Preprints
Filtering by Subject: Volcanology
Structural controls on the emplacement and evacuation of magma from a sub-volcanic laccolith; Reyðarártindur Laccolith, SE Iceland
Published: 2021-01-06
Subjects: Earth Sciences, Geology, Higher Education, Physical Sciences and Mathematics, Science and Mathematics Education, Tectonics and Structure, Volcanology
VESIcal Part I: An open-source thermodynamic model engine for mixed volatile (H2O-CO2) solubility in silicate melts
Published: 2020-12-08
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics, Planetary Geochemistry, Planetary Geology, Planetary Sciences, Volcanology
Thermodynamics has been fundamental to the interpretation of geologic data and modeling of geologic systems for decades. However, more recent advancements in computational capabilities and a marked increase in researchers’ accessibility to computing tools has outpaced the functionality and extensibility of currently available modeling tools. Here we present VESIcal (Volatile Equilibria and [...]
The shape of volcanic conduits inferred from bubble size distributions
Published: 2020-11-28
Subjects: Earth Sciences, Volcanology
The most intense known explosive volcanic eruptions on Earth are Plinian eruptions of silicic magma. Geospeedometers indicate that Plinian magma erupts from high pressure within the magma chamber at average speeds of 0.001-1 MPa/s. Concurrently dissolved magmatic volatiles, predominantly water, nucleate about one quadrillion bubbles per cubic meter of melt, preserved as vesicles within tephra. [...]
Boron isotopic signatures of melt inclusions from North Iceland reveal recycled material in the Icelandic mantle source
Published: 2020-11-13
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics, Volcanology
Trace element and volatile heterogeneity in the Earth's mantle is in uenced by the recycling of oceanic lithosphere through subduction. Oceanic island basalts commonly have high concentrations of volatiles compared to mid-ocean ridge basalts, but the extent to which this enrichment is linked to recycled mantle domains remains unclear. Boron is an ideal tracer of recycled subducted material, [...]
Segment tip geometry of sheet intrusions, II: Field observations of tip geometries and a model for evolving emplacement mechanisms
Published: 2020-11-03
Subjects: Earth Sciences, Geology, Volcanology
Igneous sheet intrusions are segmented across several orders of magnitude, with segment tip geometry commonly considered indicative of the propagation mechanism (brittle or non-brittle). Proposed propagation mechanisms are inferred to represent host rock mechanical properties during initial magma emplacement; typically, these models do not account for segment sets that show a range of tip [...]
Studying the initiation of volcanic eruptions: Time for a petrological perspective.
Published: 2020-10-28
Subjects: Earth Sciences, Volcanology
Volcano monitoring is essential for mitigating the risks associated with volcanic activity. As monitoring becomes more sophisticated and widespread, there is a growing need for understanding the relationship between different monitoring records and magmatic processes occurring at depth. This is particularly relevant to the processes that initiate eruptions after the extended periods of repose and [...]
Salt-magma interactions influence intrusion distribution and salt tectonics in the Santos Basin, offshore Brazil
Published: 2020-10-25
Subjects: Earth Sciences, Geology, Tectonics and Structure, Volcanology
Many sedimentary basins host thick evaporite (salt) deposits. Some of these basins also host extensive igneous intrusion networks. It thus seems inevitable that, in some locations, magma will interact with salt. Yet how interaction between these materials may influence salt tectonics or magma emplacement, particularly at the basin-scale, remains poorly understood. We use 3D seismic reflection [...]
Was the Kalkarindji continental flood basalt province a driver of environmental change at the dawn of the Phanerozoic?
Published: 2020-10-22
Subjects: Paleobiology, Volcanology
The Kalkarindji continental flood basalt province of Northern Australia is the oldest basaltic LIP in the Phanerozoic having erupted in the mid Cambrian. At this time, during the Cambrian Explosion, the global environment suffered a series of mass extinctions and biotic turnover. Kalkarindji had the potential to release 1.65 x 106 Tg of CO2, approximately 1.72% of the total Cambrian atmospheric [...]
Amphibole Control on Copper Systematics in Arcs: Insights from the Analysis of Global Datasets
Published: 2020-10-21
Subjects: Earth Sciences, Geochemistry, Geology, Volcanology
Copper, sourced from porphyry deposits formed in arc settings, is a critical resource, and is primarily sourced from magmas. However, the processes that shape the copper contents of arc magmas are up for debate. Existing models place emphasis on different petrological agents that explain large-scale trends in copper systematics. Previous studies have noted the 'Cu paradox,' where the magmas with [...]
The Volcanic & Magmatic Studies Group Equality, Diversity and Inclusion Report 2020
Published: 2020-07-24
Subjects: Earth Sciences, Education, Physical Sciences and Mathematics, Volcanology
The Volcanic and Magmatic Studies Group (VMSG) takes equality, diversity and inclusion (EDI) seriously and we recognise that the under-representation and/or unconscious marginalisation of any group impacts on our ability to fulfill our mission to serve the volcanology, petrology and geochemistry community. The following report summarises the findings from both the 2016-2020 VMSG annual meetings [...]
Volcanic and Magmatic Studies Group Members Survey 2020
Published: 2020-07-24
Subjects: Earth Sciences, Physical Sciences and Mathematics, Volcanology
The Volcanic & Magmatic Studies Group (VMSG) is a joint Special Interest Group of the Geological Society of London and Mineralogical Society. In January 2020 we conducted an online questionnaire to establish if (and how) VMSG fulfils its mission to serve the volcanology, petrology and geochemistry community. The survey was distributed via the VMSG mailing list, publicised at the VMSG annual [...]
Rapid heat discharge during deep-sea eruptions generates megaplumes and disperses tephra
Published: 2020-07-16
Subjects: Earth Sciences, Fluid Dynamics, Geology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Other Physical Sciences and Mathematics, Physical Sciences and Mathematics, Physics, Volcanology
Deep-marine volcanism drives Earth’s most energetic transfers of heat and mass between the crust and the oceans. Seafloor magmatic activity has been correlated in time with the appearance of massive enigmatic plumes of hydrothermal fluid, known as megaplumes, yet little is known of the primary source and intensity of the hydrothermal energy release that occurs during [...]
Turbulent flow effects in a slickwater fracture propagation in permeable rock
Published: 2020-06-18
Subjects: Earth Sciences, Environmental Sciences, Hydrology, Oil, Gas, and Energy, Physical Sciences and Mathematics, Volcanology
This work is devoted to an analysis of the near-tip region of a hydraulic fracture driven by slickwater in a permeable saturated rock. We consider a steady-state problem of a semi-infinite fracture propagating with constant velocity. The host rock is elastic and homogeneous, and fracture propagates according to linear elastic fracture mechanics. The fluid exchange between the fracture and [...]
Deformation controlled Long-Period seismicity in low cohesion volcanic sediments
Published: 2020-06-18
Subjects: Earth Sciences, Physical Sciences and Mathematics, Volcanology
Volcano seismicity is an important tool in remotely monitoring and forecasting activity at volcanoes around the world. Volcanic earthquakes show diverse spectral characteristics, with shallow Long Period (Low Frequency) seismicity and long duration tremor generally interpreted as indicators of fluid migration, and as potential precursors to eruption. Here we show that a common low-cohesion [...]
Heat does not physically flow in the ways assumed by greenhouse-warming theory
Published: 2020-06-06
Subjects: Climate, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Volcanology
Heat is currently defined as an amount of thermal energy flowing each second per unit area. Temperature is assumed to result from the net amount of heat flowing—the sum of all radiative forcings. Yet direct and unambiguous observations of Nature show that macroscopic temperature of solid matter results from a very broad spectrum of sub-microscopic oscillations of all the bonds holding matter [...]