To offset the need for fuel imports, to decrease greenhouse gas emissions, and to increase U.S. energy independence, geothermal energy has emerged as an important part of the U.S. energy portfolio.

This well-illustrated study, published in Geosphere this week, presents a new and inexpensive method using Geographic information system (GIS) and National Geothermal Data System data to evaluate a region for geothermal energy exploration.

Authors Anna Crowell and Will Gosnold gathered and analyzed free-access GIS data for trends that could help geoscientists assess whether a sedimentary basin could be economically utilized for geothermal power production.

In their article, they identify several counties in the states of Colorado, Illinois, Michigan, and North Dakota where geothermal energy could be used for different energy production scenarios.

In particular, they find that the Denver-Julesberg Basin (which spans Wyoming, Nebraska, and Colorado, and has a surface area of approx. 155,000 square kilometers) has the highest capacity for large-scale, economically feasible geothermal power production.

They write that, "assuming an adequate, sustainable water supply," high-population areas west of Denver, near the depocenter of the basin and the Golden fault along the Front Range of the Rocky Mountains, are of greatest interest because costly infrastructure is already in place.

Anna Crowell and Will Gosnold, University of North Dakota, Harold Hamm School of Geology and Geological Engineering, Grand Forks, North Dakota 58202, USA. Research paper