Cahaba Basin
Encyclopedia
The Cahaba Basin is a geologic area of central Alabama
developed for coal
and coalbed methane
(CBM) production. Centered in eastern Bibb and southwestern Shelby Counties, the basin is significantly smaller in area and production than the larger Black Warrior Basin
in Tuscaloosa and western Jefferson Counties to the northwest. The coalbed methane is produced from the Gurnee Field of the Pottsville Coal Interval. Coalbed gas production has been continuous since at least 1990 and annual gas production has increased from 344,875 Mcf in 1990 to 3,154, 554 Mcf through October 2007.
from the neighboring Black Warrior Basin. Within the Cahaba Basin, the Pennsylvanian Age coal beds have an average bed thickness of 50 feet. The developed formations are known as the Gurnee Field of the Pottsville Formation.
Alabama
Alabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland...
developed for coal
Coal
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...
and coalbed methane
Coalbed methane
Coalbed methane or Coal Bed Methane, coalbed gas or coal mine methane is a form of natural gas extracted from coal beds. In recent decades it has become an important source of energy in United States, Canada, and other countries...
(CBM) production. Centered in eastern Bibb and southwestern Shelby Counties, the basin is significantly smaller in area and production than the larger Black Warrior Basin
Black Warrior Basin
The Black Warrior Basin is a geologic sedimentary basin of western Alabama and northern Mississippi in the United States. It is named for the Black Warrior River and is developed for coal and coalbed methane production, as well as for conventional oil and natural gas production...
in Tuscaloosa and western Jefferson Counties to the northwest. The coalbed methane is produced from the Gurnee Field of the Pottsville Coal Interval. Coalbed gas production has been continuous since at least 1990 and annual gas production has increased from 344,875 Mcf in 1990 to 3,154, 554 Mcf through October 2007.
Geology
The Cahaba Basin is located across an anticlineAnticline
In structural geology, an anticline is a fold that is convex up and has its oldest beds at its core. The term is not to be confused with antiform, which is a purely descriptive term for any fold that is convex up. Therefore if age relationships In structural geology, an anticline is a fold that is...
from the neighboring Black Warrior Basin. Within the Cahaba Basin, the Pennsylvanian Age coal beds have an average bed thickness of 50 feet. The developed formations are known as the Gurnee Field of the Pottsville Formation.
Development
The coal resources of the Cahaba Basin have been developed for over a century and contributed to the Birmingham area's rise as an iron and steel production center. Numerous small coal mines continue to operate in the basin. Several CBM developers operate within the Cahaba Basin with GeoMet, Inc. and CDX Gas being two of the largest. The field has been developed for CBM since the 1980s. GeoMet, Inc. and CDX both operate pipelines which join the SONAT Bessemer Calera Pipeline and Enbridge Pipeline respectively. GeoMet, Inc. operates a discharge water pipeline to the Black Warrior River.External links
- Geological Survey of Alabama; Alabama State Oil and Gas Board
- http://www.coalbed.com/ Coalbed Methane Association of Alabama; non-profit trade association
- CDX Gas – a significant Cahaba Basin CBM developer
- GeoMet, Inc. - a significant Cahaba Basin CBM developer