Postdoctoral Fellowship: EAR-PF: Petrochronometers as provenance proxies: implications for the spatio-temporal evolution of continental collision to escape

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Dr. Megan Mueller has been awarded an NSF EAR Postdoctoral Fellowship to conduct research and educational activities at the University of Arizona alongside mentor Dr. Mauricio Ibañez-Mejia. Sedimentary provenance analysis is widely used across the Earth sciences to reconstruct ancient sediment dispersal networks, source-to-sink sediment budgets, sedimentary basin evolution, and to discern links between tectonics, paleogeography, climate, and biology. However, provenance methods that exclusively focus on studying the age distributions and chemistry of the mineral zircon (ZrSiO4) in sedimentary environments are limited in tracking detritus sourced from mafic and metamorphic rocks. This limitation is especially pronounced in continental collision settings, where obducted fragments of oceanic crust and exhumed metamorphic massifs are common sources of sediment but whose cryptic provenance signatures impose limits on the ability to perform accurate geodynamic and paleogeographic reconstructions. This research investigates the applicability of combined traditional and non-traditional sedimentary provenance methods to reconstruct sedimentary provenance during the transition from continental collision to tectonic escape in the Ulukisla Basin in south-central Turkiye. This study develops workflows for novel, emerging sedimentary provenance techniques that can be applied to tectonic settings worldwide and aid in addressing outstanding questions in the Earth sciences. The project supports field- and laboratory-based training and research experience for undergraduate students in the United States and Turkiye.Accurately reconstructing the timing and dynamics of continental collisions in modern and deep-time settings remains a key challenge for the tectonics community. However, a growing body of work suggests that sedimentary basins may hold the most complete record of subduction, accretion, collision, and escape. Utilizing the deformational, magmatic, and metamorphic information preserved in detrital minerals thereby provides a way to unite proxy records into a holistic model of collisional evolution. This project leverages the U-Pb, Hf, Nd, and trace element composition of detrital zircon, rutile, and titanite, to track sedimentary provenance from igneous and metamorphic sources. This study will create a proof-of-concept workflow for detrital petrochronology applied to sedimentary basin analysis. Furthermore, these datasets establish quantitative relationships between the timing, tempo, and spatial extent of magmatism, metamorphism, deformation, crustal thickness, and exhumation. Using this multi-proxy approach, this project aims to document the spatial and temporal evolution of continental collision and tectonic escape. The results will inform future work in sedimentary provenance analysis and continental collision settings from modern and ancient orogens.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.