Well recovery, drainage area, and future drill-well inventory: Empirical study of the Barnett shale gas play

The work is focused on one of the oldest and largest developed shale-gas plays-the Barnett shale. The primary objective is to bring more clarity and granularity to the Barnett resource estimation. The second task is to develop a resource-estimation methodology that one can use to evaluate other shale-gas plays in an attempt to determine their potential for development. We compile a comprehensive database, including production histories of more than 16,000 drilled wells and calibrated density log porosity and net-pay-zone-thickness maps. The data are used to estimate (1) the remaining technically recoverable free-gas resource, (2) individual-well recoveries, (3) areas drained by the existing wells, and (4) the future drill-well inventory. On the basis of the geographical distribution of individual-well estimated ultimate recoveries, we divide the Barnett acreage into 10 tiers. We describe the future drill-well inventory for each tier. In addition, to assess the potential contribution of refracturing to the future Barnett production, we develop a statistical procedure to identify wells that are likely to be refractured and then analyze their performances.