Detrital zircon geochronology of quartzite clasts, northwest Wyoming: Implications for Cordilleran Neoproterozoic stratigraphy and depositional patterns

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U-Pb ages of detrital zircons extracted from quartzite clasts (n=857), 11 sampling localities in Cretaceous and Tertiary conglomerates in Jackson Hole and the Bighorn Basin in northwest Wyoming, reveal that the source of these clasts is Neoproterozoic in age. We collected multiple clasts at ten of the sampling localities and co-mingled the extracted zircons; we analyzed zircons from a single clast at the eleventh locality. The maximum depositional age of the ten composite samples is 1016±18Ma. The principal peak ages for the aggregate of these clasts are 1715 and 1791Ma, and about 50% of all zircon grains yield Yavapai-Mazatzal ages (∼1600–1800Ma). Other age peaks are 1844 and 1918Ma (various Paleoproterozoic orogenic provinces), 2711Ma (Wyoming Province), 1444 (Mid-continent Granite-Rhyolite Province), and 1100Ma (Grenville Province). The detrital zircon age spectra indicate a significant distal provenance in eastern and southern Laurentia for these quartzite clasts. The maximum depositional age for these quartzite clasts is 1016Ma, which is too young for these quartzite clasts to be correlative to the Belt-Purcell Supergroup (∼1390–1470Ma) to the north. We interpret that the principal source rock for these quartzite is most likely the Neoproterozoic lower Brigham Group of southeastern Idaho. The most likely source was rocks was the upper plate of the Paris thrust sheet. The source was either completely eroded away during the Neogene, and/or was buried by Snake River Plain volcanism. This correlation requires the Brigham Group to occur much more extensively to the north than current mapping indicates.