DETRITAL ZIRCON PROVENANCE OF SAND DUNES IN THE WYOMING WIND CORRIDOR

The Wyoming wind corridor comprises three active dune fields in the Greater Green River Basin of south-central Wyoming: The Killpecker, Ferris, and Seminoe dune fields. The origin of sediment as well as the connectivity between these dune fields is poorly understood, with multiple sediment sources for a single dune field having been suggested in earlier work. Detrital zircons found in these dune fields may provide insight into the source of sand. This study provides 448 new detrital zircon U-Pb ages collected via LA-ICP-MS for five samples across the three dune fields.

The detrital zircon age distribution of the Killpecker dune field shows major age peaks at 52 and 2534 Ma. Seminoe dune field has major age peaks at 93, 1385, and 1719 Ma, and Ferris has a large peak at 2612 Ma. The major Phanerozoic grain age population for Killpecker dunes may be indicative of the Absaroka Volcanics (43-53 Ma), while major Precambrian age populations in all three dune fields are consistent with published ages of local basement uplifts such as the Wind River Range and the deeply eroded Granite Mountains.

Detrital zircon U-Pb age distributions of samples from the three dune fields suggests that they are strongly influenced by local sediment sources. This is statistically supported by Kolmogorov–Smirnov tests in which the p-values between each dune field are significantly less than 10^-3.

Future studies in these dune fields will provide clues to the erosional and depositional systems occurring in the area at the time of the dunes formation about 10,000 years ago. This project provides additional zircon data to the central Wyoming area, as well as further understanding of zircon-rich aeolian deposits that may have future economic value.