Post date: Aug 19, 2013 6:2:7 PM
USA (Next Media) - The US government will this year announce a decision on whether to allow seismic airgun testing for oil and gas deposits along an area from Delaware to Cape Canaveral, Florida.
A draft environmental study by the federal government predicts that if allowed along the Atlantic coast, seismic testing would injure 138,500 whales and dolphins and cause 13.5 million disruptions of activities such as hunting and breeding. Environmentalists say that figure relies on flawed data and is way too low.A seismic surveying ship tows a seismic airgun, which shoots extremely loud blasts of compressed air through the ocean and miles under the seabed. Echoes are detected by the hydrophone array, reaching each hydrophone at different times and thus allowing the surveyors to pinpoint the direction from which the echoes are coming and the densities of materials like gas and oil within the ocean floor.
The blasts are fired several times a minute over a period of weeks as the surveying vessel maps an area, searching for deposits of oil and gas under the ocean floor.
SOURCES: Marine Science Today, New York Times, EPA, Ocean.org
http://marinesciencetoday.com/2013/04/18/seismic-airgun-use-a-threat-to-more-than-just-marine-life/
green.blogs.nytimes.com/2012/10/11/will-seismic-blasts-upend-atlantic-marine-life/
http://www.epa.gov/esd/cmb/GeophysicsWebsite/pages/reference/methods/Marine_Geophysical_Methods/Marine_Seismic_Methods.htm
http://oceana.org/sites/default/files/Oceana_Seismic_Airgun_Testing_Infographic_PDF.pdf