21 Result(s)

Article

Reported ultra-low lava viscosities from the 2021 La Palma eruption are potentially biased

Guillem Gisbert, Valentin R. Troll, James M. D. Day, Harri Geiger… in Nature Communications (2023)

Article

Hidden mechanical weaknesses within lava domes provided by buried high-porosity hydrothermal alteration zones

Catastrophic lava dome collapse is considered an unpredictable volcanic hazard because the physical properties, stress conditions, and internal structure of lava domes are not well understood and can change ra...

Herlan Darmawan, Valentin R. Troll, Thomas R. Walter… in Scientific Reports (2022)

Article

Sunda arc mantle source δ¹⁸O value revealed by intracrystal isotope analysis

Magma plumbing systems underlying subduction zone volcanoes extend from the mantle through the overlying crust and facilitate protracted fractional crystallisation, assimilation, and mixing, which frequently o...

Frances M. Deegan, Martin J. Whitehouse, Valentin R. Troll… in Nature Communications (2021)

Article

Constraining the sub-arc, parental magma composition for the giant Altiplano-Puna Volcanic Complex, northern Chile

The Andean continental arc is built upon the thickest crust on Earth, whose eruption products reflect varying degrees of crustal assimilation. In order to robustly model magma evolution and assimilation at sub...

Osvaldo González-Maurel, Frances M. Deegan, Petrus le Roux… in Scientific Reports (2020)

Article

Hydrothermal alteration of andesitic lava domes can lead to explosive volcanic behaviour

Dome-forming volcanoes are among the most hazardous volcanoes on Earth. Magmatic outgassing can be hindered if the permeability of a lava dome is reduced, promoting pore pressure augmentation and explosive beh...

Michael J. Heap, Valentin R. Troll, Alexandra R. L. Kushnir… in Nature Communications (2019)

Article

Interaction between high-temperature magmatic fluids and limestone explains ‘Bastnäs-type’ REE deposits in central Sweden

The presently increasing demand for rare earth elements (REE), particularly in high-tech and “green energy” applications, has led to global interest in the distribution, origins and formation conditions of REE...

Fredrik Sahlström, Erik Jonsson, Karin Högdahl, Valentin R. Troll… in Scientific Reports (2019)

Article

Complex hazard cascade culminating in the Anak Krakatau sector collapse

Flank instability and sector collapses, which pose major threats, are common on volcanic islands. On 22 Dec 2018, a sector collapse event occurred at Anak Krakatau volcano in the Sunda Strait, triggering a dea...

Thomas R. Walter, Mahmud Haghshenas Haghighi, Felix M. Schneider… in Nature Communications (2019)

Article

Crustal CO₂ contribution to subduction zone degassing recorded through calc-silicate xenoliths in arc lavas

Interaction between magma and crustal carbonate at active arc volcanoes has recently been proposed as a source of atmospheric CO₂, in addition to CO₂ released from the mantle and subducted oceanic crust. However,...

Sean Whitley, Ralf Gertisser, Ralf Halama, Katie Preece… in Scientific Reports (2019)

Article

Global Fe–O isotope correlation reveals magmatic origin of Kiruna-type apatite-iron-oxide ores

Kiruna-type apatite-iron-oxide ores are key iron sources for modern industry, yet their origin remains controversial. Diverse ore-forming processes have been discussed, comprising low-temperature hydrothermal ...

Valentin R. Troll, Franz A. Weis, Erik Jonsson, Ulf B. Andersson… in Nature Communications (2019)

Article

A large explosive silicic eruption in the British Palaeogene Igneous Province

Large-volume pyroclastic eruptions are not known from the basalt-dominated British Palaeogene Igneous Province (BPIP), although silicic magmatism is documented from intra-caldera successions in central volcano...

Valentin R. Troll, C. Henry Emeleus, Graeme R. Nicoll… in Scientific Reports (2019)

Article

Multi-level magma plumbing at Agung and Batur volcanoes increases risk of hazardous eruptions

The island of Bali in Indonesia is home to two active stratovolcanoes, Agung and Batur, but relatively little is known of their underlying magma plumbing systems. Here we define magma storage depths and isotop...

Harri Geiger, Valentin R. Troll, Ester M. Jolis, Frances M. Deegan… in Scientific Reports (2018)

Article

Magma reservoir dynamics at Toba caldera, Indonesia, recorded by oxygen isotope zoning in quartz

Quartz is a common phase in high-silica igneous rocks and is resistant to post-eruptive alteration, thus offering a reliable record of magmatic processes in silicic magma systems. Here we employ the 75 ka Toba...

David A. Budd, Valentin R. Troll, Frances M. Deegan, Ester M. Jolis… in Scientific Reports (2017)

Article

Erupted frothy xenoliths may explain lack of country-rock fragments in plutons

Magmatic sto** is discussed to be a main mechanism of magma emplacement. As a consequence of sto**, abundant country-rock fragments should occur within and at the bottom of, magma reservoirs as “xenolith g...

Steffi Burchardt, Valentin R. Troll, Harro Schmeling, Hemin Koyi… in Scientific Reports (2016)

Article

Locating the depth of magma supply for volcanic eruptions, insights from Mt. Cameroon

Mt. Cameroon is one of the most active volcanoes in Africa and poses a possible threat to about half a million people in the area, yet knowledge of the volcano’s underlying magma supply system is sparse. To ch...

Harri Geiger, Abigail K. Barker, Valentin R. Troll in Scientific Reports (2016)

Article

Boron isotope fractionation in magma via crustal carbonate dissolution

Carbon dioxide released by arc volcanoes is widely considered to originate from the mantle and from subducted sediments. Fluids released from upper arc carbonates, however, have recently been proposed to help ...

Frances M. Deegan, Valentin R. Troll, Martin J. Whitehouse… in Scientific Reports (2016)

Article

Magma transport in sheet intrusions of the Alnö carbonatite complex, central Sweden

Magma transport through the Earth’s crust occurs dominantly via sheet intrusions, such as dykes and cone-sheets and is fundamental to crustal evolution, volcanic eruptions and geochemical element cycling. Howe...

Magnus Andersson, Bjarne S. G. Almqvist, Steffi Burchardt… in Scientific Reports (2016)

Article

Nannofossils in 2011 El Hierro eruptive products reinstate plume model for Canary Islands

The origin and life cycle of ocean islands have been debated since the early days of Geology. In the case of the Canary archipelago, its proximity to the Atlas orogen led to initial fracture-controlled models ...

Kirsten Zaczek, Valentin R. Troll, Mario Cachao, Jorge Ferreira… in Scientific Reports (2015)

Article

Weibull-distributed dyke thickness reflects probabilistic character of host-rock strength

Magmatic sheet intrusions (dykes) constitute the main form of magma transport in the Earth’s crust. The size distribution of dykes is a crucial parameter that controls volcanic surface deformation and eruption...

Michael Krumbholz, Christoph F. Hieronymus, Steffi Burchardt… in Nature Communications (2014)

Article

Ardnamurchan 3D cone-sheet architecture explained by a single elongate magma chamber

The Palaeogene Ardnamurchan central igneous complex, NW Scotland, was a defining place for the development of the classic concepts of cone-sheet and ring-dyke emplacement and has thus fundamentally influenced ...

Steffi Burchardt, Valentin R. Troll, Lucie Mathieu, Henry C. Emeleus… in Scientific Reports (2013)

Article

Carbonatite ring-complexes explained by caldera-style volcanism

Carbonatites are rare, carbonate-rich magmatic rocks that make up a minute portion of the crust only, yet they are of great relevance for our understanding of crustal and mantle processes. Although they occur ...

Magnus Andersson, Alireza Malehmir, Valentin R. Troll… in Scientific Reports (2013)