Speaker
Description
Reconstructing the eruptive history of Antarctic volcanoes is particularly challenging due to extensive ice cover, limited outcrop exposure, and logistical constraints. In this study, we investigate three englacial tephra layers (DPT 1, DPT 2, and DPT 3) preserved within an ice sequence at 2581 m a.s.l. on the southwestern flank of Mount Melbourne (Northern Victoria Land, Antarctica). A comprehensive approach combining field observations, textural analyses and detailed geochemical characterization of volcanic glass shards was integrated with multivariate statistical methods, including hierarchical clustering, principal component analysis (PCA), and t-distributed stochastic neighbor embedding (t-SNE).
The results reveal that the investigated tephra layers originate from Mount Melbourne volcano and represent three distinct and previously unrecognized explosive eruptions. Evidences indicates that DPT 1 corresponds to the most energetic, possibly Subplinian event, whereas DPT 2 and DPT 3 record less intense eruptive phases occurring in close succession. Statistical analysis highlights subtle yet significant compositional differences, allowing identification of distinct geochemical clusters and improving correlation with existing datasets.
Although precise dating remains uncertain, stratigraphic constraints suggest a recent, potentially historical age for these eruptions. This study demonstrates the critical role of englacial tephra archives in preserving otherwise inaccessible volcanic records and highlights the effectiveness of integrating geochemical fingerprinting with advanced statistical methods to resolve complex compositional relationships. The proposed approach provides a robust framework for refining eruptive histories and contributes to improving volcanic hazard assessment in remote, ice-covered volcanic regions.