Kutterolf, S and Freundt, A and Druitt, TH and McPhie, J and Nomikou, P and Pank, K and Schindlbeck-Belo, JC and Hansteen, TH and Allen, S, The medial offshore record of explosive volcanism along the central to eastern Aegean Volcanic Arc, part 2: Tephra ages and volumes, eruption magnitudes and marine sedimentation rate variations, Geochemistry, Geophysics, Geosystems Article e2021GC010011. ISSN 1525-2027 (2021) [Refereed Article]
© 2021. The Authors. This is an open access article under the terms of the Creative Commons Attribution 4.0 International (CC BY 4.0) License, (https://creativecommons.org/licenses/by/4.0/) which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
We use the tephrostratigraphic framework along the Aegean Volcanic Arc established in part 1 of this contribution to determine hemipelagic sedimentation rates, calculate new tephra ages, and constrain the minimum magnitudes of (sub)plinian eruptions of thelast 200 kyrs. Hemipelagic sedimentation rates range from ~0.5 cm/kyr up to ~40 cm/kyr and vary laterally as well as over time. Interpolation between dated tephras yields an eruption age of ~37 ka for the Firiplaka tephra, showing that explosive volcanism on Milos is ~24 kyrs younger than previously thought. The four marine Nisyros tephras (N1 to N4) identified in part 1 (including the Upper (N1) and Lower (N4) Pumice) have ages of ~57 ka, ~63 ka, ~69 ka, and ~76 ka, respectively. Eruption ages for the Yali-1 and Yali-2 tephras are ~55ka and ~34 ka, respectively. The Yali-2 tephra comprises two geochemically and laterally distinct marine facies. The southern facies is identical to the Yali-2 fall deposit on land but the western facies has slightly less evolved glass compositions.
Overall, erupted plinian and co-ignimbrite fall tephra volumes range from < 1 to 56 km3 (excluding possible caldera fillings and ignimbite volumes), and 80% of the eruptions had magnitude 5.5 < M ≤ 7.2 (M = log(m)-7; m = erupted magma mass in kg). Twenty percent of the tephras represent 3.2 < M < 5.5 eruptions. The long-term average tephra magma mass flux through highly explosive eruptions of Santorini is estimated at ~40 kg/s. The analogous data for the Kos-Yali-Nisyros volcanic complex is less-well constrained but similar to Santorini.
|Item Type:||Refereed Article|
|Keywords:||tephrostratigraphy, Aegean Arc, chemical fingerprinting, volcanology|
|Research Division:||Earth Sciences|
|Research Field:||Stratigraphy (incl. biostratigraphy, sequence stratigraphy and basin analysis)|
|Objective Division:||Environmental Policy, Climate Change and Natural Hazards|
|Objective Group:||Natural hazards|
|Objective Field:||Geological hazards (e.g. earthquakes, landslides and volcanic activity)|
|UTAS Author:||McPhie, J (Professor Jocelyn McPhie)|
|UTAS Author:||Allen, S (Dr Sharon Allen)|
|Funding Support:||Australian Research Council (DP0449756)|
|Web of Science® Times Cited:||3|
|Deposited By:||CODES ARC|
|Downloads:||5 View Download Statistics|
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