Research is aimed at determining the feasibility of drilling directly into Wilcox coal seams in central Louisiana for coalbed methane production.
Central Louisiana coals lie between the Monroe uplift on the northeast, the Darbonne platform on the NNW, and the Sabine platform on the west. The LaSalle arch separates the major coal basin into two smaller basins in the general vicinity of 12n-2w and 13n-2w, Winn Parish.
Workers at Basin Research Institute, Louisiana State University, Baton Rouge, have mapped an area of about 6,730 sq miles centered around LaSalle Parish. They have produced a top Wilcox structure map and a Wilcox isopach map showing only the Wilcox gas fields.
The lignites are estimated to be sub-bituminous and are not known to outcrop. Sidewall descriptions reveal a brittle, black, shiny, fractured coal. Depth to the coal beds is generally less than 3,000 ft. Some areas have 20-30 coal beds with individual seam thicknesses of as much as 40 ft.
The work has determined that gas in the general area of Caldwell, Winn, and LaSalle parishes is probably biogenically sourced by bacteria that have "fed" on the Wilcox lignites.
One well is known to have perforated a coal interval. Vertically drilled prior to the modern U.S. coalbed meth- ane era, it flowed water and methane for a few months, said John B. Echols, assistant professor-research.
Further work probably depends on funding from operators or the state.
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