Bending and Collapse: Magnetic Recording Fidelity of Magnetofossils From Micromagnetic Simulation

Magnetosome chains produced by magnetotactic bacteria are important paleoenvironmental and paleomagnetic recorders. It has been shown that magnetic properties of magnetosome closely related to their morphology chain structures; however, the in situ structures sediments (magnetofossils) not known. subject various deformations after cell dissolution therefore unlikely be fully intact, obscuring original signals. Here, we use finite element micromagnetic simulations quantify changes signals response deformation, particular, as a function variable degrees bending collapse. Our results indicate bending/collapse leads significant coercivity reduction domain state transition chain. Therefore, hysteresis parameters can used assess degree magnetofossil-rich sediments. Calculations contributions post-depositional remanent magnetization (pDRM) magnetofossils pDRM remains both faithful pre-bending/collapse natural magnetization, remanence some structurally deformed magnetofossil assemblages thermally stable over billion-year timescales, suggesting even strongly ancient geological materials retain records thus have potentials for tracing geomagnetic field variations microbial activities on early Earth.