SEDIMENTARY PETROCHRONOLOGY FOR DETRITAL PROVENANCE ANALYSIS: U-PB AND RARE-EARTH ELEMENT COMPOSITIONS IN ZIRCON FROM THE MODERN MISSISSIPPI RIVER DRAINAGE BASIN

Zircon geochronology is often paired with rare-earth elemental analysis to investigate the petrogenetic history of igneous and metamorphic rocks. The application of petrochronology has not been widely explored to decipher the sedimentary record due to the complexity of mixed-source detrital systems. To investigate the potential applications of detrital petrochronology, we present in situ rare-earth element compositions and U-Pb ages of zircon from the modern channel and bank sediment from the river systems that drain into the Gulf of Mexico. Samples of river sediment were taken from the Upper Missouri, Yellowstone, Platte, Kansas, Arkansas, Red, and Lower Mississippi Rivers. The current extent of North American drainages is well constrained, therefore we can directly correlate our observations to known sediment sources in the headwaters of the Mississippi River and its tributaries. We hypothesis that large orogenic systems have distinct chemical-age signatures, demonstrating the utility of detrital petrochronology.