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Article
Open AccessCrustal 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,...
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Article
Open AccessGlobal 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 ...
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Article
Open AccessA 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...
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Article
Open AccessMulti-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...
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Chapter
Alnö Minerals
Alnö is famed for its unusual richness in rare minerals that often occur in collector quality within and around the Alnö igneous complex. This chapter provides a list of all major mineral phases found in N-Aln...
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Chapter
Excursion Guide
This chapter offers a series of organised excursions on the island of Alnö and to several locations north of Alnö, including the Sälkär skerries and the Söråker intrusion. The excursions will bring the visitor...
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Chapter
An Introduction to Carbonatites and Carbonatite Complexes
The Alnö igneous complex intruded local migmatites and granite country-rocks of Svecofennian age at ~580 Ma and produced a suite of early alkaline silicate intrusives (e.g., ijolites, nepheline syenites) and d...
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Chapter
Geochemistry and Alnö as an Economic Reserve
The compositional spectrum of Alnö rocks is discussed in respect to major, and trace elements as well as for stable and radiogenic isotopes (O, Sr, Nd). The evidence points to a deep mantle, possibly OIB, orig...
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Article
Amphibole megacrysts as a probe into the deep plumbing system of Merapi volcano, Central Java, Indonesia
Amphibole has been discussed to potentially represent an important phase during early chemical evolution of arc magmas, but is not commonly observed in eruptive arc rocks. Here, we present an in-depth study of...
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Article
Open AccessMagma 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...
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Article
Open AccessErupted 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...
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Article
Open AccessLocating 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...
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Article
Open AccessBoron 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 ...
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Article
Open AccessMagma 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...
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Article
The magma plumbing system for the 1971 Teneguía eruption on La Palma, Canary Islands
The 1971 Teneguía eruption is the most recent volcanic event of the Cumbre Vieja rift zone on La Palma. The eruption produced basanite lavas that host xenoliths, which we investigate to provide insight into th...
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Article
Open AccessNannofossils 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 ...
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Article
Open AccessWeibull-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...
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Article
Open AccessArdnamurchan 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 ...
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Article
Textural history of recent basaltic-andesites and plutonic inclusions from Merapi volcano
Mt. Merapi in Central Java is one of the most active stratovolcanoes on Earth and is underlain by a multistage plumbing system. Crystal size distribution analyses (CSD) were carried out on recent Merapi basalt...
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Article
Open AccessCarbonatite 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 ...
