Reconstructing the past eruption history of Campi Flegrei, Italy

Reconstructing the past eruption history of Campi Flegrei, Italy

How has the tempo and magnitude of volcanism at Campi Flegrei changed over its life cycle, and what controls it?

More than 3 million people live within 10 km of the active Campi Flegrei volcano in Naples, Italy. Campi Flegrei is currently in a state of unrest with magma accumulating beneath the volcano. Current hazard assessments are solely based on the magnitude and frequency of the most recent eruptions and do not account for the full extent of the style and frequency of activity at the volcano. This project aims to obtain longer term and detailed geological and geochronological datasets to further understand eruptive behaviour at Campi Flegrei.

A Grand Challenge in Volcanology is to quantify the life cycles of volcanoes worldwide to overcome our current biased understanding. Forecasting the style and magnitude of future eruptions at a particular volcano is often based on what happened in the recent past, because the deposits are well preserved and easy to access. However, since these short-term records do not represent the full range of volcanic activity or variations in eruption frequency, hazards assessments for these volcanoes are likely to be inaccurate and inadequate. Campi Flegrei was the source of one of the largest explosive eruptions in the late Pleistocene (Campanian Ignimbrite at ~40 ka) but little is known of the longer-term volcanic activity prior to the caldera-forming eruptions, which buried older eruption deposits.

We now have the opportunity to investigate this longer-term history using numerous marine cores from in the Tyrrhenian, Ionian and Adriatic Seas around Italy. We will correlate the volcanic deposits preserved in the marine sediments with those around the caldera to build up detailed eruption stratigraphy. This stratigraphy will be placed on a temporal scale by obtaining 40Ar/39Ar ages of the deposits and combining them with existing data in Bayesian age-depth models. The glass and mineral data of the volcanic deposits, which will primarily be used to correlate the layers, will also provide information on magma evolution.

These detailed and temporally constrained datasets will provide insight into the controls on volcanism at Campi Flegrei and help refine hazard and risk assessments.

Aims of the Project

Obtain long term and detailed geological and geochronological datasets to further understand eruptive behaviour at Campi Flegrei, Italy

Methods to be used

Field mapping, core sampling, cryptotephra analysis, electron microprobe analysis, laser-ablation inductively coupled mass spectrometry, and Argon dating

Specialised skills needed

Background in geology or geography

If interested, please contact Victoria Smith victoria.smith@rlaha.ox.ac.uk