Rock magnetic properties and titanomagnetite oxydation state of ODP Hole 109-648B (Table 1)

The titanomagnetite oxidation state of "zero age" ocean floor basalts was investigated. For this purpose the oxidation parameter, z, of Hole 648B basalts was determined by SEM observation of "shrinkage cracks" in individual titanomagnetite grains and by Curie temperature measurements. A mean z-value of 0.1 has been deduced for the Hole 648B basalts. Assuming a linear relationship between titanomagnetite low-temperature oxidation state and age of the oceanic basalt, an age of 0.7 m.y. is deduced for Hole 648B.