New methods for separation of inverse and normal AMS fabric components
|Year of publication
|MU Faculty or unit
|Generally, the inverse magnetic fabric describes inverse relationship between magnetic fabric and petrofabric, where magnetic lineation is parallel to the pole of petrofabric foliation. On the other hand, the term “normal magnetic fabric” is used when the magnetic fabric matches with the petrofabric. However, naturally occurring samples can contain both components. In this case one of the fabrics may overprint the other one, or a composite magnetic fabric can occur instead. That usually makes any interpretation very difficult. Here, we present new methods for separation of inverse and normal magnetic fabric components. First method is based on simple chemical destruction of one component in the sample. Delicate treatment with the samples allows to preserve remaining body of the sample that can be remeasured again without one component. In our case, iron carbonates responsible for inverse magnetic fabric component were dissolved in hydrochloric acid. The second method is based on the mathematical separation of one component fabric from the original composite fabric. The one component fabric can be reached by above described chemical destruction or using another method such as measurements of anisotropy of anhysteretic remanent magnetization / anisotropy of anhysteretic susceptibility (McCabe et al., 1985, Jackson, 1991) or heating treatment (De Wall & Warr, 2004). Both our new methods for separation of AMS fabrics will be presented together with software we created.