Well Screen and Optimal Time of Refracturing : A Barnett Shale Well

Abstract EN

Gas-production decline in hydraulically fractured wells in shale formations necessitates refracturing.

However, the vast number of wells in a field makes selection of the right well challenging.

Additionally, the success of a refracturing job depends on the time to refracture a shale-gas well during its production life.

In this paper we present a numerical simulation approach to development of a methodology for screening a well and to determine the optimal time of refracturing.

We implemented our methodology for a well in the Barnett Shale, where we had access to data.

The success of a refracturing job depends on reservoir characteristics and the initial induced fracture network.

Systematic sensitivity analyses were performed so that the characteristics of a shale-gas horizontal well could be specified as to the possibility of its candidacy for a successful refracturing job.

Different refracturing scenarios must be studied in detail so that the optimal design might be determined.

Given the studied trends and implications for a production indicator, the optimal time for refracturing can then be suggested for the studied well.

Numerical-simulation results indicate significant improvement (on the order of 30%) in estimated ultimate recovery (EUR) after refracturing, given presented screen criteria and optimal-time selection.