Extending the late holocene tephrochronology of the central Kenai Peninsula, Alaska

Blackford, Jeffrey J.; Payne, Richard J.

Abstract

Tephrochronology, the reconstruction of past volcanic ash deposition, provides a valuable method for dating sediments and determining long-term volcanic history. Tephra layers are highly numerous in Alaska, but knowledge of their occurrence and distribution is incomplete. This study expands the regional tephrochronology for the Kenai Peninsula of south-central Alaska by investigating the tephrostratigraphy of two peatland sites. We located seven visible tephras and seven microtephras and investigated the particle size and geochemistry of the visible tephras. Radiocarbon dates were used to estimate the timescale of each core. Geochemical comparison showed that the visible tephras originated from late Holocene eruptions of Augustine, Crater Peak-Mt. Spurr, and Hayes volcanoes. Some of the tephras had been documented previously, and these new findings expand their known range. Others represent eruptions not previously reported, including a Crater Peak-Mt. Spurr eruption around 430 cal. BP. The results provide new tephra data for the region, illustrate the spatial heterogeneity of tephra deposition, and show the potential of microtephras for expanding the regional tephra record. © The Arctic Institute of North America.

Citation

Blackford, J. J., & Payne, R. J. (2008). Extending the late holocene tephrochronology of the central Kenai Peninsula, Alaska. Arctic, 61(3), 243-254. https://doi.org/10.14430/arctic22

• Journal Article Type: Article
• Online Publication Date: Aug 25, 2009
• Publication Date: Sep 1, 2008
• Deposit Date: Nov 13, 2014
• Publicly Available Date: Nov 23, 2017
• Journal: Arctic
• Print ISSN: 0004-0843
• Publisher: Arctic Institute of North America
• Peer Reviewed: Peer Reviewed
• Volume: 61
• Issue: 3
• Pages: 243-254
• DOI: https://doi.org/10.14430/arctic22
• Keywords: Tephra; Cryptotephra; Peatlands; Alaska; Volcanoes; Electron probe microanalysis
• Public URL: https://hull-repository.worktribe.com/output/470863
• Publisher URL: http://arctic.journalhosting.ucalgary.ca/arctic/index.php/arctic/article/view/22
• Additional Information: Authors' accepted manuscript of article published in: Arctic, 2008, v.61, issue 3.
• Contract Date: Nov 23, 2017