Phlegrean Fields Volcanism

Dr Marcello Di Bonito has recently undertaken research, jointly with Dr Gianfilippo De Astis and Dr Monica Piochi of the Istituto Nazionale di Geofisica e Vulcanologia (INGV) in Italy, on the volcanic activity in the Phlegrean Fields, Naples, Italy. The project was run under the SPUR scheme at Nottingham Trent University and benefited from the work of two students from current BSc courses as well as the collaboration with two different departments of the British Geological Survey for some of the analyses.

The Phlegrean Fields are a densely inhabited active volcanic field, with one of the highest associated volcanic risks on Earth. Its caldera partly includes the western portion of Naples and largely reflects the high-magnitude eruptions of the Campanian Ignimbrite (39 ka) and the Neapolitan Yellow Tuff (15 ka). The project aimed at comparing findings from newly sampled areas with already available data. Some of the objectives were to estimate the depth of the reservoirs originating the upraising magma, possibly after recharge and mixing, and the mechanisms triggering new eruption within the Phlegrean Fields. This will constitute an important base model of the caldera’s plumbing system and its variation with time, which can in turn represent an important tool to define and better understand the volcanic hazard linked to this urban settlement.

The images show minerals observed in thin sections from different samples taken during the project: on the left are mineral phases observed under polarised light, on the right an image generated under microprobe environment (Clinopyroxene and Plagioclase in matrix).