Lithofacies from the 1963-1967 Surtsey eruption in SUSTAIN drill cores SE-2a, SE-2b and SE-03

A comprehensive analysis of drill cores from Surtsey, collected during the 2017 SUSTAIN project, reveals significant insights into the volcanic activity that shaped the island between 1963 and 1967. The study identified armoured lapilli tuff and lapilli tuff, primarily formed by explosive eruptions at Surtur, with notable intervals of coherent basalt likely representing intrusions that fed later lava flows. These findings challenge previous understandings, as the 2017 drill cores did not intersect a thick basalt interval found in earlier drilling, suggesting complex volcanic processes. The research also highlights extensive hydrothermal alteration and cement deposition, indicating the dynamic interaction between volcanic materials and seawater. Additionally, the angled drill hole SE-03 provided evidence that Surtur's eruptions excavated the pre-eruption sea floor to depths of several tens of meters.

McPhie, J., White, J. D. L., Gorny, C., Jackson, M. D., Gudmundsson, M. T., & Couper, S. (2020). Lithofacies from the 1963-1967 Surtsey eruption in SUSTAIN drill cores SE-2a, SE-2b and SE-03. Surtsey Research, 14, 19–32. https://doi.org/10.33112/surtsey.14.2