An Analysis of the Historical (Re)-Stimulation Results for 62 Dolomite Wells in the Texas Panhandle

Abstract

Modeling a well`s production response from a fracture stimulation design is a science. There are several commercial computer software packages that link fracture propagation models to reservoir simulation models. Data requirements to use these software packages include descriptions of fracture fluid behavior, rock mechanical properties, vertical stress distributions, and reservoir characteristics. There are many cm histories that illustrate the adequacy of these models to predict economic outcomes. However, these models are not able to predict the production response resulting from the fracture (re)-stimulation where no input data is available. This particular situation exists for wells drilled prior to 1950. Oil and gas development in the Texas Hugoton and West Panhandle Fields began in the 1920`s. Many gas wells in these fields were originally stimulated with nitroglycerin or gelled naphtha and proppant. Strip logs recorded by drillers and geologists provide most of the sub-surface information available in this area. A decision to initiate a stimulation and/or restimulation program for old wells in these fields would necessarily have to come initially from intuitive judgment. Results from the initial program can be useful to help predict the outcome of future (re)-stimulation programs. Presented in this paper are the results obtained from the (re)-stimulationmore » of 62 gas wells in the Texas Hugoton and West Panhandle Fields. These results will provide a basis to model the uncertainty of (re)-stimulating similar old wells. The model relates the economic uncertainty to incremental production rate increases, incremental reserves and chance estimates when considering (re)-stimulation in the Texas Hugoton and West Panhandle Fields.« less