Paleomagnetism of a Core from Osaka Bay

Abstract

A giant core sample 20 cm in diameter of shallow water sediment from Osaka Bay, Japan, was paleomagnetically analyzed. Remanent magnetization of the sediment exhibits somewhat large directional dispersion in each horizon comparing to that of lacustrine deposit. The magnetization possesses a continuous record of the geomagnetic field direction for the past 6240 years consistent with that from another core data of a previous work. Two notable characteristic features of the magnetization, small amplitude in directional changes and unstability to alternating field demagnetization, are explained as results of post depositional realignments of magnetic grains. © 1985, Society of Geomagnetism and Earth, Planetary and Space Sciences. All rights reserved.