Experimental Investigations of Viscous Remanent Magnetization Using a Continuous Measurement System

Abstract

This study showed that with a simple circuit modification this new continuous measurement system of viscous remanent magnetization (VRM) can be made more flexible as a far as the magnitude of the applied field and VRM response are concerned. It also became evident that samples ought to be allowed to decay in a zero field for 24 hrs. prior to experimentation. The IRDP rocks showed two types of VRM behaviour i) a linear logt relationship ii) a linear logt relationship but with a distinct increase in slope at about 2 x 104 secs. Why this occurs is not clear, it may be due to experimental conditions or more likely due to some physical property of the rock. The Bermudan rocks in general showed no relationship with time, but this is probably due to their past experimental history. The determination of susceptibility using this apparatus is relatively quick and produced precise results. However care must be taken with rocks that acquire a viscous moment rapidly i.e. large viscosity coefficients.

Keywords: Pages: 65 Supervisors: James Hall