Celebration of Scholarship and Creative Activity 2023
The Ross orogenic belt in Antarctica is one of several Neoproterozoic-early Paleozoic mountain belts that formed in association with the assembly of the Gondwana supercontinent. Although the erosional remnants of the mountain belt have been the subject of study for over a century, there are outstanding questions about the nature and age of magmatism and its relation to deformation. My research focuses on the formation and evolution of an intrusive igneous rock body that occurs near the mouth of the Beardmore Glacier in the Transantarctic Mountains of Antarctica. I obtained a sample of this intrusive rock from the US Polar Rock Repository. Hand sample and petrographic analyses indicate it is medium grained, porphyritic to equigranular granitoid with microcline and plagioclase feldspar, quartz, biotite (altered to chlorite), and other minor accessory phases. Heavy mineral separation yielded zircon and apatite grains. SEM imaging shows euhedral zircon crystals with oscillatory zonation with some grains possessing inherited cores, indicating zircon inheritance from parent rocks melted during evolution of the magma. Age analyses of zircon and apatite will provide information on the timing of magmatism, preintrusive deformation, and subsequent cooling associated with the evolution of the Ross orogenic belt. They also have the potential to provide information about the ages of rocks that melted during magmatic evolution.