Shales not yet a big factor in New Mexico gas

Feb. 9, 2012
New Mexico remains an important gas producing state, but shale gas exploration and production have been minimal, says an article by the New Mexico Bureau of Geology and Mineral Resources at New Mexico Tech in Socorro.

New Mexico remains an important gas producing state, but shale gas exploration and production have been minimal, says an article by the New Mexico Bureau of Geology and Mineral Resources at New Mexico Tech in Socorro.

Three vertical exploratory wells recently tested the Pierre and Niobrara shales that have characteristics favorable for gas production in the Raton basin.

The Upper Cretaceous Lewis shale in the San Juan basin has been recompleted in vertical wells that have depleted in deeper reservoirs but has not become a major producer. And the Devonian Percha shale in southwestern New Mexico has “intriguing possibilities,” wrote Ron Broadhead and L. Greer Price.

The Devonian Woodford shale, Mississippian Barnett shale, Pennsylvanian Morrow and Atoka shales, and the Permian Wolfcamp shales have possibilities in the Permian basin but have not been adequately evaluated.

Meanwhile, New Mexico produced 1.3 tcf of gas in 2010, 22% below the peak of 1.68 tcf in 2001 largely as a result of depletion of San Juan basin Fruitland coal reservoirs and also with depletion of conventional San Juan and Permian basin reservoirs.

One-third of the state’s gas is produced from tight sandstones in 30,000 San Juan basin wells, where development once considered unconventional has become routine.

Coalbed methane has fallen 33% since peaking at 612 bcf/year in 1999. Raton and Vermejo formations in the Raton basin cover a fraction of the area of the Fruitland coals but produced 26 bcf/year in 2006-10 without fracing.

About half of the wells drilled in New Mexico are horizontal and nearly every well is hydraulically fractured, Broadhead and Price wrote.

Natural gas that could be produced from frontier basins such as the Tucumcari basin in east-central New Mexico is being discussed as a backup for energy sources such as wind and solar that by themselves can provide only intermittent power.