Gareth Fabbro

• BA, MSci, PhD
• Lecturer in Igneous Processes at University of East Anglia

Caldera-forming eruptions at Santorini discharge large volumes of silicic magma from upper crustal reservoirs. Sequences of smaller eruptions preceding the main explosive eruptions can provide insight into the conditions of the plumbing system that lead to caldera-forming events, which is important for interpreting monitoring data. We analysed text...

The size of eruptions from calderas varies greatly, from small effusive eruptions that pose danger only in the immediate vicinity of the vent, to large, caldera-forming events with global impact. However, we currently have little way of knowing the size of the next eruption. Here, we focus on Rabaul Caldera, Papua New Guinea, to investigate differe...

The Philippine Island Arc has a large number of volcanoes with diverse morphologies, making it an ideal location to study the factors controlling the morphology and spatial distribution of island arc volcanoes. We have identified 731 volcanic edifices using the SRTM 30 m digital elevation models, and computed their quantitative morphology using the...

Pre-eruptive processes and their timescales are critical information for risk management at explosive volcanoes, and Santorini caldera (Greece) provides an excellent context in which to approach this subject. We ask two questions. First, are pre-eruptive processes the same for small and big eruptions? To investigate, we performed a multi-mineral di...

Oceanic Large Igneous Provinces (LIPs) usually have abnormally thickened oceanic crusts and complex magma plumbing systems. Investigating the magma plumbing systems of LIPs is crucial for understanding the dynamic evolution of our Earth. The submarine Shatsky Rise oceanic plateau is the third largest oceanic plateau on Earth and reaches a maximum c...

Despite the economic and ecological importance of corals’ skeletal structure, as well as their predicted vulnerability to future climate change, few studies have examined the skeletal mechanical properties at the nanoscale. As climate change is predicted to alter coral growth and physiology, as well as increase mechanical stress events (e.g., bioer...

The ratio of barium to calcium in coral skeletons (Ba/Ca coral ) is broadly used as a proxy for tracking terrestrial/river runoff. There are, however, inconsistencies in Ba/Ca coral records that have prompted caution in its reliability as an environmental proxy. Direct comparisons between in-situ seawater measurements and coral Ba/Ca are therefore...

Studies of the products of the activity precursory to caldera-forming events are essential in revealing how caldera systems evolve in the prelude to climactic eruptions. Here, we investigate the deposits formed by the Talili Pyroclastics eruption sequence, which preceded the youngest major eruptive event, the seventh century CE (1400 BP) Rabaul Pyr...

Rhyolitic magmas have rarely erupted during historical times, thus we have a poor record of the signals of unrest that precede them. The Laguna del Maule volcanic field (LdM), Chile, is in the midst of a decade-long episode of unrest including surface inflation at more than 200 mm/yr. Geomorphic observations indicate that many similar deformation e...

Many calderas have a history of repeated caldera-forming eruptions, interspersed with periods of more minor activity. Rabaul, for instance, has had at least 11 ignimbrite-forming eruptions over the last 200 ky. The most recent of these was the ‘1400 BP’ eruption, which led to caldera collapse. Since then, there has been multiple smaller eruptions,...

The 1400BP eruption of Rabaul discharged >11km3 of mainly crystal-poor dacitic magma, and collapsed a caldera. Following an initial Plinian phase, multiple pyroclastic flows were emplaced. We have sampled throughout the eruptive sequence: the Plinian fall deposit, basal surge unit, the base and top of the massive ignimbrite, and the uppermost ignim...

The 1400BP eruption of Rabaul erupted >11km3 of mainly crystal-poor dacitic magma, and lead to caldera collapse. Following an initial Plinian phase, multiple pyroclastic flows were then emplaced. In order to identify any pre-eruptive reservoir stratigraphy, we have sampled throughout the eruptive sequence: the Plinian fall deposit, the basal surge...

Large, explosive, caldera-forming eruptions are amongst the most destructive phenomena on the planet, but the processes that allow the large bodies of crystal-poor silicic magma that feed them to assemble in the shallow crust are still poorly understood. Of particular interest is the timescales over which these reservoirs exist prior to eruption. L...

The formation of shallow, caldera-sized reservoirs of crystal-poor silicic magma requires the generation of large volumes of silicic melt, followed by the segregation of that melt and its accumulation in the upper crust. The 21.8 ± 0.4-ka Cape Riva eruption of Santorini discharged >10 km3 of crystal-poor dacitic magma, along with 3 of hybrid andesi...

Large caldera-forming eruptions are commonly preceded by effusive eruptions whose magma chemically and petrologically resembles that of the climatic eruption. Studying these lavas can reveal processes that occur in the build-up to these often-catastrophic eruptions. On Santorini, the 21.7±0.2 ka caldera-forming Cape Riva eruption produced at least...

Caldera-forming eruptions are amongst the most destructive phenomena on this planet. Constraining the processes that occur before these eruptions, as well as the timescales of those processes, is vital for forecasting the behaviour of the volcanoes responsible for them. The 21.7 \ensuremath{\pm}0.2~ka caldera-forming Cape Riva eruption of Santorini...

The Cape Riva eruption of Santorini Volcano discharged several km3 of dacitic magma about 22,000 years ago. This eruption was preceded by the extrusion of lava domes and flows (the Therasia dome complex), which have a similar major element composition. The Therasia lavas are interpreted as leaks from the Cape Riva magma body as it was assembled and...

We present the results of the first systematic study of melt compos-itions at Pantelleria, based on both melt inclusions and matrix glasses in pantellerites from 10 eruptions during the last eruptive cycle (5 45 kyr). We present major and trace element compositions, as well as data on the volatiles sulphur (S), fluorine (F), chlorine (Cl), water (H...