| Summary: | Holocene tephrostratigraphy in Alaska provides independent chronology and stratigraphic correlation in a region where reworked old (Holocene) organic carbon can significantly distort radiocarbon chronologies. Here we present new glass chemistry and chronology for Holocene tephras preserved in three Alaskan lakes: one in the eastern interior, and two in the southern Brooks Range. Tephra beds in the eastern interior lake-sediment core are correlated with the White River Ash and the Hayes tephra set H (~4200-3700 cal yr BP), while an additional discrete tephra bed is likely from the Aleutian Arc-Alaska Peninsula. Cryptotephras (non-visible tephras) found in the Brooks Range include the informally named "Ruppert tephra" (~2700-2300 cal yr BP), and the Aniakchak caldera-forming event II tephra (CFE II; ~3600 cal yr BP). A third underlying Brooks Range cryptotephra is chemically indistinguishable from the Aniakchak CFE II tephra (4070-3760 cal yr BP) and is likely to be from an earlier eruption of the Aniakchak volcano.
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