Geological Research at the IGS
Resource assessment and production testing for coal-bed methane development in the Illinois Basin
||Oct 1, 2003
||Sep 30, 2005
Gibson, Knox, Posey, Sullivan, Vigo
||There has been a surge of national interest in coal-bed methane (CBM) in recent years because of increasing gas prices, increased demand for natural gas, environmental concerns, and the realization that previously overlooked coal basins may have significant CBM reserves. Production of CBM may be an effective way to use this vast energy resource to serve the nearby Illinois-Indiana primary market in an environmentally sound manner.
||The goal of this project is to obtain fundamental baseline information on methane for Illinois Basin coals and associated organic-rich shales. This study will provide valuable data to stimulate development of gas from areas believed to have the best potential for economically extractable CBM in the Illinois Basin.
||Three coreholes were drilled in southwestern Indiana in Posey, Gibson, and Knox Counties. Desorption analyses, geochemical tests, and petrographic analyses were performed on all recovered coals.
||1) A geologic framework to assess thickness and structural patterns of coals and black shales. These data are useful for determining the amount of coal and shale available for producing gas, and areas that may have increased permeability.
2) Methane content information for Illinois Basin coals and black shales. These data are critical for assessing the CBM resource in place.
3) Methane adsorption information for Illinois Basin coals. These values are important for determining the gas reservoir capacity of each coal.
4) Petrographic, geochemical, and isotopic data that will help quantify gas potential of Illinois basin coals, and determine the origin of the gas.
5) Tailored well-completion and production-design information that is essential for industry in order to effectively exploit this new gas resource throughout the basin.
||Coal-bed methane benefits economic development as well as environmental protection in several ways. Methane is the cleanest-burning fossil fuel, having the lowest carbon dioxide CO2 emissions, and essentially zero emissions of sulfur dioxide and nitrogen oxides. Methane also produces the least CO2 of any fossil fuel when burned. Methane produces about 1.4 pounds of CO2 per million Btus generated, whereas coal emits about 2.2 pounds of CO2 per million Btus. In addition, recovering methane in coal prior to mining can significantly reduce methane emissions from coal mining, and improve underground mine safety conditions as well.