Overton Cotton Valley Field: Expansion, Development and

     Optimization of a Tight Sandstone Reservoir

The Overton field is located in Smith and Cherokee Counties, Texas southeast of Tyler on the western flank of the Sabine uplift in the East Texas basin.  The field produces from the Taylor interval, the lowest member of the Jurassic Cotton Valley Sand.  As is typical of most production from the Cotton Valley, these sands have very low permeability, with the distribution of rock quality controlled by a complex depositional and diagenetic history.  Discovered by American Petrofina in 1978, the field has experienced both an initial development phase and a more recent significant expansion and infill.  Field production is currently in excess of 100 MMCFD with over 250 wells drilled.

This presentation will present field data documenting the low permeability and stratigraphic nature of the reservoir.  It will also demonstrate how the integration of geologic and engineering data has resulted in optimized well locations and field extension, as well as enhanced completion practices and improved operational efficiencies.  As will be shown, this has resulted in significant additional natural gas resource development and production, as well as an efficient and comprehensive development of the field.