The Marcellus Shale formation in eastern United States contains large amounts of natural gas. To drill and obtain this gas, large amounts of water "to drill and hydraulically fracture the rock." This shale stretches from New York to West Virginia, gaining thickness as it goes from west to east. The thickest part is made up of sandstone, siltstone, and shale, while the thin western part is finer-grained, organic-rich black shale. Since this shale has been being heated and compressed since the Devonian Age, the organic matter has formed hydrocarbons, and within the pore spaces, mineral grains are absorbed within the shale. A technique called "hydrofrac" is used to get larger quantities of the natural from the rock. This is when water under high pressure is used to form fractures in the rock, which causes pathways for the gas to move to the well. The US Dept. of Energy funded the Eastern Gas Shales Project in the 70s and 80s, which focused on advancing the commercial aspect of Devonian Shale gas. However, this yielded uneven results, so they concluded "stimulation alone was generally insufficient to achieve commercial shale gas production." Later on in the 1980s, the Institute of Gas Technology discovered that the "gas-in-place" value of the Marcellus Shale was significantly higher than originally expected. In 2008, two professors found that about 50 TCF of recoverable natural gas could be taken from the shale. Later in 2008, it was raised to 363 TCF. The United States uses only about 23 TCF of natural gas a year, so if consumption stays as it is now, that can last us about 15 years. The sudden interest in the Marcellus Shale is due to the rising cost of wellheads and the new technology of drilling, which makes it easier. One of the downsides to this idea is the amount of water needed for it to work. Some of the concerns are using water, but not impacting the surrounding towns' water supply, destroying roads with the heavy equipment, and finding proper ways to get rid of "potentially contaminated" fluids. In all, the potential drilling of the Marcellus Shale is still under debate. While natural gas is the cleanest burning energy source, the impact on the people around the shale just might be too much.
wellhead- general term used to describe the pressure containing component at the surface of an oil well that provides the interface for drilling and production equipment.
1. The single most important problem that supports the opposition to drilling is the water issue. A large amount of it is required if we are to get resources from this shale. One of the concerns is where this water will come from and not contaminating local water supply. Also, another concern is what they will do with it once it's contaminated. An idea for this came from Texas, where they leave it out to evaporate and then dispose of the solid. However, that probably won't work in the humid climate the Marcellus Shale is in.
2. I read through all of the sources, and they all seemed to come from reliable places. The data was all collected over a span of several months, so that gave the author adequate time to find good sources. Also, the article was edited and it was published, so the sources should be reliable.
3. Figure 7 is slightly odd because gel like that is not mentioned in the text at all, so it seems (at least to me) a little random. Also, it's a bit odd as well because you wouldn't think goopy gel would carry proppants well.
My questions
1. Why don't we try harder to find a different solution to the need for natural resources? Or, better yet, why don't we try to wean off them?
2. What would happen to the water supply around the drill sites if they did happen to get contaminated? What sort of consequences would it bring?
3. If they did use the evaporation of the contaminated fluids, where would they discard of the sediment? Will it cause any issues?
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