Preprints
Filtering by Subject: Volcanology
Mapping the interaction of a pyroclastic density current with irregular topography: the chemically-zoned, low aspect-ratio Green Tuff ignimbrite, Pantelleria, Italy
Published: 2026-03-05
Subjects: Volcanology
Pyroclastic density currents are known to have high mobility, overtopping topographic barriers great distances from source. However, how density currents interact with topography is not yet fully understood, particularly with regard to dense, granular, sustained currents. We used detailed chemical mapping to show how the response of an individual pyroclastic current to topographic barriers [...]
Seismic Efficiency during Volcanic Unrest: Insights from the 2010 Eyjafjallajökull Eruption
Published: 2026-02-24
Subjects: Earth Sciences, Geophysics and Seismology, Volcanology
Identifying patterns in precursory signals may aid forecasting over month to year timescales. Here we examine the relationship between seismicity and ground deformation during unrest prior to the 2010 Eyjafjallajökull eruption. We find that the ratio between seismic moment and horizontal GPS ground displacement is constant within two distinct phases, but with a step increase from one to the [...]
Mid-crustal Origin of Alkaline Magmas in the Arosa Zone: Evidence from Primary Analcime and Xenolith Interaction at the Rothplattenbach Complex (Germany)
Published: 2026-02-14
Subjects: Geochemistry, Geology, Mineral Physics, Physical Sciences and Mathematics, Volcanology
The petrogenetic evolution of the alkaline magmatic rocks of the Rothplattenbach Complex was investigated by X-ray diffraction phase analysis and crystallographic lattice-parameter determination. The study focuses on the identification of primary analcime occurring in paragenesis with Ca-rich plagioclase (An₇₇) and diopsidic clinopyroxene. Phase-equilibrium modelling indicates that magma [...]
Magmatic volatile budgets of the 2014 Tavurvur eruption at Rabaul Caldera, Papua New Guinea
Published: 2026-01-31
Subjects: Earth Sciences, Geochemistry, Volcanology
Rabaul is a caldera volcano on New Britain Island, Papua New Guinea, whose active cone Tavurvur ranks seventh globally for long-term SO2 and CO2 emissions. It is unknown why Rabaul is such a strong emitter of volcanic gases. Magma mixing between basaltic and dacitic magmas is envisioned to play a fundamental role in driving eruptions at Rabaul, but the compositions of mafic recharge magmas and [...]
Analyzing volcanic-like earthquakes with distributed acoustic sensing using a short segment of the Tongan seafloor telecommunications cable
Published: 2026-01-30
Subjects: Volcanology
The 2022 Hunga Tonga-Hunga Haʻapai (HTHH) eruption highlighted the need for monitoring submarine volcanoes. Distributed Acoustic Sensing (DAS), utilizing existing seafloor cables offers a promising solution. We analyze a one-week DAS dataset recorded in February 2023, one year after the eruption, using a 30-km segment of the domestic telecommunication cable in Tonga. The previous study (Nakano et [...]
Petrological insights into magma storage and evolution at Rabaul Caldera, Papua New Guinea
Published: 2026-01-21
Subjects: Earth Sciences, Geochemistry, Volcanology
Rabaul is a caldera volcano in Papua New Guinea. Its most recent caldera-forming eruption occurred ~1400 years ago, with numerous intra-caldera eruptions since. Erupted whole rock compositions are commonly attributed to fractional crystallisation along a single liquid line of descent, but mafic mineral clots indicate mafic recharge and magma mixing also influence whole rock compositions. [...]
Solubility and speciation of sulfur in silicate melts under crustal conditions
Published: 2025-12-13
Subjects: Earth Sciences, Geochemistry, Geology, Volcanology
We have determined the solubility of sulfur as either sulfide (S2-) or sulfate (S6+) in a wide range of silicate melts at 1 atm pressure and temperatures of 1050° to 1250°C. The method involved suspension of the melt in either a mixture of CO2-CO-SO2 (sulfide solubility) or SO2 and air (sulfate solubility) for periods of up to 120 hours. Sulfur concentrations, measured by electron microprobe were [...]
Recurrent evacuation of mantle mush by mafic recharge in ocean island basalts, recorded by La Palma clinopyroxene
Published: 2025-12-04
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics, Volcanology
Temporal variations in magma plumbing architecture and magmatic processes influence eruption priming and the interpretation of pre- and syn-eruptive signals. Yet, how these processes operate in low-flux volcanoes remains poorly constrained, leaving a key gap in understanding eruption precursors. Here we examine the temporal evolution of magmatic processes at La Palma, Canary Islands, a low-flux [...]
Oxidation state of Mayotte magmatic series: insights from Fe and S K-edge XANES spectroscopy
Published: 2025-11-28
Subjects: Earth Sciences, Geochemistry, Volcanology
Following the 2018-2020 Fani Maoré submarine eruption near Mayotte Island, Indian Ocean, multiple oceanographic expeditions provide unprecedented access to fresh alkaline volcanic glasses spanning basanite to phonolite compositions from the East-Mayotte Volcanic Chain (EMVC). We applied Fe and S K-edge X-ray Absorption Near-Edge Spectroscopy (XANES) to determine iron and sulfur oxidation states [...]
Practical guide for volcano observatories on paleomagnetic sampling of pyroclastic deposits from active volcanoes
Published: 2025-11-15
Subjects: Geophysics and Seismology, Volcanology
This brief guide is designed to teach workers at observatories of volcanoes exhibiting explosive activity how to take samples of pyroclastic deposits for paleomagnetic studies. Paleomagnetism is a powerful tool for studying volcanoes, both dormant and currently active. Studies of the rock magnetic and paleomagnetic characteristics of volcanic rocks can provide important information about volcanic [...]
Modelling the transport and dispersion of volcanic co-PDC ash clouds using NAME: an evaluation of source geometry and mass eruption rate
Published: 2025-11-03
Subjects: Earth Sciences, Physical Sciences and Mathematics, Volcanology
Pyroclastic density currents (PDCs) are gravity currents that frequently form during explosive volcanic eruptions. These ground-hugging density currents consist of high-temperature mixtures of pyroclasts (e.g., ash, pumice), lithics, and gas. They have the potential to generate co-PDC plumes, which detach from the underlying PDC as they buoyantly rise into the atmosphere. Co-PDC plumes, composed [...]
Anomaly detection of Synthetic Aperture Radar Interferograms with semi-supervised machine learning
Published: 2025-11-01
Subjects: Geophysics and Seismology, Volcanology
The aim of this research is to detect Earth's deformation from Interferometric Synthetic Aperture Radar (InSAR) images through a semi-supervised machine learning algorithm called Least-Squares Two-sample Test (LSTT). This algorithm computes the probability distributions of two samples to assess if they belong to the same probability distribution. At the same time, it gives the divergence of these [...]
Assessing Volcanic Hazards and Financial Exposure: A Closer Look at Insurance Industry Preparedness
Published: 2025-10-22
Subjects: Earth Sciences, Environmental Sciences, Volcanology
Within the insurance and reinsurance sectors, volcanoes and their secondary impacts are often an overlooked risk due to the long return periods associated with large explosive eruptions, and relatively low economic and insured losses from eruption events compared to other natural hazards such as large magnitude earthquakes. However, with continued population growth, globalisation and climate [...]
Eocene lacustrine–volcaniclastic deposits at Aliabad (Central Iran): A possible Proto-basin of the Oligo-Miocene Qom Formation
Published: 2025-10-14
Subjects: Earth Sciences, Geology, Paleobiology, Paleontology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy, Volcanology
Central Iran hosts intricate Cenozoic successions where the Oligo‑Miocene Qom Formation forms a major hydrocarbon reservoir. The stratigraphic and paleoenvironmental relationship of the Eocene Aliabad deposits to this formation has been controversial. This study integrates stratigraphic logging, petrography, geochemistry (XRD/XRF), and ichnology on 46 thin sections from Aliabad and 157 [...]
Hunga eruption on 15 January 2022: Was there a precursor plume one hour before the eruption?
Published: 2025-09-04
Subjects: Atmospheric Sciences, Volcanology
This note is aimed at the examination of a precursor plume one hour before the paroxysmal Hunga eruption on 15 January 2022, following a claim made in Van Eaton et al. (2023). After examination of a number of satellite and meteorological data, it is concluded in agreement with Prata et al. (2024) that this claim results from a misinterpretation of satellite imagery.