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Applying detrital zircon geochronology to identify variations in sedimentary provenance of the Cretaceous Straight Cliffs Formation, Southern Utah. Tyler Szwarc Advisor: Cari Johnson. UT. CO. AZ. NM. Late Cretaceous (~85 Ma). http://www2.nau.edu/rcb7/ColoPlatCret_PictCliffs.jpg.
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Applying detrital zircon geochronology to identify variations in sedimentary provenance of the Cretaceous Straight Cliffs Formation, Southern Utah Tyler SzwarcAdvisor: Cari Johnson
UT CO AZ NM Late Cretaceous (~85 Ma) http://www2.nau.edu/rcb7/ColoPlatCret_PictCliffs.jpg
Previous Research • Sedimentary provenance changes across sequence boundaries Lawton et al., 2003
Project Overview • Infer sedimentary provenance of John Henry Member, Straight Cliffs Formation • Use detrital zircon ages from ~20 sandstone samples as “tracers” • Look for changes in provenance through time and space
What is a Detrital Zircon? • Silicate mineral that forms in felsic igneous melts • Incorporates radioactive uranium into the crystal • U/Pb ratio provides crystallization age • “detrital” implies the zircon has been transported from origin
Dickinson and Gehrels, 2008 UT CO Sevier Fold/Thrust Belt CO UT AZ NM Mogollon Highlands Late Cretaceous (~80 Ma) http://www2.nau.edu/rcb7/ColoPlatCret_PictCliffs.jpg
Importance • Provenance studies help determine spatial extent of sandstones • Better understand the nature of sequence boundaries in fluvial strata • Obtain a better understanding of foreland basin evolution
References • Blakey, Ron, 2011, Paleogeography of the Colorado Plateau and Vicinity, http://www2.nau.edu/rcb7/ColoPlatPalgeog.html • Dickinson, W., and Gehrels, G., 2008. Sediment delivery to the Cordilleran Foreland Basin: Insights from U-Pb ages of detrital zircons in upper Jurassic and Cretaceous strata of the Colorado Plateau. American Journal of Science, vol. 308, December 2008, P. 1041 – 1082. • Lawton, T., Polluck, S., and Robinson, R., 2003. Integrating sandstone petrology and nonmarine sequence stratigraphy: Application to the Late Cretaceous fluvial systems of southwestern Utah, U.S.A., Journal of Sedimentary Research, vol. 73, No. 3, May 2003, P. 389 – 406.