ACTIVE SEISMICITY IN THE FIJI PLATEAU OBSERVED BY OCEAN-BOTTOM SEISMOGRAPH

Abstract

An ocean-bottom seismographic observation was performed at the central part of the Fiji Plateau in Aug. 20-29, 1973. It was found that intense micro-earthquake activity, including two swarm activities, were taking place in the neighbourhood of an ocean-bottom seismographic station located very close to the spreading center inferred by CHASE (1971). The average daily frequency of occurrence was about ll earthquakes per day at the station. The sea floor of the Fiji Plateau was unusually restless with numerous small tremors, which seem to be generated by natural earthquakes. The central part of the Fiji Plateau seems to be tectonically very active at present.