Abstract The ingestion of volcanic ash by jet engines is widely recognized as a potentially fatal hazard for aircraft operation. high temperatures (1,200–2,000 °C) typical exacerbate the impact provoking its melting and sticking to turbine parts. Estimation this potential complicated fact that chemical composition, which affects temperature at becomes liquid, can vary amongst volcanoes. Here, based on experiments, we parameterize behaviour develop model predict conditions global...

[1] Magmas in volcanic conduits commonly contain microlites association with preexisting phenocrysts, as often indicated by rock textures. In this study, we present two different experiments that investigate the flow behavior of these bidisperse systems. first experiments, rotational rheometric methods are used to determine rheology monodisperse and polydisperse suspensions consisting smaller, prolate particles (microlites) larger, equant (phenocrysts) a bubble-free Newtonian liquid...

Explosive volcanic eruptions are defined as the violent ejection of gas and hot fragments from a vent in Earth's crust. Knowledge velocity is crucial for understanding modeling relevant physical processes an eruption, yet direct measurements still difficult task with largely variable results. Here we apply pioneering high‐speed imaging to measure pyroclasts Strombolian explosive unparalleled temporal resolution. Measured supersonic velocities, up 405 m/s, twice higher than previously...

Research Article| September 01, 2011 Aggregation-dominated ash settling from the Eyjafjallajökull volcanic cloud illuminated by field and laboratory high-speed imaging J. Taddeucci; Taddeucci 1Istituto Nazionale di Geofisica e Vulcanologia, Department of Seismology Tectonophysics, Via Vigna Murata 605, 00143, Rome, Italy Search for other works this author on: GSW Google Scholar P. Scarlato; Scarlato C. Montanaro; Montanaro 2Istituto Geologia Applicata Geoingegneria, CNR (Consiglio delle...

Explosive volcanic eruptions are commonly associated with intense electrical activity and lightning. Direct measurement of the electric potential at vent, where in plume is first observed, severely impeded, limiting progress its investigation. We have achieved lightning laboratory during rapid decompression experiments gas-particle mixtures under controlled conditions, recorded it using a high-speed camera two antennas. find that by dynamics particle-laden jet abundance fine particles. The...

Viscosity has been determined during isothermal crystallization of an andesite from Tungurahua volcano (Ecuador). was continuously recorded using the concentric cylinder method and employing a Pt-sheathed alumina spindle at 1 bar 1400°C to subliquidus temperatures track rheological changes crystallization. The disposable not extracted sample but rather left in quenching thus preserving undisturbed textural configuration crystals. inspection products quenched process reveals evidence for...

Abstract We recorded volcanic lightning generated by Vulcanian explosions at Sakurajima Volcano using a synchronized multiparametric array. Physical properties of are related to plume dynamics, and associated electromagnetic field variations revealed video observations (high speed normal speed) together with infrasound high sampling rate magnetotelluric signals. Data show that mainly occurs in the gas thrust region few hundred meters above crater rim, where overpressure turbulent jets...

Abstract Degassing dynamics play a crucial role in controlling the explosivity of magma at erupting volcanoes. magmatic water typically involves bubble nucleation and growth, which drive ascent. Crystals suspended may influence both growth bubbles. Micron- to centimeter-sized crystals can cause heterogeneous facilitate coalescence. Nanometer-scale crystalline phases, so-called “nanolites”, are an underreported phenomenon could exert primary control on eruptive style silicic Yet nanolites...

Abstract Volcanic activity occurring in tropical moist atmospheres can promote deep convection and trigger volcanic thunderstorms. These phenomena, however, are rarely observed to last continuously for more than a day so insights into the dynamics, microphysics electrification processes limited. Here we present multidisciplinary study on an extreme case, where volcanically-triggered lasted six days. We show that this unprecedented event was caused sustained by phreatomagmatic at Anak...

Research Article| May 01, 2010 Basaltic scoria textures from a zoned conduit as precursors to violent Strombolian activity C. Cimarelli; Cimarelli 1Dipartimento Scienze Geologiche, Università Roma Tre, Largo S.L. Murialdo 1, 00146 Rome, Italy Search for other works by this author on: GSW Google Scholar F. Di Traglia; Traglia 2Dipartimento della Terra, di Pisa, Via S. Maria 53, 56126 J. Taddeucci 3Istituto Nazionale Geofisica e Vulcanologia, Vigna Murata 605, 00143 Author and Article...

The fusion dynamics of volcanic ash strongly impacts deposition in hot parts jet engines. In this study, we investigate the sintering behavior using natural intermediate composition, erupted 2012 at Santiaguito Volcano, Guatemala. A material science procedure was followed which monitored geometrical evolution cylindrical-shaped compact upon heating from 50 to 1400°C a microscope. Combined morphological, mineralogical, and rheological analyses helped define during constrain their sticking...

The 2010 eruption of Eyjafjallajökull (Iceland) and the 2011 eruptions Grimsvötn (Iceland), Cordon Caulle (Chile) Nabro (Ethiopia) have drastically heightened level awareness in general population how volcanic activity can affect everyday life by disrupting air travel. ingestion airborne matter into jet turbines may cause harm (1) abrasion engine parts, (2) destabilisation fuel/air mix its dynamics (3) melting sintering ash onto parts. To investigate behaviour upon reheating, we performed...

Transport properties of natural silicate melts at super-liquidus temperatures are reasonably well understood. However, migration and transport in the Earth’s crust its surface generally occur sub-liquidus settings where undergo crystallization under various cooling and/or decompression conditions. In such dynamic situations occurrence processes as release latent heat during phase changes, viscous heating, thermal advection -inertia, changing capacity, all represent potential influences on...

Abstract Surtseyan eruptions are shallow to emergent subaqueous explosive that owe much of their characteristic behavior the interaction magma with water. The difference in thermal properties between water and air affects cooling postfragmentation vesiculation processes erupted into column. Here we study during 2009 2014–2015 Hunga Tonga‐Hunga Ha'apai volcano by combining 2‐D 3‐D vesicle‐scale analyses lapilli bombs numerical modeling. Most show gradual textural variations from rim core....

The lightning generated by explosive volcanic eruptions is of interest not only as a promising technique for monitoring activity, but also its broader implications and possible role in the origin life on Earth, impact atmosphere biosphere planet. However, at present genetic mechanisms physical properties remain poorly understood, compared to our understanding thundercloud lightning. Here, we joint magnetotelluric (MT) data video imagery that were used investigate electrical discharges during...

Abstract Volcanic lightning studies have revealed that there is a relatively long‐lasting source of very high frequency radiation associated with the onset explosive volcanic eruptions distinct from produced by lightning. This signal referred to as “continual radio (CRF)” due its nature. The discharge mechanism producing this was previously hypothesized be caused numerous, small (10–100 m) leader‐forming discharges near vent volcano. To test hypothesis, multiparametric data set electrical...

Volcanic ash can trigger ice nucleation when immersed in supercooled water. This will impact several processes (e.g., electrification, aggregation, precipitation) the eruption plume and cloud wider atmosphere upon dispersal. Previous studies show that bulk properties, reflecting chemistry phase state of source magma, likely contribute to ice-nucleating activity (INA) ash. However, it remains unexplored how interaction with magmatic gases hot plume, which inevitably leads altered surface...

The electrification of volcanic plumes has been described intermittently since at least the time Pliny Younger and 79 AD eruption Vesuvius. Although sometimes disregarded in past as secondary effects, recent work suggests that electrical properties reveal intrinsic otherwise inaccessible parameters explosive eruptions. An increasing number lightning studies across last decade have shown is ubiquitous plumes. Technological advances engineering numerical modelling, paired with close...