Properties, age, and significance of dunes near Snow Water Lake, Elko County, Nevada
Autor: | Jeffrey S. Munroe, Andrew L. Gorin, Noah N. Stone, William H. Amidon |
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Rok vydání: | 2017 |
Předmět: |
Hydrology
010506 paleontology Lithology Geochemistry Sediment engineering.material 010502 geochemistry & geophysics Snow 01 natural sciences Arts and Humanities (miscellaneous) Loam Dendrochronology engineering General Earth and Planetary Sciences Plagioclase Precipitation Holocene Geology 0105 earth and related environmental sciences Earth-Surface Processes |
Zdroj: | Quaternary Research. 87:24-36 |
ISSN: | 1096-0287 0033-5894 |
DOI: | 10.1017/qua.2016.5 |
Popis: | Dunes adjacent to the Snow Water Lake playa in Elko County of northeastern Nevada rise up to ~10 m above the playa surface in seven distinct clusters. The dunes are composed of tan silty loam containing calcite, quartz, plagioclase, and dioctahedral clay. Abundances of trace elements, along with relative proportions of quartz and calcite, are distinct between dunes along the north and south sides of the playa, reflecting proximity to streams draining different lithologies in the neighboring mountains. Luminescence (optically stimulated luminescence and infrared-stimulated luminescence) dating of dune crest samples demonstrates that the last episode of dune accumulation occurred in the mid-eighteenth century. Moisture-sensitive tree ring records from a nearby site indicate that dune accumulation coincided with an interval of below-average precipitation immediately following a very wet decade. This sequence is consistent with models requiring wetter climatic conditions to move coarse sediment onto a playa surface, followed by dune building under drier conditions. Younger luminescence ages from a sand-dominated unit exposed in an arroyo cut through the dunes may reflect a wetter, more erosive climatic regime ca. AD 1800. The Snow Water Lake dunes are currently eroding, signaling a reduction in the amount of sediment reaching the playa. |
Databáze: | OpenAIRE |
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