NMFS Issues Three Seismic IHAs to L-DEO
On July 16, 2012, the U.S. National Marine Fisheries Service published Federal Register notice that it has issued three Incidental Harassment Authorizations to the Lamont-Doherty Earth Observatory, a part of Columbia University, to take marine mammals, by Level B harassment, incidental to conducting three consecutive marine geophysical surveys in the northeast Pacific Ocean, June through July, 2012. These IHAs are issued pursuant to NMFS authority under the Marine Mammal Protection Act.
In support of these IHAs, the U.S. National Science Foundation has prepared an Environmental Assessment and Finding of No Significant Impact Determination Pursuant to the National Environmental Policy Act, 42 U.S.C. 4321 et seq. and Executive Order 12114, Marine Seismic Surveys in the northeastern Pacific Ocean, 2012. This Environmental Assessment incorporates an Environmental Assessment of Marine Geophysical Surveys by the R/V Marcus G. Langseth in the Northeastern Pacific Ocean, JuneJuly 2012, prepared by LGL Limited Environmental Research Associates, on behalf of NSF. NMFS also issued a Biological Opinion under section 7 of the Endangered Species Act to evaluate the effects of the survey and IHAs on marine species listed as threatened or endangered. The Biological Opinion will be available online at: http://www.nmfs.noaa.gov/pr/consultations/opinions.htm.
L-DEO will use one source vessel, the R/V Marcus G. Langseth, a seismic airgun array, a single hydrophone streamer, and ocean bottom seismometers to conduct the seismic surveys. The surveys will provide data necessary to:
Characterize the evolution and state of hydration of the Juan de Fuca plate at the Cascadia subduction zone;
Provide information on the buried structures in the region; and
Assess the location, physical state, fluid budget, and methane systems of the Juan de Fuca plate boundary and overlying crust.
The results of the three studies will provide background information for generating improved earthquake hazards analyses and a better understanding of the processes that control megathrust
earthquakes, which are produced by a sudden slip along the boundary between a subducting and an overriding plate.
Click here to read NMFS Federal Register notice