The natural gas is harnessed from the Marcellus Shale by using the technique of hydraulic fracturing.
<u>Explanation:</u>
The Marcellus Shale is a sedimentary rock about 7,000 to 12,000 feet below the Earth's surface lying beneath the states of New York, West Virginia, Ohio and Pennsylvania.
It is one of the world's richest deposits of natural gas. To extract the natural gas from this shale, the technique of hydraulic fracturing is used in which the Earth is drilled vertically and hydraulic agents like water and other chemicals are introduced into the Earth's surface at high pressure, forcing the gas to rise up to the surface.
Both vertical and horizontal Marcellus Shale wells produce marketable quantities of natural gas. The drilling process focuses first on reaching – and protecting – water-bearing zones beneath the ground. This allows for the extraction of larger quantities of natural gas from a single wellhead.
The Three Economic Sectors. According to the three-sector theory, all economic activity can be classified into one of three sectors: the primary sector, the secondary sector and thetertiary sector.
