Showing papers in "Journal of Volcanology and Geothermal Research in 2020"

TL;DR: In this article, the authors present a wealth of laboratory data and suggest tools, widely used in geotechnics but adapted here to better suit volcanic rocks, to upscale these values to the scale of a volcanic rock mass.

TL;DR: In this paper, the porosity and permeability of the main lithologies forming the reservoir, and the impacts of different thermal and mechanical stimulation practices to improve fluid flow, were investigated in Krafla Volcano, North-East Iceland.

TL;DR: In a two-year period 2015-2016, the most seismically active volcanoes were Katla and Barðarbunga as discussed by the authors, and the most active volcano swarm was Barðurbunga.

TL;DR: The role of hydrothermal alteration in the development of geothermal and epithermal mineral resources, systems that require the efficient hydthermal circulation provided by fracture networks, is investigated from a petrophysical standpoint using samples collected from a well exposed and variably altered palaeo-hydrothermal system hosted in the Ohakuri ignimbrite deposit in the Taupō Volcanic Zone (New Zealand).

TL;DR: In this article, the Hellisheidi geothermal power plant in south-west Iceland observed up to 2 cm of surface displacements during 2011-2012, indicating expansion of the crust.

TL;DR: The Iceland Deep Drilling Project (IDDP-2) as discussed by the authors was the first project to drill into supercritical geothermal systems and examine their economic potential, with a total loss of circulation below 3 km depth and continuing to the final depth.

TL;DR: The Reykjanes Peninsula is a trans-tensional plate boundary with several volcanic systems from the centers of which fissure swarms extend to the NE and SW as discussed by the authors.

TL;DR: In 2018, the La Soufriere volcano reached its highest seismic energy level with the largest felt volcano-tectonic (VT) earthquake (ML 4.1 or MW 3.7) recorded since the 1976-1977 phreatic eruptive crisis as mentioned in this paper.

TL;DR: An interdisciplinary approach is presented that combines stakeholder requirements with fundamental science to produce multi-hazard eruption scenarios for a high-risk volcano and applies this approach to the Auckland Volcanic Field to develop a suite of scenarios (‘DEVORA Scenarios’) that cover the wide spectrum of credible expected eruption activity.

TL;DR: In this paper, the authors analyzed unrest signals recorded in one of the largest monogenetic fields in the Canary Islands, Cumbre Vieja (La Palma), registering b-values of 1.6 and 2.3 respectively suggesting an intense magmatic fluids contribution, gas and/or magma.

TL;DR: In this paper, a large seismic network deployed in the Icelandic highlands recorded >100,000 earthquakes from 2009 to 2015, and the authors developed a local magnitude scale, appropriate for use in central Iceland, which is similar to the scale used by the Iceland Meteorological Office.

TL;DR: In this paper, the authors studied the Reykjanes Peninsula oblique rift and found evidence for at least six strike-slip faults with an over-all trend of 70°, highly oblique with respect to the spreading direction.

TL;DR: The Masaya Triple Layer tephra was deposited ~2100-years ago during a basaltic Plinian eruption of Masaya caldera, Nicaragua, and is one of few known examples of this extreme endmember of basaltitic explosive volcanism as mentioned in this paper.

TL;DR: The Generalized Millennium Eruption (GME) was proposed in this paper to avoid entrenched confusion and to formally acknowledge the composite comendite-trachyte nature of the eruption.

TL;DR: In this paper, the authors demonstrate the use of remote infrasound in estimating the height of volcanic plumes, including a case study on the May 30, 2014 plume from the volcano Sangeang Api in Indonesia.

TL;DR: In this article, the authors investigated the hydrogeochemistry of geothermal waters from 31 geothermal fields in eastern Turkey with regard to major ion compositions, stable (δ18O-δ2H- δ34S) and tritium (3H) isotope systematics.

TL;DR: In this article, the heat source of the Northwest Geysers using newly collected gravity and magnetotelluric (MT) measurements was estimated using existing geologic cross-section.

TL;DR: In this paper, the authors provide laboratory measurements of thermal conductivity and thermal diffusivity for variably porous andesites from Mt. Ruapehu (New Zealand) and variably altered basaltic-andesite from Merapi volcano (Indonesia) measured at ambient laboratory pressure and temperature using the transient hotstrip method.

TL;DR: TanDEM-X DEM on Fuego volcano (Guatemala) was used to measure the significant topographic changes caused by the 3rd June 2018 eruption, which destroyed the town of San Miguel Los Lotes as discussed by the authors.

TL;DR: In this paper, a water-in-olivine chronometer was used to estimate the syneruptive decompression rate of basaltic magma in volcanic conduits.

TL;DR: In this article, the authors study dyke paths resulting in eruption or arrest in an excellent 5 km wide exposure of the northern caldera wall of the Santorini volcano in Greece.

TL;DR: In this article, the authors estimate the CO2 released from Furnas do Enxofre degassing area (Terceira Island, Azores archipelago) by applying an approach that integrates the flux of CO2 from the soil with the δ13C-CO2 values.

TL;DR: In this paper, the authors conducted extensive and regular spaced soil gas surveys within the Los Humeros geothermal field to improve the understanding of the structural control on fluid flow, and identified five areas with increased CO2 emissions, where further sampling was performed with denser sampling grids to understand the fault zone architecture and local variations in gas emissions.

TL;DR: In this paper, the authors describe the electrical resistivity structure around Mt. Motoshirane down to a depth of ~10 km using broadband magnetotelluric (MT) data (320-0.0005 ) collected in 2015 and 2016.

TL;DR: The International Volcanic Health Hazard Network (www.ivhhn.org ) organized a two-day workshop to define appropriate methods for hazard assessment as discussed by the authors, which was subsequently ratified by leading volcanological organizations.

TL;DR: In this paper, a 3D inversion was performed of the static shift corrected off-diagonal impedance tensor elements of 102 MagnetoTelluric (MT) resistivity soundings from the Greater Krýsuvik geothermal area.

TL;DR: In this paper, the authors present the results of an integrated study (structural, kinematic, fluid inclusions analyses) carried out on a fossil and exhumed geothermal system at Geitafell (SE Iceland), considered an analogue of the active Krafla geothermal systems (NE Iceland).

TL;DR: In this article, the authors studied the role of large tectonic features in fluid transport and magma ascent processes in the Southern Volcanic Zone of the Andes of Chile, such as the Liquine-Ofqui Fault Zone, a strike-slip crustal structure parallel to the main volcanic arc.

TL;DR: In this article, the authors deal mainly with acidic sulphate-chloride (ASC) waters that are discharged at volcanic edifices, generally, not associated with crater lakes, and assess the nature of such waters using their chemical and isotopic composition.

TL;DR: The average volcanic plume chemistry is characterised by a mean molar CO2/SO2 ratio of 2.14, H2O/SO 2 of 148 and SO2/HCl of 1.02.