Deep-tow magnetic survey of Fonualei Rift and Spreading Center(FRSC) at 16&#12331 35

Abstract

Fonualei Rift and Spreading Center(FRSC) are located in northeastern part of Lau basin which is the active back-arc basin. Deep-tow magnetic surveys are carried out in FRSC. In deep-tow magnetic survey, to compensate for influence of uneven distance between bathymetry and sensor height, magnetic anomaly is continued upward to a level plane. We calculate crustal magnetization by using inversion method, and try to find the hydrothermal vent and understand the structure of ocean floor crust. The result of deep-tow magnetic survey at FRSC showed that Central Anomaly magnetization High(CAMH) recorded the max value of 4.5 A/m which is associated with active ridge. The direction of SSW-NNE of CAMH corresponds with the direction of the principal spreading ridge in Lau basin. The low crustal magnetization of about 0 A/m is supposed to correlate with submarine hydrothermal vent. distance between bathymetry and sensor height, magnetic anomaly is continued upward to a level plane. We calculate crustal magnetization by using inversion method, and try to find the hydrothermal vent and understand the structure of ocean floor crust. The result of deep-tow magnetic survey at FRSC showed that Central Anomaly magnetization High(CAMH) recorded the max value of 4.5 A/m which is associated with active ridge. The direction of SSW-NNE of CAMH corresponds with the direction of the principal spreading ridge in Lau basin. The low crustal magnetization of about 0 A/m is supposed to correlate with submarine hydrothermal vent.