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  • 1.
    Berg, S.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Troll, V.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Freda, C.
    Mancini, L.
    Masotta, M.
    Brun, F.
    Blythe, L.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Jolis, E. M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Annersten, H.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Barker, A.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Experimental simulation of crustal volatile release in magmatic conduits2012Konferensbidrag (Övrigt vetenskapligt)
  • 2.
    Blythe, L. S.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Misiti, V.
    Masotta, M
    Taddeucci, J.
    Freda, C.
    Troll, V. R.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Deegan, F. M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Jolis, E. M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Viscosity controlled magma-carbonate interaction: a comparison of Mt. Vesuvius (Italy) and Mt. Merapi (Indonesia)2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    Magma-carbonate interaction is increasingly seen as a viable and extremely important cause of magma contamination, and the generation of a crustally sourced CO2 phase (Goff et al., 2001; Freda et al., 2010). Even though the process is well recognized at certain volcanoes e.g. Popocatépetl, (Mexico); Merapi, (Indonesia); and Colli Albani, (Italy) (Goff et al., 2001; Deegan et al., 2010; Freda et al., 2010), neither the kinetics of carbonate assimilation nor its consequences for controlling the explosivity of eruptions have been constrained. Here we show the results of magma-carbonate interaction experiments conducted at 1200 °C and 0.5 GPa for varying durations (0 s, 60 s, 90 s and 300 s) for the Mt. Merapi (Indonesia) and Mt. Vesuvius (Italy) volcanic systems. We performed experiments using glassy starting materials specific to each volcano (shoshonite for Mt. Vesuvius, basaltic-andesite for Mt. Merapi) with different degrees of hydration (anhydrous vs hydration with ~ 2 wt % water) and using carbonate fragments of local origin; see Deegan et al., (2010) and Jolis et al., (2011). Experimental products include a gas phase (CO2-rich) and two melt phases, one pristine (Ca-normal) and one contaminated (Ca-rich) separated by a 'contamination front' which propagates outwards from the carbonate clast. Vesicles appear to nucleate in the contaminated glass and then migrate into the pristine one. Both contamination front propagation and bubble migration away from the carbonate are slower in anhydrous basaltic-andesite (Merapi anhydrous series) than in hydrated basaltic-andesite and shoshonite (Merapi and Vesuvius hydrated series), suggesting that assimilation speed is strongly controlled by the degree of hydration and the SiO2 content, both of which influence melt viscosity and hence diffusivity. As the carbonate dissolution proceeds in our experiments, initially dissolved and eventually exsolved CO2 builds up in the contaminated Ca-rich melt phase. Once melt volatile oversaturation is achieved, the reaction can only progress further if vesicles are efficiently removed from the contaminated melt phase. Viscosity, which controls the vesicle migration efficiency, thus ultimately determines the progression and rate of the contamination reaction. Our results show that characteristics of magma-carbonate interaction at different volcanic systems are likely to differ as a result of a volcanos' individual magma properties, especially viscosity, which determines the speed at which gaseous reaction products (i.e. CO2) can be removed from the reaction site.

  • 3.
    Blythe, L. S.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Troll, V. R.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Hilton, D.R.
    Deegan, F. M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Jolis, E. M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Stimac, J
    Chadwick, J. P.
    Chew, D.
    Magmatic vs crustal volatiles: a reconnaissance tool for geothermal energy2012Konferensbidrag (Refereegranskat)
  • 4.
    Blythe, Lara
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi. School of Physical and Geographical Science, Keele University, Keele, UK.
    Deegan, Frances
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Mineralogi, petrologi och tektonik. Department of Geological Sciences, Stockholm University, Stockholm, Sweden.
    Freda, C
    Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, Italy.
    Jolis, Ester Muños
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Mineralogi, petrologi och tektonik.
    Masotta, M
    Bayerisches Geoinstitut, Universität Bayreuth, Bayreuth, Germany.
    Misiti, V.
    Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, Italy.
    Taddeucci, J.
    Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, Italy.
    Troll, Valentin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Mineralogi, petrologi och tektonik. Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, Italy.
    CO2 bubble generation and migration during magma–carbonate interaction2015Ingår i: Contributions to Mineralogy and Petrology, ISSN 0010-7999, E-ISSN 1432-0967, Vol. 169, nr 4, artikel-id 42Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We conducted quantitative textural analysis of vesicles in high temperature and pressure carbonate assimilation experiments (1200 °C, 0.5 GPa) to investigate CO2 generation and subsequent bubble migration from carbonate into magma. We employed Mt. Merapi (Indonesia) and Mt. Vesuvius (Italy) compositions as magmatic starting materials and present three experimental series using (1) a dry basaltic-andesite, (2) a hydrous basaltic-andesite (2 wt% H2O), and (3) a hydrous shoshonite (2 wt% H2O). The duration of the experiments was varied from 0 to 300 s, and carbonate assimilation produced a CO2-rich fluid and CaO-enriched melts in all cases. The rate of carbonate assimilation, however, changed as a function of melt viscosity, which affected the 2D vesicle number, vesicle volume, and vesicle size distribution within each experiment. Relatively low-viscosity melts (i.e. Vesuvius experiments) facilitated efficient removal of bubbles from the reaction site. This allowed carbonate assimilation to continue unhindered and large volumes of CO2 to be liberated, a scenario thought to fuel sustained CO2-driven eruptions at the surface. Conversely, at higher viscosity (i.e. Merapi experiments), bubble migration became progressively inhibited and bubble concentration at the reaction site caused localised volatile over-pressure that can eventually trigger short-lived explosive outbursts. Melt viscosity therefore exerts a fundamental control on carbonate assimilation rates and, by consequence, the style of CO2-fuelled eruptions.

  • 5.
    Blythe, Lara
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Deegan, Frances
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Freda, C.
    Jolis, Ester Muños
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Masotta, M.
    Misiti, V.
    Taddeucci, J.
    Troll, V.R.
    Time-monitored vesiculation processes in magma-carbonate interaction experiments2014Ingår i: Contributions to Mineralogy and Petrology, ISSN 0010-7999, E-ISSN 1432-0967Artikel i tidskrift (Övrigt vetenskapligt)
  • 6.
    Blythe, Lara S.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Understanding Crustal Volatiles: Provenance,  Processes and Implications2012Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Knowledge of the provenance of crustal volatiles and the processes by which they are released is extremely important for the dynamics of magmatic systems. Presented here are the results of multiple investigations, which aim to understand magmatic volatile contamination from contrasting but complementary perspectives. The main methodologies used include He and C isotope values and CO2/3He ratios of volcanic gases and fluids; simulation of magma-carbonate interaction using high-pressure high-temperature experimental petrology; X-ray microtomography of vesiculated xenoliths and computer modeling.

    Findings show that the contribution from upper crustal volatiles can be substantial, and is dependant on the upper crustal lithology on which a volcano lies, as well as the composition of the magma supplied. Carbonate dissolution in particular is strongly controlled by the viscosity of the host magma. The details of the breakdown of vesiculated xenoliths is complex but has wide reaching implications, ranging from the dissemination of crustally derived materials through a magma body to highlighting that crustal volatiles are largely unaccounted for in both individual volcano and global volatile budgets. In synthesizing the conclusions from each of the individual perspectives presented, I propose the contribution of volatiles from crustal sources to play a significant role in many geological systems. This volatile component should be taken into consideration in future research efforts.

    Delarbeten
    1. Mantle versus crustal volatile sources along the Java – Bali segment of the Sunda arc, Indonesia.
    Öppna denna publikation i ny flik eller fönster >>Mantle versus crustal volatile sources along the Java – Bali segment of the Sunda arc, Indonesia.
    (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Nyckelord
    Helium isotopes, carbon isotopes, Indonesia, volcanic gases and fluids, upper crustal volatile contamination, GAC, JAC
    Nationell ämneskategori
    Geokemi Geologi
    Forskningsämne
    Geovetenskap med inriktning mot mineralogi, petrologi och tektonik
    Identifikatorer
    urn:nbn:se:uu:diva-171478 (URN)
    Tillgänglig från: 2012-03-19 Skapad: 2012-03-19 Senast uppdaterad: 2012-04-13
    2. Concentration of commercially-viable geothermal resources in W-Java controlled by crustal thickness and composition
    Öppna denna publikation i ny flik eller fönster >>Concentration of commercially-viable geothermal resources in W-Java controlled by crustal thickness and composition
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    (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Nationell ämneskategori
    Geokemi Geologi
    Forskningsämne
    Geovetenskap med inriktning mot mineralogi, petrologi och tektonik
    Identifikatorer
    urn:nbn:se:uu:diva-171480 (URN)
    Tillgänglig från: 2012-03-19 Skapad: 2012-03-19 Senast uppdaterad: 2012-04-13
    3. Time-monitored vesiculation and dissolution during magma-carbonate interaction experiments: Merapi (Indonesia) and Vesuvius (Italy).
    Öppna denna publikation i ny flik eller fönster >>Time-monitored vesiculation and dissolution during magma-carbonate interaction experiments: Merapi (Indonesia) and Vesuvius (Italy).
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    (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Nyckelord
    Merapi, Vesuvius, carbonate assimilation, volatile exsolution, carbon dioxide, viscosity, bubbles, vesicles
    Nationell ämneskategori
    Multidisciplinär geovetenskap Geologi
    Identifikatorer
    urn:nbn:se:uu:diva-171481 (URN)
    Tillgänglig från: 2012-03-19 Skapad: 2012-03-19 Senast uppdaterad: 2012-04-13
    4. Floating stones off El Hierro, Canary Islands: xenoliths of pre-island sedimentary origin in the early products of the October 2011 eruption
    Öppna denna publikation i ny flik eller fönster >>Floating stones off El Hierro, Canary Islands: xenoliths of pre-island sedimentary origin in the early products of the October 2011 eruption
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    2012 (Engelska)Ingår i: Solid Earth, ISSN 1869-9510, E-ISSN 1869-9529, Vol. 3, nr 1, s. 97-110Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    A submarine eruption started off the south coast of El Hierro, Canary Islands, on 10 October 2011 and continues at the time of this writing (February 2012). In the first days of the event, peculiar eruption products were found floating on the sea surface, drifting for long distances from the eruption site. These specimens, which have in the meantime been termed "restingolites" (after the close-by village of La Restinga), appeared as black volcanic "bombs" that exhibit cores of white and porous pumice-like material. Since their brief appearance, the nature and origin of these "floating stones" has been vigorously debated among researchers, with important implications for the interpretation of the hazard potential of the ongoing eruption. The "restingolites" have been proposed to be either (i) juvenile high-silica magma (e. g. rhyolite), (ii) remelted magmatic material (trachyte), (iii) altered volcanic rock, or (iv) reheated hyaloclastites or zeolite from the submarine slopes of El Hierro. Here, we provide evidence that supports yet a different conclusion. We have analysed the textures and compositions of representative "restingolites" and compared the results to previous work on similar rocks found in the Canary Islands. Based on their high-silica content, the lack of igneous trace element signatures, the presence of remnant quartz crystals, jasper fragments and carbonate as well as wollastonite (derived from thermal overprint of carbonate) and their relatively high oxygen isotope values, we conclude that "restingolites" are in fact xenoliths from pre-island sedimentary layers that were picked up and heated by the ascending magma, causing them to partially melt and vesiculate. As they are closely resembling pumice in appearance, but are xenolithic in origin, we refer to these rocks as "xeno-pumice". The El Hierro xeno-pumices hence represent messengers from depth that help us to understand the interaction between ascending magma and crustal lithologies beneath the Canary Islands as well as in similar Atlantic islands that rest on sediment-covered ocean crust (e. g. Cape Verdes, Azores). The occurrence of "restingolites" indicates that crustal recycling is a relevant process in ocean islands, too, but does not herald the arrival of potentially explosive high-silica magma in the active plumbing system beneath El Hierro.

    Ort, förlag, år, upplaga, sidor
    Copernicus Publications, 2012
    Nationell ämneskategori
    Geologi Geokemi
    Identifikatorer
    urn:nbn:se:uu:diva-171483 (URN)10.5194/se-3-97-2012 (DOI)000309884400008 ()
    Forskningsfinansiär
    Vetenskapsrådet
    Anmärkning

    Correction in Solid Earth. Vol. 3(2) p. 189. DOI: 10.5194/se-3-189-2012

    Tillgänglig från: 2012-03-19 Skapad: 2012-03-19 Senast uppdaterad: 2019-10-03Bibliografiskt granskad
    5. A global record of xeno-pumice: evidence for magma-crust interaction and crustal volatile remobilisation.
    Öppna denna publikation i ny flik eller fönster >>A global record of xeno-pumice: evidence for magma-crust interaction and crustal volatile remobilisation.
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    (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Nyckelord
    crustal volatiles, xenoliths, xeno-pumice, assimilation, contamination, explosive eruptive activity, X-ray microtomography, volcanic volatile budgets
    Nationell ämneskategori
    Geologi
    Forskningsämne
    Geovetenskap med inriktning mot mineralogi, petrologi och tektonik
    Identifikatorer
    urn:nbn:se:uu:diva-171484 (URN)
    Tillgänglig från: 2012-03-19 Skapad: 2012-03-19 Senast uppdaterad: 2012-04-13
    6. Sink or swim: The fate of crustal xenoliths in shallow magma chambers
    Öppna denna publikation i ny flik eller fönster >>Sink or swim: The fate of crustal xenoliths in shallow magma chambers
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    (Engelska)Ingår i: Artikel i tidskrift (Övrigt vetenskapligt) Submitted
    Nyckelord
    xenolith, magmatic stoping, assimmilation, magma contamination, pluton emplacement, magma chamber dynamics
    Nationell ämneskategori
    Geologi
    Identifikatorer
    urn:nbn:se:uu:diva-171485 (URN)
    Tillgänglig från: 2012-03-19 Skapad: 2012-03-19 Senast uppdaterad: 2017-01-25
  • 7.
    Burchardt, Steffi
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Mineralogi, petrologi och tektonik.
    Troll, Valentin R.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Mineralogi, petrologi och tektonik.
    Schmeling, Harro
    Goethe Univ Frankfurt, Fac Earth Sci, Altenhoferallee 1, D-60438 Frankfurt, Germany..
    Koyi, Hemin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Mineralogi, petrologi och tektonik.
    Blythe, Lara
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Erupted frothy xenoliths may explain lack of country-rock fragments in plutons2016Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, artikel-id 34566Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Magmatic stoping is discussed to be a main mechanism of magma emplacement. As a consequence of stoping, abundant country-rock fragments should occur within, and at the bottom of, magma reservoirs as "xenolith graveyards", or become assimilated. However, the common absence of sufficient amounts of both xenoliths and crustal contamination have led to intense controversy about the efficiency of stoping. Here, we present new evidence that may explain the absence of abundant country-rock fragments in plutons. We report on vesiculated crustal xenoliths in volcanic rocks that experienced devolatilisation during heating and partial melting when entrained in magma. We hypothesise that the consequential inflation and density decrease of the xenoliths allowed them to rise and become erupted instead of being preserved in the plutonic record. Our thermomechanical simulations of this process demonstrate that early-stage xenolith sinking can be followed by the rise of a heated, partially-molten xenolith towards the top of the reservoir. There, remnants may disintegrate and mix with resident magma or erupt. Shallow-crustal plutons emplaced into hydrous country rocks may therefore not necessarily contain evidence of the true amount of magmatic stoping during their emplacement. Further studies are needed to quantify the importance of frothy xenolith in removing stoped material.

  • 8.
    Burchardt, Steffi
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Troll, Valentin R
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Schmeling, Harro
    Faculty of Earth Sciences, J. W. Goethe Universität, Altenhöferallee 1, 60438 Frankfurt am Main, Germany.
    Koyi, Hemin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Blythe, Lara
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Sink or swim: The fate of crustal xenoliths in shallow magma chambersIngår i: Artikel i tidskrift (Övrigt vetenskapligt)
  • 9.
    Deegan, Frances
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Troll, Valentin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Jolis, Ester Muños
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Freda, C.
    Hilton, D.R.
    Budd, David
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Gertisser, R.
    Blythe, Lara
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Chadwick, J.P.
    Schwarzkopf, L.M.
    Zimmer, M
    The role of CO2-rich basement at Merapi; perspectives from petrology, geochemistry, and experiments2014Konferensbidrag (Refereegranskat)
  • 10.
    Jolis, E. M.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Troll, V. R.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Deegan, F. M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Blythe, L. S.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Harris, C.
    Freda, C.
    Hilton, D.
    Chadwick, J.
    van Helden, M.
    Tracing crustal contamination along the Java segment of the Sunda Arc, Indonesia2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    Arc magmas typically display chemical and petrographic characteristics indicative of crustal input. Crustal contamination can take place either in the mantle source region or as magma traverses the upper crust (e.g. [1]). While source contamination is generally considered the dominant process (e.g. [2]), late-stage crustal contamination has been recognised at volcanic arcs too (e.g. [3]). In light of this, we aim to test the extent of upper crustal versus source contamination along the Java segment of the Sunda arc, which, due its variable upper crustal structure, is an exemplary natural laboratory. We present a detailed geochemical study of 7 volcanoes along a traverse from Anak-Krakatau in the Sunda strait through Java and Bali, to characterise the impact of the overlying crust on arc magma composition. Using rock and mineral elemental geochemistry, radiogenic (Sr, Nd and Pb) and, stable (O) isotopes, we show a correlation between upper crustal composition and the degree of upper crustal contamination. We find an increase in 87Sr/86Sr and δ18O values, and a decrease in 143Nd/144Nd values from Krakatau towards Merapi, indicating substantial crustal input from the thick continental basement present. Volcanoes to the east of Merapi and the Progo-Muria fault transition zone, where the upper crust is thinner, in turn, show considerably less crustal input in their isotopic signatures, indicating a stronger influence of the mantle source. Our new data represent a systematic and high-resolution arc-wide sampling effort that allows us to distinguish the effects of the upper crust on the compositional spectrum of individual volcanic systems along the Sunda arc. [1] Davidson, J.P, Hora, J.M, Garrison, J.M & Dungan, M.A 2005. Crustal Forensics in Arc Magmas. J. Geotherm. Res. 140, 157-170; [2] Debaille, V., Doucelance, R., Weis, D., & Schiano, P. 2005. Geochim. Cosmochim. Acta, 70,723-741; [3] Gasparon, M., Hilton, D.R., & Varne, R. 1994. Earth Planet. Sci. Lett., 126, 15-22.

  • 11.
    Jolis, E. M.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Troll, V. R.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Deegan, F. M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Blythe, L. S.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Harris, C
    Freda, C
    Hilton, D.
    Chadwick, J.
    van Helden, M.
    Tracing crustal contamination along the Java segment of the Sunda Arc, Indonesia2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    Arc magmas typically display chemical and petrographic characteristics indicative of crustal input. Crustal contamination can take place either in the mantle source region or as magma traverses the crust (e.g. [1]). While source contamination is generally considered the dominant process (e.g. [2, 3, 4]), crustal contamination in high level magma chambers has also been recognised at volcanic arcs (e.g. [5, 6]). In light of this, we aim to test the extent of upper crustal versus source contamination along the Java segment of the Sunda arc, which, because of its variable upper crustal structure, is ideal for the task.

    We present a detailed geochemical study of 7 volcanoes along a traverse from Anak-Krakatau in the Sunda strait through Java (Gede, Slamet, Merapi, Kelut, Kawah-Ijen) and Bali (Batur). Using rock and mineral elemental geochemistry and radiogenic (Sr, Nd and Pb) and, stable (O) isotopes, we show a correspondence between changes in composition of the upper crust and the apparent degree of upper crustal contamination. There is an increase in 87Sr/86Sr and δ18O, and a decrease in 143Nd/144Nd from Krakatau towards Merapi, indicating substantial input from the thick quasi-continental basement beneath East and Central Java. Volcanoes to the east of Merapi, and the Progo-Muria fault zone, where the upper crust is thinner and increasingly oceanic in nature have lower 87Sr/86Sr and δ18O, and higher 143Nd/144Nd indicating a stronger influence of the mantle source [7]. Our new data represent a systematic and high-resolution arc-wide sampling effort that allows us to distinguish the effects of the upper crust on the compositional spectrum of individual volcanic systems along the Sunda arc.

     

     

    [1] Davidson, J.P, Hora, J.M, Garrison, J.M & Dungan, M.A (2005), J. Geotherm. Res., 140, 157-170.

    [2] Hilton, D.R., Fischer, T.P. & Marty, B. (2002), Rev. Mineral. Geochem., 47, 319-370.

    [3] Gertisser, R. & Keller, J. (2003). J. Petrol., 44, 457-489

    [4] Debaille, V., Doucelance, R., Weis, D., & Schiano, P. (2005), Geochim. Cosmochim. Acta, 70,723-741.

    [5] Gasparon, M., Hilton, D.R., & Varne, R. (1994), Earth Planet. Sci. Lett., 126, 15-22.

    [6] Chadwick, J.P., Troll, V.R., Ginibre, C., Morgan, D., Gertisser, R., Waight, T.E. & Davidson, J.P. (2007), J. Petrol., 48, 1793-1812.

    [7] Whitford, D.J. (1975), Geochim. Cosmochim. Acta, 39, 1287-1302.

  • 12.
    Jolis, Ester M.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Freda, Carmela
    Istituto Nazionale di Geofisica e Vulcanologia, INGV, Rome.
    Troll, Valentin R
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Deegan, Frances M.
    Dept. of Geoscience, Swedish Museum of Natural History, Stockholm.
    Blythe, Lara
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    McLeod, Claire L.
    University of Houston.
    Davidson, Jon P.
    Durham University.
    Experimental simulation of magma-carbonate interaction beneath Mt. Vesuvius, Italy2012Ingår i: Annual Report 2012, HP-HT Laboratory of experimental Volcanology and Geophysics, s. 163-166Artikel i tidskrift (Refereegranskat)
  • 13.
    Jolis, Ester Muñoz
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Freda, C.
    Troll, Valentin R.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Deegan, Frances M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Blythe, Lara S.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    McLeod, C. L.
    Davidson, J. P.
    Experimental simulation of magma-carbonate interaction beneath Mt. Vesuvius, Italy2013Ingår i: Contributions to Mineralogy and Petrology, ISSN 0010-7999, E-ISSN 1432-0967, Vol. 166, nr 5, s. 1335-1353Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We simulated the process of magma-carbonate interaction beneath Mt. Vesuvius in short duration piston-cylinder experiments under controlled magmatic conditions (from 0 to 300 s at 0.5 GPa and 1,200 A degrees C), using a Vesuvius shoshonite composition and upper crustal limestone and dolostone as starting materials. Backscattered electron images and chemical analysis (major and trace elements and Sr isotopes) of sequential experimental products allow us to identify the textural and chemical evolution of carbonated products during the assimilation process. We demonstrate that melt-carbonate interaction can be extremely fast (minutes), and results in dynamic contamination of the host melt with respect to Ca, Mg and Sr-87/Sr-86, coupled with intense CO2 vesiculation at the melt-carbonate interface. Binary mixing between carbonate and uncontaminated melt cannot explain the geochemical variations of the experimental charges in full and convection and diffusion likely also operated in the charges. Physical mixing and mingling driven by exsolving volatiles seems to be a key process to promote melt homogenisation. Our results reinforce hypotheses that magma-carbonate interaction is a relevant and ongoing process at Mt. Vesuvius and one that may operate not only on a geological, but on a human timescale.

  • 14.
    Troll, Valentin
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Dahrén, Börje
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Deegan, Frances
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Jolis, Ester Muños
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Blythe, Lara
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Harris, C.
    Berg, Sylvia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Hilton, D.R.
    Freda, C.
    Reconstructing the plumbing system of Krakatau volcano2014Konferensbidrag (Refereegranskat)
  • 15.
    Troll, Valentin
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Deegan, Frances
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Jolis, Ester Muños
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Dahrén, Börje
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Blythe, Lara
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Harris, C.
    Berg, Sylvia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Hilton, D.R.
    Freda, C.
    Magma storage at Krakatau volcanic complex2014Konferensbidrag (Refereegranskat)
  • 16.
    Troll, Valentin
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Klügel, A
    3Institute of Geosciences, University of Bremen, Germany.
    Longpré, M.-A
    Dept. of Earth and Planetary Sciences, McGill University, Canada.
    Burchardt, Steffi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Deegan, Frances
    Laboratory for Isotope Geology, Swedish Museum of Natural History, Stockhom, Sweden..
    Carracedo, J.C
    Dept. of Physics (Geology), GEOVOL, University of Las Palmas, Gran Canaria, Spain.
    Wiesmaier, S
    Dept. of Earth and Environmental Sciences, Ludwig-Maximilians Universität (LMU), Munich, Germany.
    Kueppers, U
    Dept. of Earth and Environmental Sciences, Ludwig-Maximilians Universität (LMU), Munich, Germany.
    Dahrén, Börje
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Blythe, Lara
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Hansteen, T. H
    Leibniz-Institute for Oceanography, IFM-GEOMAR, Kiel, Germany.
    Freda, Carmela
    Istituto Nazionale di Geofisica e Vulcanologia, Rome, Italy.
    Budd, David
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Jolis, Ester
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Jonsson, E
    Geological Survey of Sweden, Uppsala, Sweden.
    Meade, Fiona
    School of Geographical and Earth Sciences, University of Glasgow, UK.
    Harris, Chris
    Department of Geological Sciences, University of Cape Town, South Africa.
    Berg, Sylvia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Mancini, Lucia
    SYRMEP Group, Sincrotrone Trieste S.C.p.A, Basovizza, Trieste, Italy.
    Polacci, M
    Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Pisa, 56124 Pisa, Italy.
    Pedroza, Kirsten
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Floating stones off El Hierro, Canary Islands: xenoliths of pre-island sedimentary origin in the early products of the October 2011 eruption2012Ingår i: Solid Earth, ISSN 1869-9510, E-ISSN 1869-9529, Vol. 3, nr 1, s. 97-110Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A submarine eruption started off the south coast of El Hierro, Canary Islands, on 10 October 2011 and continues at the time of this writing (February 2012). In the first days of the event, peculiar eruption products were found floating on the sea surface, drifting for long distances from the eruption site. These specimens, which have in the meantime been termed "restingolites" (after the close-by village of La Restinga), appeared as black volcanic "bombs" that exhibit cores of white and porous pumice-like material. Since their brief appearance, the nature and origin of these "floating stones" has been vigorously debated among researchers, with important implications for the interpretation of the hazard potential of the ongoing eruption. The "restingolites" have been proposed to be either (i) juvenile high-silica magma (e. g. rhyolite), (ii) remelted magmatic material (trachyte), (iii) altered volcanic rock, or (iv) reheated hyaloclastites or zeolite from the submarine slopes of El Hierro. Here, we provide evidence that supports yet a different conclusion. We have analysed the textures and compositions of representative "restingolites" and compared the results to previous work on similar rocks found in the Canary Islands. Based on their high-silica content, the lack of igneous trace element signatures, the presence of remnant quartz crystals, jasper fragments and carbonate as well as wollastonite (derived from thermal overprint of carbonate) and their relatively high oxygen isotope values, we conclude that "restingolites" are in fact xenoliths from pre-island sedimentary layers that were picked up and heated by the ascending magma, causing them to partially melt and vesiculate. As they are closely resembling pumice in appearance, but are xenolithic in origin, we refer to these rocks as "xeno-pumice". The El Hierro xeno-pumices hence represent messengers from depth that help us to understand the interaction between ascending magma and crustal lithologies beneath the Canary Islands as well as in similar Atlantic islands that rest on sediment-covered ocean crust (e. g. Cape Verdes, Azores). The occurrence of "restingolites" indicates that crustal recycling is a relevant process in ocean islands, too, but does not herald the arrival of potentially explosive high-silica magma in the active plumbing system beneath El Hierro.

  • 17.
    Troll, Valentin R
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Chadwick, Jane P.
    Science Gallery, Trinity College Dublin, Dublin.
    Jolis, Ester M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Deegan, Frances M.
    Dept. of Geoscience, Swedish Museum of Natural History, Stockholm.
    Hilton, David
    Geosciences Research Division, Scripps Institution of Oceanography, La Jolla, USA .
    Schwarzkopf, Lothar M.
    GeoDocCon, Konradsreuth, Germany.
    Blythe, Lara
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Zimmer, Martin
    Helmholtz – Centre Potsdam, GFZ, Potsdam, Germany.
    Crustal volatile release at Merapi volcano; the 2006 earthquake and eruption events2013Ingår i: Geology Today, ISSN 0266-6979, E-ISSN 1365-2451, Vol. 29, nr 3, s. 96-101Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 18.
    Troll, Valentin R.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Hilton, David R.
    Jolis, Ester M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Chadwick, Jane P.
    Blythe, Lara S.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Deegan, Frances M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Berggrundsgeologi.
    Schwarzkopf, Lothar M.
    Zimmer, Martin
    Crustal CO2 liberation during the 2006 eruption and earthquake events at Merapi volcano, Indonesia2012Ingår i: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 39, s. L11302-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    High-temperature volcanic gas is widely considered to originate from ascending, mantle-derived magma. In volcanic arc systems, crustal inputs to magmatic gases mainly occur via subducted sediments in the mantle source region. Our data from Merapi volcano, Indonesia imply, however, that during the April-October 2006 eruption significant quantities of CO2 were added from shallow crustal sources. We show that prior to the 2006 events, summit fumarole gas delta C-13((CO2)) is virtually constant (delta C-13(1994-2005) = -4.1 +/- 0.3 parts per thousand), but during the 2006 eruption and after the shallow Yogyakarta earthquake of late May, 2006 (M6.4; hypocentres at 10-15 km depth), carbon isotope ratios increased to -2.4 +/- 0.2 parts per thousand. This rise in delta C-13 is consistent with considerable addition of crustal CO2 and coincided with an increase in eruptive intensity by a factor of similar to 3 to 5. We postulate that this shallow crustal volatile input supplemented the mantle-derived volatile flux at Merapi, intensifying and sustaining the 2006 eruption. Late-stage volatile additions from crustal contamination may thus provide a trigger for explosive eruptions independently of conventional magmatic processes.

1 - 18 av 18
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