2003-31

Reconstruct Oil Production History Advanced Decline Curve Analyses

• Missing oil production between 1983 to 1988 estimated for Becker #1 - completed oil history.
• Production history for Becker #4 completed between 1983 to 1988 by subtraction Becker #1 production from Becker Lease.
• Reconstructed Becker #4 history also falls on a decline curve.

 

• Oil production histories reconstructed for Wharton #1 & #2.
• Oil production for Wharton #3 during 1985-89 estimated by subtracting production from Wharton #1 & #2 from lease production.
• Reconstructed production history for Wharton #3 falls on a decline curve and indicates intermittent stimulations.

Inferences from Decline Curve Analyses

• Oil production histories were completed using initial production (IP) rates and barrel test data recorded since 1989.
• Reconstructed oil production data from wells in a lease when added together closely approximated recorded lease production.
• Available production data, for most of the productive life of each well, could be modeled by a decline curve. This means that bottom hole producing pressures (Pwfs) at the wells remained mostly unchanged.
• Recorded production data at some of the wells indicated that wells underwent intermittent stimulations.
• A very short transient decline is visible when the recorded production data is plotted on Fetkovich’sType Curve. This is indicative of low effective permeabilities existing in the reservoir.

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