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Magnetic Characteristics of TA19-1 and TA19-2 Seamounts in the Lau Basin, the South Western Pacific

남서태평양 라우분지 TA19-1 해산과 TA19-2 해산의 지자기 특성 연구

  • Kim, Chang Hwan (Dokdo Research Center, East Sea Research Institute, Korea Institute Of Ocean Science & Technology)
  • 김창환 (한국해양과학기술원 동해연구소 독도전문연구센터)
  • Received : 2014.04.07
  • Accepted : 2014.05.23
  • Published : 2014.08.28

Abstract

We conducted the geophysical survey of possible hydrothermal vent sites at 2009, in the Lau Basin, the south western Pacific and analyzed the magnetic characteristics of TA19-1 and TA19-2 seamounts. TA19-1 is a cone-shaped seamount with a caldera summit. TA19-2 seamount is bigger and shows more complicated topography than TA19-1 seamount. TA19-2 has a large caldera, a summit in the west side of the caldera and several crests. Simple dipole anomalies with a high over the north and a low over the south occur in TA19-1 seamount. High magnetic anomalies are located in the northern flank and the summit of TA19-2 seamount and low anomalies around the summit and the caldera. The results of bathymetry and magnetic data suggest that TA19-2 seamount might have more complicated magmatic process than TA19-1. Low magnetization zones are located over the summit, the calderas and the caldera rims. The magnetization lows indicate that submarine hydrothermal vents, along faults and fracture zones, could have caused an alteration of magnetic minerals. The magnetization highs over the summit and the calderas might have been related with later magmatisms like volcanic sills, intrusions.

Keywords

hydrothermal vent;seamount;magnetic characteristic;caldera;magnetization

Acknowledgement

Supported by : 해양수산부, 한국해양과학기술원

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