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Marine Geophysical Researches

, Volume 19, Issue 1, pp 81–96 | Cite as

Application of the Single-Bubble Airgun Technique for OBS-Data Acquisition Across the Jan Mayen Ridge, North Atlantic

  • Rolf Mjelde
  • Jan Petter Fjellanger
  • Per Digranes
  • Shuichi Kodaira
  • Hideki Shimamura
  • Hajime Shiobara
Article

Abstract

A 140 km long wide-angle seismic profile has been acquired by use of 6 Ocean Bottom Seismographs across the Jan Mayen Ridge, North Atlantic. The profile was acquired twice; once with a traditionally tuned standard source and secondly with a somewhat smaller source tuned on the first bubble pulse. Analysis of the frequency content of the data reveals that the single-bubble source within the 10-15 Hz frequency range generates a signal with a level about 5 db above that of the standard source. These differences can partly be related to differences in airgun depth. The higher output level for these frequencies enables the single-bubble source to resolve intra-crustal structures with a higher degree of certainty, when compared to the data acquired by use of the standard source array. The standard source seems to generate slightly more energy for frequencies around 6 Hz, probably due to the use of a large 1200 in/sup3 gun in this array. These low frequencies a re of importance for mapping of lower crustal and upper mantle structures, and it is recommended that this is taken into account when seismic sources for mapping of deep crustal and upper mantle structures are designed.

Seismic sources wide-angle seismics Jan Mayen Ridge 

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Copyright information

© Kluwer Academic Publishers 1997

Authors and Affiliations

  • Rolf Mjelde
    • 1
  • Jan Petter Fjellanger
    • 1
  • Per Digranes
    • 1
  • Shuichi Kodaira
    • 1
  • Hideki Shimamura
    • 2
  • Hajime Shiobara
    • 2
  1. 1.Institute of Solid Earth PhysicsUniv. of BergenBergenNorway
  2. 2.Laboratory for Ocean Bottom SeismologyHokkaido UniversitySapporoJapan

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