Evidence for a large magnitude eruption from Campi Flegrei caldera (Italy) at 29 ka

Journal article

The 40 ka caldera-forming eruption of Campi Flegrei (Italy) is the largest known eruption in Europe during the last 200 kyr, but little is known about other large eruptions at the volcano prior to a more recent caldera-forming event at 15 ka. At 29 ka a widespread volcanic ash layer, termed the Y-3 tephra, covered >150,000 km2 of the Mediterranean. The glass compositions of the layer are consistent with Campi Flegrei being the source but no prominent proximal equivalent in the appropriate chrono-stratigraphic position had been previously identified. Here we report new glass chemistry data and 40Ar/39Ar ages (29.3 ± 0.7 ka [2σ]) that reveal the near-source Y-3 eruption deposit in a sequence at Ponti Rossi and a nearby borehole (S-19) in Naples. The dispersal and thickness of the deposits associated with this eruption, herein named the Masseria del Monte Tuff, were simulated using a tephra sedimentation model. The model indicates that ~16 km3 DRE (dense rock equivalent) of the magma erupted was deposited as fall. This volume and the areal distribution suggest the Masseria del Monte Tuff was a magnitude 6.6 eruption (corresponding to VEI 6), similar to the 15 ka caldera-forming Neapolitan Yellow Tuff (M6.8) eruption at Campi Flegrei. However, the lack of coarse, thick, traceable, near-vent deposit suggests peculiar eruption dynamics. Our reconstruction and modelling of the eruption show the fundamental role that distal tephrostratigraphy can play in constraining the scale and tempo of past activity, especially at highly productive volcanoes

Authors: Albert, PG; Giaccio, B; Isaia, R; Costa, A; Niespolo, EM

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Geological Society of America
• Journal: Geology
• Volume: 47
• Issue: 7
• Pages: 595-599
• Publication date: 2019-04-25
• Acceptance date: 2019-03-31
• DOI: 10.1130/G45805.1
• EISSN: 1943-2682
• ISSN: 0091-7613
• Language: English
• Keywords: FFR