How Large Is The Marcellus Shale? Unconventional Gas Reserves

The Marcellus Shale is a layer of rock that lies under Pennsylvania, West Virginia, Ohio, New York, Maryland and other Northeastern United States. The Marcellus shale can be found under part of Quebec Canada as well, where companies such as Questerre Energy are drilling new wells. The size of the Marcellus shale, in terms of the portion which contains natural gas and petroleum liquids, is approximately 95,000 square miles. Compared to the productive portion of the Barnett shale, which is approximately 5,000 square miles, this is an incredibly large reserve of natural gas and liquids. The Marcellus formation lies under more than sixty percent of the state of Pennsylvania alone.

The economic value of the Marcellus Shale has been overlooked until now simply because the technology to recover the gas contained in shale rock formations did not previously exist. Now oil and gas exploration companies such as Chesapeake Energy, Devon Energy, Petrohawk Energy and others can now use a process called directional drilling to drill across the bed of rock sideways and allow more gas to seep out into the well.

Some geologists and petroleum engineers believe that the massive Marcellus shale formation may hold as much as 500 to 700 trillion cubic feet of natural gas.

Shale is a dense but relatively soft rock that was formed millions of years ago when the Northeastern United States and Canada were covered by shallow seas. These seas were full of marine life, such as plankton, fish, etc, all of which eventually died and settled into mud at the bottom of the seafloor. Over millions of years this sediment was compacted and the dense rock known as shale was formed. Over time the shale was buried deeper underground and covered with more layers of dense rock, and oil and gas were formed from the breakdown of organic matter and trapped inside the rock.

How Much Natural Gas Is In The Marcellus Shale

This amount of natural gas contained in the Marcellus Shale could supply the entire east coast for the next fifty years or more according to some geologists.

Proponents of domestic sources of energy, such as oil man T. Boone Pickens, believe that we can use natural gas from the Marcellus shale, as well as that from other shale formations, such as as the Barnett Shale, to power our vehicles. Cars and trucks can easily be converted to run on natural gas using storage tanks fitted in the trunk or underneath the vehicles. Also, natural gas can be transformed into diesel at a refinery using "gas to liquids technology".

The Marcellus shale holds the possibility of reducing foreign oil imports and helping boost the economy of one of the the United States by providing jobs and tax revenue for governments.

In the case of a similar shale formation, the Barnett near Fort Worth Texas the impact has been as great as five new Boeing Jet factories, in terms of impact on the local economy.

There are obstacles to be overcome. Shale gas is recovered from the Marcellus formation using a process known as "hydraulic fracturing", or a "frac job". In a frac job, thousands of gallons of water and chemicals, are pumped underground at extremely high pressure. In normal circumstances this water only does it's intended job, which is to fracture the shale and allow gas to be recovered. Chesapeake Energy has pledged to avoid the most toxic chemicals in the frac jobs that they are doing in the Marcellus shale. They list the ingredients as shown in this article at EnergyIndustryPhotos.com

When proper safeguards are not followed there is the chance that the frac fluid can contaminate zones that contain groundwater. So far there are no reported incidents of this happening, despite the fact that the process has been used in thousands of wells since the 1950's. This has caused some environmental groups and landowners to question whether the practice should be allowed. Since the Gulf Of Mexico disaster we should see even tighter regulations and safeguards on the practice of hydraulic fracturing. There have been documented cases of groundwater contamination from a process known as "water injection", used to flush oil from old reservoirs or gas from coal beds, contaminates ground water. This process is unrelated to hydraulic fracturing but has caused a lot of confusion from groups who think the two processes are the same thing. New York state currently has a ban on hydraulic fracturing. With every activity comes some level of risk. If you weigh the risks of domestic drilling against acquiring oil and gas from conflict plagued regions around the world, it becomes clear that we should not ignore this incredible resource under our feet.

Once the environmental hurdles are overcome there is no doubt that most of the area of the Marcellus shale will be developed and this rich source of domestic energy will help us kick the foreign oil habit. For more about the Marcellus shale formation see Marcellus Facts

Note: A new oil discovery has been made under the Marcellus shale in a similar rock formation called the Utica Shale. Chesapeake Energy recently reported it may be the largest domestic discovery of oil made in over 50 years. The Utica shale may hold as much as 25 billion barrels of oil. Presently there is a frenzy of exploration activity in Eastern Ohio, where the Utica shale is believed to hold great quantities of oil. See the hub below for more information.