Laboratory alteration of titanomagnetites in submarine pillow lavas
Submarine basalts have been heated in water in the laboratory to study the changes of magnetic properties with oxidation of the titanomagnetite. Before heating, the titanomagnetites were cation deficient with z ~ 0.1. With prolonged heating the degree of cation deficiency, as determined from the Curie temperature, increased Further heating in an attempt to produce titanomagnetites with z > 0.6 caused phase-splitting. This phase-splitting was sometimes accompanied by a self-reversal of magnetization. From the results of the experimental alterations we are able to predict the decrease of magnetization with distance from a spreading ridge.