Biogenic magnetite as a paleomagnetic recorder of the ferromanganese crust in the West Pacific

Abstract

Various magnetic measurements were carried out to diagnose magnetic mineralogy of the ferromanganese crust obtained in the Magellan Seamounts, the West Pacific (~20°N). Thermal demagnetization revealed a Curie temperature of ~560oC, corresponding to (titano)magnetite. Component analysis of isothermal remanent magnetization identified a presence of two types of magnetite. Measurements of first order reverse curve showed a dominance of non-interacting single-domain magnetite, which is one of the intrinsic feature of biogenic magnetite.ponding to (titano)magnetite. Component analysis of isothermal remanent magnetization identified a presence of two types of magnetite. Measurements of first order reverse curve showed a dominance of non-interacting single-domain magnetite, which is one of the intrinsic feature of biogenic magnetite.