2018/11/09 by Katie Preece, Darren F. Mark, Jenni Barclay +6 · 42 citations
Earth and Planetary Sciences · Social Sciences · #Geology and Paleoclimatology Research #Geological and Geochemical Analysis #Pacific and Southeast Asian Studies #Bridging (networking) #Library science #History #Art history #Computer science
paper · open access · doi:10.1130/g45415.1
published in Geology 46(12), 1035-1038 (Geological Society of America)
openalex publication_date 2018/11/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/08
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.