Magnetic fabrics

Abstract

Since Graham [1954; 1967] demonstrated in the 1950s and 1960s that magnetic anisotropy was a quick and non‐destructive way of measuring rock fabric, magnetic fabric measurements have become increasingly prevalent in the study of earth and environmental processes (see Table 1 for definitions of magnetic terms). The accomplishments of U.S. workers over the past 4 years show that the U.S. community continues to contribute to the growth and development of the field. In addition to the more traditional anisotropy of magnetic susceptibility (AMS) measurements work is branching out to include anisotropy of remanence studies, particularly anisotropy of anhysteretic remanence (AAR) [McCabe et al, 1985] and anisotropy of isothermal remanence (AIR), since these parameters can be tied directly to the remanence‐carrying grains in a rock and hence have relevance to the effects of magnetic fabric on natural remanent magnetization (NRM). Along with this shift is the realization, as a result of combining nonmagnetic observations (e.g.. scanning electron microscopy (SEM), finite strain measurements) with rock magnetic measurements (e.g.. hysteresis parameters), that magnetic mineral composition (paramagnetic and ferromagnetic) has an important control on magnetic anisotropy.