Types of Seismic SurveysData was collected in two modes, one-ship mode and two-ship mode.
In one-ship mode seismic reflection data are recorded by a 2.5 km long streamer on the shooting ship, and refraction data is collected by seismometers located onshore and offshore. When a recording streamer is being towed, the ship can not manuever to avoid boat traffic. Large ships can not pass close astern of the research vessel without damaging the submerged streamer. The Coast Guard assists by notifying ships if they are likely to interfere with operations.
In two-ship mode reflection data and refraction data are collected on the second ship. Additional refraction data are recorded by seismometers. |
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U.S. Department of the Interior U.S. Geological Survey Western Coastal & Marine Geology
URL: http://walrus.wr.usgs.gov/ships/surveys.html
for more information, contact Mike Fisher
maintained by Laura Zink Torresan
last modified 14 August 2006 (lzt)