Assessment of Probabilistic Parameters for Barnett Shale Recoverable Volumes

The Barnett shale is a renowned Resource play and one of the most developed in North America with enormous hydrocarbon potential located in the Fort Worth basin of North Central Texas. Unitl December 2010, it was the largest producing natural gas field in the United States, averaging 5.5 Bcf/d and cumulative production of 9 Tcf as at the end of 2010. However, in spite of its success, it is difficult to predict well performance and reserves with certainty largely due to geological complexity and completion variations. Thus, it is common to see wells in the same producing interval exhibiting large differences in producing rates and estimated ultimate recoveries (EUR). Peak monthly rate (PMR) or, month of highest production, usually occurs in the first three months. It has been found to be quite useful by some operators in predicting gas reserves because of its favorable correlation with EUR. In this paper, 2,932 Horizontal gas wells were sampled from the top six producing counties in