MAGNETIC-PROPERTIES OF GORRINGE RIDGE SER PENTINITES

Magnetic properties of serpentinites in the third layer of oceanic cru st are investigated. Their contribution to the anomalous magnetic fiel d is estimated. Drilled samples from Gorringe Ridge were studied. Data obtained from magnetological measurements showed that the samples hav e both high remanence magnetization (5-20 A/m) and magnetic succeptabi lity values, All samples have high Koenigsberger factor (7-17) that sh ows the ability of these rocks to have magnetization not induced by mo dern magnetic field. Spectral magnetic research showed that the only m agnetoactive phase of all the serpentinites investigated is magnetite. Multidomain grains of magnetite prevails, but pseudosingle domains of magnetite are also present in some samples. The detailed analys of ma gnetic inclination showed its chaotic variation but these variations w ere less in the parts of drillcores less affected by tectonics and hyd rothermal alteration.