A Feasibility Study of Microbialites as Paleomagnetic Recorders

Microbialites–layered, organosedimentary deposits–exist in the geologic record and extend back deep time, including all estimated times of inner core nucleation. Microbialites may preserve magnetic field variations at high-resolution based on their growth rates. Previous studies have shown that microbialites can a stable magnetization. However, timing origin microbialite magnetization were not well determined, no study has attempted to evaluate whether actively growing geomagnetic field. Here, we present centimeter-scale property within structure modern from Great Salt Lake (GSL), United States, Laguna Bacalar, Mexico, Pleistocene GSL, Cambrian Mongolia. All samples directions close expected value. The dominant carrier coercivity 35–50 mT unblocking temperatures are consistent with magnetite. A small proportion additional high minerals such as hematite also present, but do appear appreciably contribute natural remanent (NRM). Magnetization is broadly along layers, directional correlate internal slope layers. These observations suggest documented NRM be primarily detrital acquisition sediment deposition.