Mark Puumala HBSc thesis abstract

Thesis Title: 
Experimental Investigation of Magnetic Fabrics in Simulated Geological Materials

Anisotropy of magnetic susceptibility in rocks has been previously demonstrated to be related to strain.  The magnitude ellipsoid of magnetic susceptibility in a rock generally has its principal axes coincident with the axes of the ellipsoid finite strain.

In this study, the development of magnetic fabric was observed in an easily deformable medium (plasticene) which may simulate the development of magnetic fabric rock.

Magnetite, chlorite, and quartz sand were added to the plasticene in a number of experiments to alter the susceptibility of the plasticene "matrix".

The principal axes of the susceptibility ellipsoid were related to experimental deformation conditions.  These experiments showed that anisotropy of magnetic susceptibility increases with strain and that the principal axes of susceptibility are approximately coincident with the principal axes of strain.

The susceptibility of the maximum and minimum axes for approximately homogeneously deformed plasticene were shown to increase linearly from a point of isotropic fabric with increasing magnetite content (Henry's relationship).

Addition of quartz sand to plasticene resulted in a decrease in susceptibility which may be a linear function of sand content.