The Haynesville Shale of East Texas and North Louisiana was viewed as one of the most prolific shale-gas resources when it first emerged around 2010. The crash of natural gas prices in 2012 and a surge of Appalachian gas production quickly shifted activity and interest away from the Haynesville. In 2015, despite depressed commodity prices, rig activity in the Haynesville returned as operators began to drill more cost-effective wells. Recent results have shown significant improvements in both the historical core of the play and previously uneconomic areas. This study analyzes geologic, production and completion data to characterize the Haynesville to identify key drivers making this play successful, and it also compares geologic parameters from the core into expanding areas of the play.
The Upper Jurassic Haynesville Shale is an organic- and carbonate-rich mudrock deposited in a restricted basin, with paleo structures and topography strongly influencing lithology trends across the play. The Haynesville Shale ranges from 100- to 300-feet thick and is characterized by overpressuring, 8% to 12% porosity and depths of 10,000 to 14,000 feet. The Haynesville Shale currently accounts for approximately 4.5 Bcf/d of dry gas production, with initial peak calendar-day rates from recent wells averaging 15 MMcf/d. These new wells are forecast to recover about 10.5 Bcf.
Over the past few years, well completion designs have shifted towards increased proppant intensity, with some operators testing as high as 5,000 lbs/ft of proppant. The change improved well results and areas of the play that were once considered uneconomic now look very promising, expanding the economic extents of the play. The Haynesville Shale benefits from an abundance of resource, ample midstream capacity and proximity to Gulf Coast storage and export hubs, making this play increasingly attractive to operators.
This study analyzes digital well logs and production and completion data from horizontal wells to understand how geologic characteristics and well performance vary between the historical core and more recently tested and previously uneconomic areas of the Haynesville play. Tying geologic data to historical and current well results can help better characterize unconventional plays, understand key parameters that make the play successful and increase opportunity as economic limits of the play expand.
AAPG Datapages/Search and Discovery Article #90323 ©2018 AAPG Annual Convention and Exhibition, Salt Lake City, Utah, May 20-23, 2018