Short communication: Driftwood provides reliable chronological markers in Arctic coastal deposits

• Published in: Geochronology
• Main Authors: L. Sander, A. Kirdyanov, A. Crivellaro, U. Büntgen
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2021
• Subjects: Geology; QE1-996.5; Stratigraphy; QE640-699; laptev; Laptev Sea; lena delta; lena river
• Online Access: https://doi.org/10.5194/gchron-3-171-2021; https://doaj.org/article/47849c4df4794c5ab50f2b94b422ea8c

Originating from the boreal forest and often transported over large distances, driftwood characterizes many Arctic coastlines. Here we present a combined assessment of radiocarbon ( 14 C ) and dendrochronological (ring width) age estimates of driftwood samples to constrain the progradation of two Holocene beach-ridge systems near the Lena Delta in the Siberian Arctic (Laptev Sea). Our data show that the 14 C ages obtained on syndepositional driftwood from beach deposits yield surprisingly coherent chronologies for the coastal evolution of the field sites. The dendrochronological analysis of wood from modern drift lines revealed the origin and recent delivery of the wood from the Lena River catchment. This finding suggests that the duration of transport lies within the uncertainty of state-of-the-art 14 C dating and thus substantiates the validity of age indication obtained from driftwood. This observation will help us better understand the response of similar coastal systems to past climate and sea-level changes.