Abstract: This project studies remnant magnetization in igneous rocks from the Dufek igneous complex, Antarctica. Its primary goal is to understand variations in the Earth's magnetic field during the Mesozoic Dipole Low (MDL), a period when the Earth's magnetic field underwent dramatic weakening and rapid reversals. This work will resolve the MDL's timing and nature, and assess connections between reversal rate, geomagnetic intensity and directional variability, and large-scale geodynamic processes. The project also includes petrologic studies to determine cooling rate effects on magnetic signatures, and understand assembly of the Dufek as an igneous body. Poorly studied, the Dufek is amongst the world's largest intrusions and its formation is connected to the break-up of Gondwana. The broader impacts of this project include graduate and undergraduate education and international collaboration with a German and Chilean IPY project.