2025/07/09 by Antonio M. Álvarez‐Valero, Hirochika Sumino, R. Burgess +12 · 1 voice · 1 citation
Earth and Planetary Sciences · Biochemistry, Genetics and Molecular Biology · #Geology and Paleoclimatology Research #Geomagnetism and Paleomagnetism Studies #Geological and Geochemical Analysis
paper · pdf · doi:10.1038/s41598-025-03925-5
openalex publication_date 2025/07/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
Cosmogenic nuclei production for dating the Earth surface exposure of rock/mineral samples, especially 3 He, is a robust technique in geochronology. We describe its application to constrain the ages of key eruptive episodes of the volcanic history of Deception Island (Antarctica): (i) the volcanic products of the island formed before the caldera collapse (pre-caldera material); and (ii) the caldera-forming event (syn-caldera material). High 3 He/ 4 He ratios (up to 910 R A ; R A = 1.39 × 10 –6 ) in the crystal structure of olivine phenocrysts measured through total fusion He release are much higher than the magmatic values previously obtained in the inclusions of the same olivines obtained by hydraulic crushing. Such high values indicate a cosmogenic origin and reveal an age of c. 4 Ma for the pre-caldera material, and c. 4.6 ka and 170 ka for the syn-caldera deposits. The result of c. 4.6 ka for the caldera collapse episode is consistent with previous age estimations based on tephrochronology, whereas the c. 170 ka result reveals the presence of pre-caldera olivines embedded in the syn-caldera deposits that experienced less exposure to cosmic rays compared to the samples with ages of 4 Ma. This oldest age estimate represents the first quantitative geochronological approach attempting to date Deception Island formation.