A5056536911- Geological and Geochemical Analysis
- High-pressure geophysics and materials
- earthquake and tectonic studies
- Geology and Paleoclimatology Research
- Hydrocarbon exploration and reservoir analysis
- Geomagnetism and Paleomagnetism Studies
- CO2 Sequestration and Geologic Interactions
- Landslides and related hazards
- Geotechnical and Geomechanical Engineering
- Glass properties and applications
- Rock Mechanics and Modeling
- Geological and Tectonic Studies in Latin America
- Building materials and conservation
- Geological and Geophysical Studies
- Pickering emulsions and particle stabilization
- Seismic Waves and Analysis
- Geological Modeling and Analysis
- Mineralogy and Gemology Studies
- Geological formations and processes
- Climate variability and models
- Iron and Steelmaking Processes
- Earthquake Detection and Analysis
- Fluid Dynamics and Mixing
- Nanopore and Nanochannel Transport Studies
- Geotourism and Geoheritage Conservation
University of Liverpool
2014-2022
Liverpool Hospital
2018
EarthSky
2015
University of Canterbury
2013-2014
Ludwig-Maximilians-Universität München
2010-2011
Unoccupied aircraft systems (UAS) are developing into fundamental tools for tackling the grand challenges in volcanology; here, we review used and their diverse applications. UAS can typically provide image topographic data at two orders of magnitude better spatial resolution than space-based remote sensing, close-range observations temporal resolutions down to those video frame rates. Responsive deployments facilitate dense time-series measurements, unique opportunities geophysical surveys,...
Abstract Volcanic ash is often deposited in a hot state. containing glass, above the glass transition interval, has potential to sinter viscously both itself (particle‐particle) and exposed surfaces. Here we constrain kinetics of this process experimentally under nonisothermal conditions using standard glasses. In absence external load, dominantly driven by surface relaxation. such cases sintering rate limited melt viscosity, size particles melt‐vapor interfacial tension. We propose...
Columnar joints form by cracking during cooling-induced contraction of lava, allowing hydrothermal fluid circulation. A lack direct observations their formation has led to ambiguity about the temperature window jointing and its impact on flow. Here we develop a novel thermo-mechanical experiment disclose columnar in lavas. Using basalts from Eyjafjallajökull volcano (Iceland) show that cooling induces stress build-up below solidus (980 °C), resulting localised macroscopic failure between 890...
Abstract The highly transient nature of outgassing commonly observed at volcanoes is in part controlled by the permeability lava domes and shallow conduits. Lava generally consist a porous outer carapace surrounding denser core with internal shear zones variable porosity. Here we examine densification using uniaxial compression experiments on variably crystalline rhyolitic dome lavas from Taupo Volcanic Zone. Experiments were conducted 900°C an applied stress 3 MPa to 60% strain, while...
Sintering-or coalescence-of viscous droplets is an essential process in many natural and industrial scenarios. Current physical models of the dynamics sintering are limited by lack explicit account evolution microstructural geometry. Here, we use high-speed time-resolved x-ray tomography to image evolving geometry a system droplets, lattice Boltzmann simulations creeping fluid flow through reconstructed pore space determine its permeability. We identify characterize topological inversion,...
Volcanic ash and pyroclasts can weld when deposited hot by pyroclastic density currents, in near-vent fall deposits, or fractures volcano interiors. Welding progressively decreases the permeability of particle packs, influencing a range magmatic volcanic processes, including magma outgassing, which is an important control on eruption dynamics. Consequently, there need for quantitative model evolution during welding under conditions encountered nature. Here we present situ experiments...
Abstract The concluding episode of activity during the recent eruption Mt. Unzen (October 1994 to February 1995) was characterized by incremental spine extrusion, accompanied seismicity. Analysis seismic record reveals occurrence two dominant long‐period event families associated with a repeating, nondestructive source mechanism, which we attribute magma failure and fault‐controlled ascent. We obtain constraints on slip rate distance faulting events within these families. That analysis is...
Super-eruptions generating hundreds of cubic kilometres pyroclastic density currents are commonly recorded by thick, welded and lava-like ignimbrites. Despite the huge environmental impact inferred for this type eruption, little is yet known about timescales deposition post-depositional flow. Without these timescales, critical question duration any impact, ensuing gravity its effects Earth system, eludes us. The eruption welding ignimbrites requires three transects glass transition. Magma...
Abstract The rapid discharge of gas and rock fragments during volcanic eruptions generates acoustic infrasound. Here we present results from the inversion infrasound signals associated with small moderate gas‐and‐ash explosions at Santiaguito volcano, Guatemala, to retrieve time history mass eruption rate vent. Acoustic waveform is complemented by analyses thermal infrared imagery constrain volume rise dynamics plume. Finally, combine two methods in order assess bulk density erupted mixture,...
During magma ascent, bubbles nucleate, grow, coalesce, and form a variably permeable porous network. The volcanic system opens closes as bubble walls reorganize, seal or fail. In this contribution we cause obsidian to nucleate grow high gas volume fraction at atmospheric pressure by heating samples 950 ºC for different times image the growth through furnace. Following experiment, imaged internal pore structure of selected in 3D then dissected analysis textures dissolved water content remnant...
During explosive eruptions, a suspension of gas and pyroclasts rises rapidly within conduit. Here, we have analysed textures preserved in the walls pyroclastic feeder dyke AD 1886 Tarawera basaltic Plinian fissure eruption. The samples examined consist ash scoria plastered onto conduit wall coherent rhyolite dome welded rhyolitic breccia. We examine textural evidence for response material, built ∼75 vol.% glass ∼25 crystals (pore-free equivalent), to mass movement adjacent In quantify...
Facile route to polymer carbon nanotube nanocomposites.
The suitability of volcanic glass for paleointensity determinations is the basis many studies. dominant single domain (SD) magnetic remanence carriers, pristine character glass, and possibility to correct data cooling rate dependence using relaxation geospeedometry are all arguments that have been made in favor this technique. In present study validity correction tested remelted glass. To obtain a stable multicomponent with ideal properties, natural phonolitic from Tenerife was air avoid...
A comprehensive understanding of the dynamic evolution active volcanic systems requires extensive sets geophysical and geological data to fully constrain understand shifts in eruptive behavior. The Santiaguito dome complex, Guatemala, is a remarkable example an open-vent system where continuous activity has historically been characterized by cycles effusion frequent, small moderate, gas-and-ash explosions. During 2015-2016 volcano experienced rapid intensification including large vulcanian...
Protracted volcanic eruptions may exhibit unanticipated intensifications in explosive behaviour and attendant hazards. Santiaguito dome complex, Guatemala, has been characterised by century-long effusion interspersed with frequent, small-to-moderate (<2 km high plumes) gas-and-ash explosions. During 2015–2016, explosions intensified generating hazardous ash-rich plumes (up to 7 high) pyroclastic flows. Here, we integrate petrological, geochemical geophysical evidence evaluate the causes of...
Many of the grand challenges in volcanic and magmatic research are focused on understanding dynamics highly heterogeneous systems, critical conditions which enable magmas to move, or eruptions initiate. From formation development magma reservoirs, through propagation arrest magma, conduit, gas escape, eruption beyond into environmental impacts that eruption: we trying define how processes occur, their rates timings, causes consequences. However, usually unable observe directly. Here give a...
[1] A paleomagnetic study on phonolitic obsidian from six sites in Tenerife, Spain is presented. Two are located at the 750 ka El Pasajiron southern wall of Las Canadas Caldera. Four correspond to 115 ± 17 BCE Montana Blanca Complex. Paleointensity determinations performed with a modified Thellier technique using checks for alteration and domain state. Additionally, anisotropy thermoremanence magnetic cooling rate dependency each specimen measured. It was not possible obtain good quality...