Ocean Bottom Seismology

	Ocean Bottom Seismometer deployment

Our Ocean Bottom Seismology (OBS) Group operates a component of the National Science Foundation's OBS Instrument Pool, in cooperation with Woods Hole and the Scripps Institution of Oceanography. The OBS Lab supplies the national and international scientific community with unique broadband ocean bottom seismometers capable of very long deployments at sea.  These complex instruments must be able to drop to the seafloor, record earthquakes for a year and then return to the surface on command.  The recorded data is used to study structures and processes deep within the Earth’s crust and mantle.  The oceanic mantle is the key to understanding the driving forces of plate tectonics including convective processes, the fate of subducting slabs, Earth's hotspots (of which Hawaii and Iceland are the best examples), and the supply of magma to form the oceanic crust beneath ridge crests. We also study the oceanic crust using tomographic methods and man made sources (airguns and explosives). Tectonic and hydrothermal processes produce earthquakes detected by OBSs and we have even tracked animals within pods of migrating whales using whale song recorded at the seafloor. Other recent work includes mapping magnetic fields to probe temperatures within ridge crest hydrothermal systems and seafloor deformation under wave loading to study magma beneath ridge crests. A recent OBS design swims and can home to an icebreaker ship from the Arctic seafloor.