Beneath Appalachia, from West Virginia to New York State, is the Marcellus shale, a vast source of natural gas that could help position West Virginia and neighboring states for a clean energy future.

The Marcellus shale covers an area of 54,000 square miles, and it's thought to contain at least 50 trillion cubic feet of recoverable natural gas worth an estimated $1 trillion. Typically, wells in the Marcellus shale are dug straight down to depths of about 6,000 feet or more before making a right angle to drill horizontally into the shale. Companies use a technique called fracturing in which water pressure is used to create openings in the shale to allow the gas to flow into the horizontal well.

The Marcellus, along with other shale formations around the country, is coming under increased attention now because of the need for new energy supplies to keep our nation's economy running while importing less fuel from abroad.

That complex challenge is going to require the use of all energy sources -- clean coal, nuclear power, oil and natural gas, and renewable energy -- and ongoing improvements in energy efficiency. With domestic energy sources such as shale gas, we will become less dependent on imported oil and imported liquefied natural gas.

How much shale gas can be economically recovered in the United States is still very unclear. Certainly there is no shortage of it. According to recent estimates, there could be as much as 842 trillion cubic feet of natural gas in U.S. shales, enough to supply about 40 years worth of natural gas at today's consumption rate.

To be sure, West Virginia and the U.S. economy could benefit from increased gas production, which now accounts for much of the fuel used in industry and is the second largest source of fuel for electricity generation, next to coal. A desire for a cleaner fuel for electricity is one reason why demand for generation-related natural gas rose 54 percent between 1997 and 2006. This feature and the desire for a fuel produced domestically will assure a continued increase in the demand for natural gas production in the United States.

As for opening up natural gas resources for production, we still have a long way to go. If not for a ban on drilling that is still in place, substantial amounts of natural gas could be recovered from offshore areas in the Atlantic, Pacific and eastern Gulf of Mexico that are still off-limits to exploration and development.

With further research, we could solve the few remaining problems for economic production of shale gas. Here in the United States we are still stuck with an energy supply policy that dates back to the 1980s. We need a policy that makes sense for the world we live in today and puts us on an effective course for the future.

The United States needs to greatly reduce the amount of imported oil. To achieve this, we need more energy conservation, more wind, solar and nuclear energy and more bio-fuels. But even as we work to increase all of these, we also need more domestically produced natural gas. The failure to diversify our energy policy will lead to further consumer pain and a continued dismantling of key portions of our economy.

The economy of West Virginia can benefit by the production of Marcellus shale natural gas. West Virginia is fortunate that the state will continue to be a major contributor to the "fuels of the future" and the good jobs associated with energy production.

Donald W. Lyons is a professor of engineering at West Virginia University.

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