Bridging the gap: 40Ar/39Ar dating of volcanic eruptions from the 'Age of Discovery'

Preece, K., Mark, D. F. , Barclay, J., Cohen, B. E. , Chamberlain, K. J., Jowitt, C., Vye-Brown, C., Brown, R. J. and Hamilton, S. (2018) Bridging the gap: 40Ar/39Ar dating of volcanic eruptions from the 'Age of Discovery'. Geology, 46(12), pp. 1035-1038. (doi: 10.1130/G45415.1)

Abstract

Many volcanoes worldwide still have poorly resolved eruption histories, with the date of the last eruption often undetermined. One such example is Ascension Island, where the timing of the last eruption, and consequently, the activity status of the volcano, is unclear. Here, we use the 40Ar/39Ar dating technique to resolve ages of the three youngest lava flows on the island, which are hawaiites and mugearite with 1.5–1.9 wt% K2O. In dating these lavas, we provide the first evidence of Holocene volcanic activity on Ascension (0.51 ± 0.18 ka; 0.55 ± 0.12 ka; 1.64 ± 0.37 ka), determining that it should be classed as an active volcanic system. In addition, we demonstrate that the 40Ar/39Ar method can reproducibly date mafic lava flows younger than 1 ka, decreasing the gap between recorded history and geological dating. These results offer new prospects for determining patterns of late-Holocene volcanic activity; critical for accurate volcanic hazard assessment.

• Item Type: Articles
• Additional Information: This work was funded by a Leverhulme Trust Research Project Grant (RPG-2013–042).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Mark, Professor Darren and Cohen, Dr Benjamin and Preece, Dr Katie
• Authors: Preece, K., Mark, D. F., Barclay, J., Cohen, B. E., Chamberlain, K. J., Jowitt, C., Vye-Brown, C., Brown, R. J., and Hamilton, S.
• College/School: College of Science and Engineering > School of Geographical and Earth Sciences; College of Science and Engineering > Scottish Universities Environmental Research Centre
• Journal Name: Geology
• Publisher: Geological Society of America
• ISSN: 0091-7613
• ISSN (Online): 1943-2682
• Published Online: 09 November 2018
• Copyright Holders: Copyright © 2018 Geological Society of America
• First Published: First published in Geology 46(12):1035-1038
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher