Source: Popular Science
Author: Sara Kiley Watson
Every step of the drilling process can cause harm to the delicate ocean environment.
In early January, U.S. Secretary of the Interior Ryan Zinke announced that more than 90 percent of the outer continental shelf in federal offshore areas is now available for offshore drilling exploration and development. In the official release, Zinke noted that the plan for this new exploration would strike a balance between protecting the coasts and achieving “energy dominance” in America. But marine scientists say that scale is really tipped. Opening up more areas to drilling, they say, means far more disruption for marine ecosystems and an even greater increased risk for oil spills.
Offshore drilling is way more than sucking up oil through pipes.
Mohammed Gabr, professor of civil engineering at North Carolina State University, says that offshore drilling requires three steps: investigating the site, boring exploratory wells, and laying the pipe, and each one can affect the ecosystems that surround the area.
To find potential oil deposits, engineers can use seismic techniques like generating sound waves, Gabr says. The waves bounce along the sea bed and reflect and identify the kind of stone underneath. If sound waves indicate the possibility of oil beneath the ocean bottom, the oil company then builds an exploratory well. This initial drilling is not necessarily to look for oil Gabr says, but to understand the structure and composition of the soil sediments. He likens the process to sticking a straw into a piece of cake: when removed, the straw will contain every layer of that cake.
Once they understand the soil’s makeup, Gabr says the company starts the search for oil. With the hole in place, workers pump mud in to prevent it from caving in. Then they place a casing in to house the pipe that will pull the oil out. As the hole gets closer to hitting oil, workers use cement to secure the casing. This hole exists under pressure, which must be controlled to make sure that the oil doesn’t come rushing up too quickly, he says. An oil spill can happen at any point along the oil production process, including drilling and the set up that goes along with it.
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