Often regarded as examples of oceanic crust. However, because they are now tectonically emplaced on land, they are atypical and might not represent n normal oceanic crust. Ophiolites are probably samples of young oceanic crust produced in back-arc basins, or fore-arc basins, associated with subduction zones (Fowler, pp.405).
Oman ophiolite harzburgite upper mantle both from: http://www.bris.ac.uk/Depts/Geol/vft/oman.html
pp. 339 of Stein, 2003 modified after McClousky et al., 2000
Why does the Ocean Depth with lithospheric age deepens with distance from the spreading ridges? Recall
Depth for Ocean Age for Lithosphere If a body cools, what happens to its density?
Ocean Bottom Seismograph http://www.geopro.com/obs.html The OBS is cased in a glass sphere which can be deployed up to water depths of 6700m, recording seismic signals directly on the seafloor with a gimbal mounted 3C-geophone and a deep sea hydrophone.
The basic principle of WARRP is utilizing the amplitude burst when P-wave energy is totally reflected beyond the critical angle of incidence. To record at wide angles large offsets are required, much larger than conventional seismic arrays can provide.
OBS application with a vertical streamer http://www.geopro.com