Volcanic glass from the 1.8 ka Taupō eruption (New Zealand) detected in Antarctic ice at ~ 230 CE

Abstract

Chemical anomalies in polar ice core records are frequently linked to volcanism; however, without the presence of (crypto)tephra particles, links to specific eruptions remain speculative. Correlating tephras yields estimates of eruption timing and potential source volcano, offers refinement of ice core chronologies, and provides insights into volcanic impacts. Here, we report on sparse rhyolitic glass shards detected in the Roosevelt Island Climate Evolution (RICE) ice core (West Antarctica), attributed to the 1.8 ka Taupō eruption (New Zealand)—one of the largest and most energetic Holocene eruptions globally. Six shards of a distinctive geochemical composition, identical within analytical uncertainties to proximal Taupō glass, are accompanied by a single shard indistinguishable from glass of the ~25.5 ka Ōruanui supereruption, also from Taupō volcano. This double fingerprint uniquely identifies the source volcano and helps link the shards to the climactic phase of the Taupō eruption. The englacial Taupō-derived glass shards coincide with a particle spike and conductivity anomaly at 278.84 m core depth, along with trachytic glass from a local Antarctic eruption of Mt. Melbourne. The assessed age of the sampled ice is 230 ± 19 CE (95% confidence), confirming that the published radiocarbon wiggle-match date of 232 ± 10 CE (2 SD) for the Taupō eruption is robust.

Problems of Dating Spread on Radiocarbon Calibration Curve Plateaus: The 1620–1540 BC Example and the Dating of the Therasia Olive Shrub Samples and Thera Volcanic Eruption

“…However, comparison of radiocarbon dates—such as the dates on the Therasia olive shrub—with radiocarbon dates on contemporary samples from contexts associated with the Thera eruption or its impacts from elsewhere in the Aegean well away from Thera allow us to test for, and dismiss, this concern (Manning 2022; Pearson et al 2023). In further general support the case of the earlier 1st millennium AD Taupo volcanic eruption in New Zealand may also be noted: here independent ice-core chronology has recently supported/confirmed the date derived from radiocarbon dating of associated regional tree-ring series and other samples and refuted a suggestion that there was perhaps a substantial volcanic CO 2 age bias across a large area (Piva et al 2023).…”

“…Definitive (hopefully) dating of the Thera eruption will likely come from recognition of volcanic products specifically (or very likely) from the Minoan eruption of the Thera volcano in a well-dated high-resolution environmental archive: probably an ice-core (and ideally replicated). The recent recognition of Taupo eruption rhyolitic glass shards in the Roosevelt Island Climate Evolution (RICE) ice core (West Antarctica) offers an example (Piva et al 2023). Until that time radiocarbon can serve to narrow the likely dating window.…”

The Response of Taupō Volcano to the M7.8 Kaikōura Earthquake

“…Here, we present evidence that in addition to slow slip and microseismicity, the Kaikōura earthquake triggered distinctive local deformation at Taupō volcano, 500 km north of the earthquake's epicenter. Taupō is a silicic volcano that last erupted ∼1,800 years ago (Hogg et al., 2012; Piva et al., 2023; Wilson & Walker, 1985), expelling ∼35 km 3 of material (Davy & Caldwell, 1998). Despite Taupō’s propensity for large and violent eruptions (Wilson, 2001), in historic times the caldera has undergone periods of unrest only, with no accompanying eruption (Barker et al., 2021; Illsley‐Kemp et al., 2021; Journeau et al., 2022; Peltier et al., 2009; Potter et al., 2015).…”