AAPG Studies in Geology No. 50, (Section Title: The Ferron Coalbed Methane Play) Chapter 19: Coalbed Gas in the Ferron Sandstone Member of the Mancos Shale: A Major Upper Cretaceous Play in Central Utah, by Scott L. Montgomery, David E. Tabet, and Charles E. Barker, Pages 500 - 528
from:
AAPG Studies in Geology No. 50: Regional to Wellbore Analog for Fluvial-Deltaic Reservoir Modeling: The Ferron Sandstone of Utah, Edited by Thomas C. Chidsey, Jr., Roy D. Adams, and Thomas H. Morris
Copyright © 2004 by The American Association of Petroleum Geologists and the Society of Exploration Geophysicists. All rights reserved.

The Ferron Coalbed Methane Play

Chapter 19:
Coalbed Gas in the Ferron Sandstone Member of the Mancos Shale:
A Major Upper Cretaceous Play in Central Utah

Scott L. Montgomery¹, David E. Tabet², and Charles E. Barker^3
1Petroleum Consultant, Seattle, Washington
²Utah Geological Survey, Salt Lake City, Utah
³U.S. Geological Survey, Denver, Colorado

South Main Street, Huntington, Utah, circa 1900. Photograph used by permission, Utah State Historical Society, all rights reserved.

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ABSTRACT

Drilling for coalbed gas in the Upper Cretaceous Ferron Sandstone of central Utah during the 1990s has resulted in one of the most successful plays of this kind. Development through the year 2003 has resulted in three fields, as well as a potential fairway 6-10 mi (10-16 km) wide and 20-60 mi (32-96 km) long, corresponding to shallow coal occurrence at depths from 1100-3500 ft (330-1060 m) in the Ferron, a sequence of interbedded fluvial-deltaic sandstone, shale, and coal in the lower part of the Cretaceous Mancos Shale. The major reservoirs in this interval consist of thin to moderately thick (3-30 ft [1-10 m]) coalbeds of relatively low rank (high-volatile B bituminous) and variable gas content, ranging from 100 scf/ton (3.0 cm³/g) or less in the south to as high as 500 scf/ton (15.6 cm³/g) in the north. Other lithologies also contain gas and contribute a minor portion of the produced gas. Productive wells have averaged over 500 mcf/day and, after several years of production, continue to typically show increases in gas production. In the major productive area, Drunkards Wash unit, the first 33 producers averaged 974 mcf and 85 bbl of water per day after five years of continuous production. Estimated ultimate recoverable reserves for individual wells in this unit average about 1.9 bcf, with one standard deviation about that mean of plus or minus 1.5 bcf.