EXAMINING FAR-FLUNG VS LOCAL FLUVIAL DELIVERY TO THE NEUQUÉN BASIN IN ARGENTINA THROUGH DETRITAL-ZIRCON U-Pb GEOCHRONOLOGY

The Neuquén Basin of Argentina, located in the northern region of Patagonia, served as a repository for sediment during the Cretaceous period. Though previous work has been done to explore sources of far-flung sediment deposition to the basin, this research is minimal and only includes samples from the Pilmatué Member of the Agrio Formation which had detrital-zircon age distributions ranging from ca. 130-3300 Ma. The intention of my work is to broaden this current dataset, with my samples being from the Rayoso Formation and the Neuquén Group. For my analysis following mineral separation, I used a scanning electron microprobe to collect backscatter electron images and performed laser ablation-multicollector-inductively coupled plasma mass spectrometry (LA-MC-ICPMS) to analyze zircon grains for U-Pb isotopes. For my samples from the Rayoso Formation, I found the detrital-zircon age distributions to be primarily clustered between ca. 135-1200 Ma. For my samples from the Neuquén Group, I found the detrital-zircon age distributions to be primarily clustered between ca. 100-200 Ma. I will be comparing my findings with data from the Saldania Belt, the Sierra de la Ventana Belt, and others to investigate them as possible depositional sources.