Patagonian ash on sub‐Antarctic South Georgia: expanding the tephrostratigraphy of southern South America into the Atlantic sector of the Southern Ocean. (4th May 2018)

• Record Type: Journal Article
• Authors: Oppedal, Lea Toska; van der Bilt, Willem G. M.; Balascio, Nicholas L.; Bakke, Jostein
• Is Part Of: Journal of quaternary science. Volume 33:Number 5(2018)
• Page Start: 482
• Page End: 486
• Publication Date: 2018-05-04
• Subjects: late Holocene -- South Georgia -- Southern Ocean -- sub‐Antarctic -- tephra; Geology, Stratigraphic -- Quaternary -- Periodicals; Paleontology -- Quaternary -- Periodicals; 551.79
• DOI: 10.1002/jqs.3035
• Languages: English
• ISSNs: 0267-8179

Abstract

ABSTRACT: Fingerprinting non‐visible volcanic ash (cryptotephra) enables precise dating and time synchronization of palaeoclimate archives. Recent analytical advances allow us to strengthen and expand existing tephrostratigraphical frameworks and harness the full potential of this powerful geochronological tool. Here, we present geochemical (electron microprobe) and chronological ( 14 C) evidence to show that ash found in a peat section on the sub‐Antarctic island of South Georgia correlates to the ∼2950 cal a BP Alpehué eruption of the Chilean Sollipulli volcano. This discovery marks the first tephra fingerprint on South Georgia and expands the recently refined tephrostratigraphy of Patagonia ∼3000 km into the Southern Ocean. As deposition of this tephra horizon coincides with a major shift in regional atmospheric conditions, future finds may yield information on the spatiotemporal pattern of Southern Ocean climate dynamics.