Relating Fracture Network Characteristics to Shale Gas Reserve Estimation

Abstract

Abstract The Stretched Exponential production Decline Model (SEDM) provides a flexible framework for forcasting production and estimating reserves in unconventional reservoirs. In the following we use the Discrete Fracture Network (DFN) concept to interpret the SEDM results obtained previously. Our study proposes that the SEDM exponent parameter, n can be related to the scale independent characteristics of the created fracture network that in turn can be considered non-varying in a given field (or larger group of wells in the same geological settings and of similar completion type.) Our hypothesis is supported by dry gas flow simulation involving stochastic generation of DFN with various characteristics. The effect of variations in natural fracture lengths, apertures, density, and connectivity are considered along with induced hydraulic fracture dimensions. In view of our findings we present another conditioning approach to robust decline curve analysis and provide application examples for selected Barnett Shale wells.