ROCK MAGNETIC PROPERTIES OF THE L5 ORDINARY CHONDRITE DAULE

Abstract

This thesis presents the results from rock magnetic experiments on the Daule L5 ordinary chondrite meteorite. The utilized rock magnetic techniques include thermomagnetic analyses in weak and strong magnetic fields, measurements of natural remanent magnetization and thermal demagnetization behavior, temperature dependence of strong field remanence imparted at 1.8 K, magnetic hysteresis, and first-order reversal curves. Additionally, scanning electron microscopy with energy-dispersive x-ray spectroscopy was employed to constrain the composition and grain size distribution of the magnetic mineral assemblage. At room temperature, the magnetic properties are dominated by multidomain FeNi alloys but low-temperature measurements reveal that the remanent magnetization signal is carried by non-stoichiometric chromite. The results indicate the importance of considering magnetic properties at cryogenic temperatures when studying the early Solar System and interpreting magnetic data from cold, extraterrestrial environments. The results also highlight the possibility of chromite playing a key role in the early stages of the formation of planetesimals