The Oblique Seismic Experiment in oceanic crust-equipment and technique

In an Oblique Seismic Experiment (OSE), shots which have been generated at the surface from small (<1 km) to large (>10 km) ranges, are received in an oceanic crustal borehole. The objective is to study the shallow structure of the oceanic crust in the vicinity of the hole. A three component borehole geophone with a discrete variable gain preamplifier was developed for the experiment by modifying a commercially available tool. The first successful OSE in oceanic crust was carried out on DSDP Leg 52 in March, 1977. The experiment demonstrated the feasibility of instrumenting oceanic crustal boreholes.