Selection of Basalts for Paleointensity Studies

Abstract

The selection of basalt samples for the determination of paleointensity , proposed by based mainly on the low-temperature susceptibility variation, may not be adequate for the purpose. Besides the Type 2 basalts in their classification, the magnetic mineral Fe2 .9Ti0.1O4 (TM10), which occurs commonly in basalts, also shows an increase in the susceptibility at low temperatures . It is shown that these two could be distinguished from each other by using an extra criterion like coercive force or Curie temperature and the TM 10 bearing basalts , not quite suitable for paleointensity measurements, could be separated.