Using Production History to Identify Acid Stimulation Candidates in the Spraberry Trend

Abstract

There are currently over 10,000 wells producing in the Spraberry field of West Texas. A substantial problem in the maturing field is scale buildup on perforations created by poor reservoir water quality. Spraberry operators matrix acidize wells to remove this buildup and increase production. However, operators lack a proactive method to determine acid stimulation candidates. Currently, wells are not stimulated until scale buildup causes flow to cease entirely. Through the analysis of 32 acidized wells in the Spraberry Driver Unit, this paper defines a stimulation screening method that can proactively increase production in the field. The new production criteria specify that strong stimulation candidates are wells that have produced over 17 BOPD in their history and subsequently have shown sharp production decline rates. Stimulating a well that exhibits these criteria increases the oil production rate by an average of 94%. If only 1% of the 10,000 wells in the Spraberry were acidized, an additional 1.5 MMBbl of oil and $85 million in gross revenue could be recovered.