Smith Canyon dune field, Washington, U. S. A: relation to glacial outburst floods, the Mazama eruption, and Holocene paleoclimate

摘要

Sedimentary deposits from the Smith Canyon dune field, south-central Col- umbia Basin, Washington, U. S. A. document climatically-influenced Late Pleistocene and Holocene aeolian and fluvial deposition in a region impacted By glacial outburst floods and tephra falls. The depositional history is sum- Marized by five environmentally distinctive and climatically sensitive sedimen- Tary units (temporal limits estimated): Unit 1 (c. 15. 5 -8 ka), pedogenically Altered glacial outburst flood and minor aeolian silt and clay; Unit 2 (c. 8-6.9 ka), fluvial and minor aeolian sand; Unit 4 (c. 6.8-3.9 ka), aeolian dune sand; Unit 5 (c. 3.9 ka to present), pedogenically altered, stabilized dune sand.