Volcanic Systems and Hydrothermal Processes

Volcanic systems consist of interconnected magmatic and hydrothermal networks that transport heat, fluids and gases from the deep crust to the surface. Magma chambers feed conduits through which melts ascend, fragment and release volatiles, while circulating groundwater forms hydrothermal cells driven by heat flux and phase separation. Interaction between magmatic intrusions and overlying aquifers generates mineral-rich fluids, surface manifestations such as fumaroles, hot springs and altered rock assemblages, and can culminate in phreatic or phreatomagmatic eruptions. These processes are central to volcanic hazard assessment, geothermal energy exploration and biogeochemical cycling in crustal environments. Understanding the coupling between magma dynamics, fluid flow and rock alteration is essential to forecast unrest, manage resource exploitation and mitigate risks globally.

Research from Nature Portfolio

Recent studies have employed three-dimensional magnetotelluric surveys to reveal resistivity contrasts beneath La Fossa caldera, identifying conduit-like structures for magmatic fluid ascent and conductive anomalies denoting shallow hydrothermal reservoirs. Further geochemical investigations at Vulcano Island have demonstrated that pulses of volatile-rich mafic magma at mid-crustal depths drive phases of intensified sulphur dioxide flux, underlining magma–hydrothermal interplay as a fundamental mechanism for unrest. Complementary work quantifying soil CO₂ emissions during the 2021–2022 degassing crisis has linked deep volatile input to pressure variations within the shallow plumbing system, providing critical benchmarks for real-time monitoring and early warning strategies.

Research from all publishers

Field and geochemical analyses on Lipari Island have characterised advanced argillic alteration assemblages, confirming that steam condensation alone can generate silica- and sulphate-rich minerals without requiring magmatic halogen input. Multi-temporal interferometric SAR and GNSS observations at La Fossa caldera have documented elliptical uplift patterns consistent with hydrothermal pressurisation, while seismic networks recorded very long period events indicative of fluid injection into fracture networks. A multidisciplinary surveillance network integrating geodetic, soil-gas flux, gas geochemistry and thermal datasets has demonstrated the power of combining physical and chemical observables to resolve sequential phases of unrest and refine hazard interpretation frameworks.

Volcanic Systems and Hydrothermal Processes publication trend

The graph below shows the total number of articles in volcanic systems and hydrothermal processes across all publications each year (not limited to Nature Index journals).

Technical terms

Caldera: A large, basin-shaped depression formed by volcanic collapse or explosive eruption.

Conduit: A channel through which magma and hydrothermal fluids ascend towards the surface.

Magnetotellurics: A geophysical method measuring natural electromagnetic fields to image subsurface resistivity variations.

Very long period (VLP) events: Low-frequency seismic signals often linked to slow fluid movement in volcanic systems.

Argillic alteration: Hydrothermal alteration producing clay minerals such as kaolinite and montmorillonite under acidic conditions.

References

1. Three-dimensional magnetotelluric modeling of Vulcano Island (Eolie, Italy) and its implications for understanding recent volcanic unrest. Scientific Reports (2023).
2. Mafic magma feeds degassing unrest at Vulcano Island, Italy. Communications Earth & Environment (2022).
3. The volcanic activity changes occurred in the 2021–2022 at Vulcano island (Italy), inferred by the abrupt variations of soil CO2 output. Scientific Reports (2022).
4. Advanced argillic alteration at Cave di Caolino, Lipari, Aeolian Islands (Italy): Implications for the mitigation of volcanic risks and the exploitation of geothermal resources. The Science of The Total Environment (2023).
5. Multi‐Temporal InSAR, GNSS and Seismic Measurements Reveal the Origin of the 2021 Vulcano Island (Italy) Unrest. Geophysical Research Letters (2023).
6. Inferences on the 2021 Ongoing Volcanic Unrest at Vulcano Island (Italy) through a Comprehensive Multidisciplinary Surveillance Network. Remote Sensing (2023).