Magma accumulation and inflation mechanisms at Fernandina volcano, Galapagos Islands

Volcanism involving molten rock ('magma') with a low silica content ('basalt') is a fundamental component of the Earth system, critical to continental break-up, formation of new oceanic crust, and the growth of ocean islands. Basaltic volcanism also poses a significant hazard to those living near such volcanoes, destroying property, infrastructure, and livelihoods through lava flows, tephra fall, and gas emissions. The timing, size, style, and location of such eruptions is determined by the ascent, storage, and migration of magma, which take place under the ground, hidden from direct observation. Consequently, much of our understanding relies on measurements of small earthquakes and deformation of the Earth's surface caused by the movement of magma.

We will make new measurements of the earthquakes that result from the accumulation of magma at Fernandina, a large and very active volcano in the western Galápagos Islands, Ecuador. Since August 2022, the observation of earthquakes and uplift at Fernandina indicate that large volumes of magma are ascending to shallow levels in the volcano, potentially heralding a future eruption. However, the remote location of Fernandina means that the existing monitoring network is not able to record this activity with the resolution necessary to understand the key processes that are taking place. By urgently installing a dense network of modern seismometers, we will capture an important and novel dataset which will tell us about how the volcano accommodates the new magma and the internal structure and properties of the volcano. These data will underpin new approaches to modelling the behaviour of these systems, and ultimately to be better able to forecast future eruptions worldwide.