Articles | Volume 16, issue 6
https://doi.org/10.5194/se-16-551-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/se-16-551-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
30 Jun 2025
Research article |
| 30 Jun 2025
| 30 Jun 2025
Time changes during the last 40 years in the Solfatara magmatic–hydrothermal system (Campi Flegrei, Italy): new conceptual model and future scenarios
Luigi Marini
STEAM srl, Pisa, 56124, Italy
CNR, Istituto di Geoscienze e Georisorse, Pisa, 56124, Italy
Claudia Principe
CNR, Istituto di Geoscienze e Georisorse, Pisa, 56124, Italy
INGV – Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Vesuviano, Napoli, 80124, Italy
CNR, Istituto di Geoscienze e Georisorse, Pisa, 56124, Italy
INGV – Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Pisa, Pisa, 56125, Italy
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Cécile Massiot, Ludmila Adam, Eric S. Boyd, S. Craig Cary, Daniel R. Colman, Alysia Cox, Ery Hughes, Geoff Kilgour, Matteo Lelli, Domenico Liotta, Karen G. Lloyd, Tiipene Marr, David D. McNamara, Sarah D. Milicich, Craig A. Miller, Santanu Misra, Alexander R. L. Nichols, Simona Pierdominici, Shane M. Rooyakkers, Douglas R. Schmitt, Andri Stefansson, John Stix, Matthew B. Stott, Camille Thomas, Pilar Villamor, Pujun Wang, Sadiq J. Zarrouk, and the CALDERA workshop participants
Sci. Dril., 33, 67–88, https://doi.org/10.5194/sd-33-67-2024, https://doi.org/10.5194/sd-33-67-2024, 2024
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Volcanoes where tectonic plates drift apart pose eruption and earthquake hazards. Underground waters are difficult to track. Underground microbial life is probably plentiful but unexplored. Scientists discussed the idea of drilling two boreholes in the Okataina Volcanic Centre, New Zealand, to unravel the connections between volcano, faults, geotherms, and the biosphere, also integrating mātauranga Māori (Indigenous knowledge) to assess hazards and manage resources and microbial ecosystems.
Related subject area
Subject area: Crustal structure and composition | Editorial team: Geochemistry, mineralogy, petrology, and volcanology | Discipline: Geochemistry
Evolution of fluid redox in a fault zone of the Pic de Port Vieux thrust in the Pyrenees Axial Zone (Spain)
Mapping geochemical anomalies by accounting for the uncertainty of mineralization-related elemental associations
Rare Earth element distribution on the Fuerteventura Basal Complex (Canary Islands, Spain): a geochemical and mineralogical approach
Mineralogical and elemental geochemical characteristics of Taodonggou Group mudstone in the Taibei Sag, Turpan–Hami Basin: implication for its formation mechanism
Application of lithogeochemical and pyrite trace element data for the determination of vectors to ore in the Raja Au–Co prospect, northern Finland
Influence of basement rocks on fluid evolution during multiphase deformation: the example of the Estamariu thrust in the Pyrenean Axial Zone
Spatiotemporal history of fault–fluid interaction in the Hurricane fault, western USA
Fluid–rock interactions in the shallow Mariana forearc: carbon cycling and redox conditions
Squirt flow due to interfacial water films in hydrate bearing sediments
Delphine Charpentier, Gaétan Milesi, Pierre Labaume, Ahmed Abd Elmola, Martine Buatier, Pierre Lanari, and Manuel Muñoz
Solid Earth, 15, 1065–1086, https://doi.org/10.5194/se-15-1065-2024, https://doi.org/10.5194/se-15-1065-2024, 2024
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Understanding the fluid circulation in fault zones is essential to characterize the thermochemical evolution of hydrothermal systems in mountain ranges. The study focused on a paleo-system of the Pyrenees. Phyllosilicates permit us to constrain the evolution of temperature and redox of fluids at the scale of the fault system. A scenario is proposed and involves the circulation of a single highly reducing hydrothermal fluid (~300 °C) that evolves due to redox reactions.
Jian Wang, Renguang Zuo, and Qinghai Liu
Solid Earth, 15, 731–746, https://doi.org/10.5194/se-15-731-2024, https://doi.org/10.5194/se-15-731-2024, 2024
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This study improves geochemical mapping by addressing the uncertainty in defining element associations. It clusters the study area by element similarity, recognizes elemental associations for each cluster, and then detects anomalies indicating underlying geological processes. This method is applied to a region in China, confirming its effectiveness and consistency with the geology. This study can enhance geochemical mapping for mineral exploration and improve geological-process understanding.
Marc Campeny, Inmaculada Menéndez, Luis Quevedo, Jorge Yepes, Ramón Casillas, Agustina Ahijado, Jorge Méndez-Ramos, and José Mangas
Solid Earth, 15, 639–656, https://doi.org/10.5194/se-15-639-2024, https://doi.org/10.5194/se-15-639-2024, 2024
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The Basal Complex unit on Fuerteventura island comprises magmatic rocks showing significant rare Earth element (REE) concentrations with values up to 10 300 ppm REY (REEs plus yttrium). We carried out mineralogical and geochemical analyses, but additional research is needed to fully understand their distribution due to structural complexities and environmental factors.
Huan Miao, Jianying Guo, Yanbin Wang, Zhenxue Jiang, Chengju Zhang, and Chuanming Li
Solid Earth, 14, 1031–1052, https://doi.org/10.5194/se-14-1031-2023, https://doi.org/10.5194/se-14-1031-2023, 2023
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The Taodonggou Group mudstone was deposited in a warm, humid, and hot paleoclimate with strong weathering. The parent rocks of the Taodonggou Group mudstone are felsic volcanic rocks and andesites, with weak sedimentary sorting and recycling and with well-preserved source information. The Taodonggou Group mudstone was deposited in dyoxic fresh water–brackish water in intermediate-depth or deep lakes with stable inputs of terrigenous debris but at slower deposition rates.
Sara Raič, Ferenc Molnár, Nick Cook, Hugh O'Brien, and Yann Lahaye
Solid Earth, 13, 271–299, https://doi.org/10.5194/se-13-271-2022, https://doi.org/10.5194/se-13-271-2022, 2022
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Orogenic gold deposits in Paleoproterozoic belts in northern Finland have been explored not only for gold but because of the occurrences of economically important concentrations of base metals, especially cobalt. In this study we are testing the vectoring capacities of pyrite trace element geochemistry, combined with lithogeochemical and sulfur isotopic data in the Raja gold–cobalt prospect (northern Finland), by using multivariate statistical data analysis.
Daniel Muñoz-López, Gemma Alías, David Cruset, Irene Cantarero, Cédric M. John, and Anna Travé
Solid Earth, 11, 2257–2281, https://doi.org/10.5194/se-11-2257-2020, https://doi.org/10.5194/se-11-2257-2020, 2020
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This study assesses the influence of basement rocks on the fluid chemistry during deformation in the Pyrenees and provides insights into the fluid regime in the NE part of the Iberian Peninsula.
Jace M. Koger and Dennis L. Newell
Solid Earth, 11, 1969–1985, https://doi.org/10.5194/se-11-1969-2020, https://doi.org/10.5194/se-11-1969-2020, 2020
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The Hurricane fault is a major and active normal fault located in the southwestern USA. This study utilizes the geochemistry and dating of calcite veins associated with the fault to characterize ancient groundwater flow. Results show that waters moving along the fault over the last 540 000 years were a mixture of infiltrating fresh water and deep, warm salty groundwater. The formation of calcite veins may be related to ancient earthquakes, and the fault influences regional groundwater flow.
Elmar Albers, Wolfgang Bach, Frieder Klein, Catriona D. Menzies, Friedrich Lucassen, and Damon A. H. Teagle
Solid Earth, 10, 907–930, https://doi.org/10.5194/se-10-907-2019, https://doi.org/10.5194/se-10-907-2019, 2019
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To understand the fate of carbon in subducted oceanic sediments and crust, we studied carbonate phases in rocks from the Mariana subduction zone. These show that carbon is liberated from the downgoing plate at depths less than 20 km. Some of the carbon is subsequently trapped in minerals and likely subducts to greater depths, whereas fluids carry the other part back into the ocean. Our findings imply that shallow subduction zone processes may play an important role in the deep carbon cycle.
Kathleen Sell, Beatriz Quintal, Michael Kersten, and Erik H. Saenger
Solid Earth, 9, 699–711, https://doi.org/10.5194/se-9-699-2018, https://doi.org/10.5194/se-9-699-2018, 2018
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Sediments containing hydrates dispersed in the pore space show a characteristic seismic anomaly: a high attenuation along with increasing seismic velocities. Recent major findings from synchrotron experiments revealed the systematic presence of thin water films between quartz and gas hydrate. Our numerical studies support earlier speculation that squirt flow causes high attenuation at seismic frequencies but are based on a conceptual model different to those previously considered.
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Short summary
We revised the conceptual model of the Solfatara magmatic–hydrothermal system and used new geothermometers and geobarometers, specifically calibrated for the Solfatara fluids, to monitor temperature, T, and total fluid pressure, P, in three distinct reservoirs at different depths, over ~40 years. The T and P changes in the intermediate reservoir (at 2.7–4 km depth) are of utmost interest because its pressurization–depressurization acts as the “engine” of bradyseism currently affecting the area.
We revised the conceptual model of the Solfatara magmatic–hydrothermal system and used new...
