自己浮上式海底地震系(ERI型P-79)

概要

論文の詳細を見る
A new type of pop-up OBS (P-79) was developed. The P-79 has the following features: the newly developed release system; use of new sensors (2 Hz vertical and horizontal geophones and one hydrophone); a new gimbal for geophones; the use of glass sphere pressure case; a low wow-flatter recorder deck; and easy handling. The main causes of OBS noise might be the motor of the recorder and the Karman vortex due to bottom current. Motor noise was reduced by the use of a foam rubber insulator. The dominant noise frequency due to the Karman vortex was discussed. A 50 cm/sec bottom current may produce a 16 Hz Karman noise around the antenna of a radio transmitter with 0.6 cm in antenna diameter. The new release system utilizes an electrical corrosion of stainless-steel wire. Dual timers in separate pressure cases feed one release mechanism. Pop-up tests were successfully done at sea.
1980-03-31