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Gorda Ridge pp 179-189 | Cite as

Technologies for Geophysical Exploration on the Ocean Bottom

  • John A. Hildebrand
Conference paper
  • 95 Downloads

Abstract

Several approaches have been used for ocean bottom geophysical exploration including magnetic, gravity, and seismic methods. Magnetic anomalies near the ocean bottom are measured with a nuclear precession magnetometer deployed from a deeply towed vehicle. They reveal fine-scale crustal magnetization indicating geomagnetic field reversals and zones of varying lithology. Gravity anomalies of the ocean bottom are measured with a gravimeter placed on the seafloor. The seafloor gravimeter is more precise than sea surface gravimeters owing to greater platform stability, and it has improved capability for revealing crustal density structures because of its closer proximity to crustal sources. Ocean bottom seismic methods use on-bottom seismographs or hydrophones and on-bottom shots. Use of on-bottom seismic instrumentation allows characterization of shallow inhomogeneous crustral structure. Accurate positioning is needed for fine-scale ocean bottom geophysical exploration and may be accomplished with acoustic transponders and satellite navigation.

Keywords

Magnetic Anomaly Gravity Anomaly Ocean Bottom Mooring Line Syntactic Foam 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag New York Inc. 1990

Authors and Affiliations

  • John A. Hildebrand

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