Fossil Fuels Coal, Lignite, And Peat

ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

Authors: Brandon C. Nuttall
 
Abstract: Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO 2 is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO 2. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library are being sampled to collect CO 2 adsorption isotherms. Sidewall core samples have been acquired to investigate CO 2 displacement of methane. An elemental capture spectroscopy log has been acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 4.62 percent. CO 2 adsorption capacities at 400 psi range from a low of 19 scf/ton in less organic-rich zones to more than 86 scf/ton in the Lower Huron Member of the shale. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO 2 in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO 2, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO 2 storage and enhanced natural gas production.
Publication Date: 01 Aug 2004
DOE Contract number: FC26-02NT41442
Resource Type: Technical Report
Resource Relation: Other Information: PBD: 1 Aug 2004
Research Organizations: University of Kentucky (US)
Sponsoring Organizations: (US)
Country of Publication: United States
Language: English
Keywords relating to this report:
ADSORPTION ISOTHERMS
BLACK SHALES
CARBON DIOXIDE
GEOLOGIC SURVEYS
KENTUCKY
KEROGEN
METHANE
MINERALOGY
NATURAL GAS
PRODUCTION
SHALES
SPECTROSCOPY
VITRINITE

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