Magnetic Anisotropy, Sedimentary Rocks and Strain Alteration
The relationship between anisotropy of magnetic susceptibility (AMS) fabrics (the shape and orientation of the AMS ellipsoid) and rock fabrics has been studied for over 40 years. Many studies have employed magnetic fabrics as an independent data set to compare with remanent magnetization directional data. Magnetic fabrics can also be very sensitive indicators of low‐intensity strain, though deformation exceeding 10% to 20% often modifies or destroys the fabric to the point of making a functional interpretation impossible. This is in part due to diagenetic processes; for example, reduction, pressure solution, recrystallization, fluid migrations, and growth of new mineral constituents occurring with greater degrees of strain. Thus, AMS techniques are most often successful in investigating tectonic strains on weakly deformed sedimentary rocks.
While AMS fabrics are most often easily interpreted in sedimentary rocks, the method is nonetheless complicated by the great range of primary...
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