Articles | Volume 35, issue 6
https://doi.org/10.5194/ejm-35-1125-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/ejm-35-1125-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Retrogression of ultrahigh-pressure eclogite, Western Gneiss Region, Norway
Dirk Spengler
CORRESPONDING AUTHOR
Faculty of Geology, Geophysics and Environmental Protection, AGH University of Krakow, 30-059 Kraków, Poland
Adam Włodek
Faculty of Geology, Geophysics and Environmental Protection, AGH University of Krakow, 30-059 Kraków, Poland
Xin Zhong
Institut für Geologische Wissenschaften, Freie Universität Berlin, 12449 Berlin, Germany
Anselm Loges
Institut für Geologische Wissenschaften, Freie Universität Berlin, 12449 Berlin, Germany
Simon J. Cuthbert
Faculty of Geology, Geophysics and Environmental Protection, AGH University of Krakow, 30-059 Kraków, Poland
Related authors
Dirk Spengler, Monika Koch-Müller, Adam Włodek, Simon J. Cuthbert, and Jarosław Majka
EGUsphere, https://doi.org/10.5194/egusphere-2024-2734, https://doi.org/10.5194/egusphere-2024-2734, 2024
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West Norwegian 'diamond facies' eclogite contains tiny mineral inclusions of quartz and amphibole lamellae that are not stable in the diamond field. Low trace amounts of water in the lamellae-bearing host minerals suggest that the inclusion microstructure was not formed by fluid infiltration but by dehydration during early exhumation of these rocks. Some samples with higher water content argue that a late fluid overprint was spatially restricted and obliterated evidence of extreme metamorphism.
Dirk Spengler, Monika Koch-Müller, Adam Włodek, Simon J. Cuthbert, and Jarosław Majka
EGUsphere, https://doi.org/10.5194/egusphere-2024-2734, https://doi.org/10.5194/egusphere-2024-2734, 2024
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West Norwegian 'diamond facies' eclogite contains tiny mineral inclusions of quartz and amphibole lamellae that are not stable in the diamond field. Low trace amounts of water in the lamellae-bearing host minerals suggest that the inclusion microstructure was not formed by fluid infiltration but by dehydration during early exhumation of these rocks. Some samples with higher water content argue that a late fluid overprint was spatially restricted and obliterated evidence of extreme metamorphism.
Anselm Loges, Gudrun Scholz, Nader de Sousa Amadeu, Jingjing Shao, Dina Schultze, Jeremy Fuller, Beate Paulus, Franziska Emmerling, Thomas Braun, and Timm John
Eur. J. Mineral., 34, 507–521, https://doi.org/10.5194/ejm-34-507-2022, https://doi.org/10.5194/ejm-34-507-2022, 2022
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We investigated the effect that fluoride and protons have on each other as structural neighbors in the mineral topaz. This was done using spectroscopic methods, which measure the interaction of electromagnetic radiation with matter. The forces between atoms distort the spectroscopic signals, and this distortion can thus be used to understand the corresponding forces and their effect on the physical properties of the mineral.
Gerhard Franz, Martin Kutzschbach, Eleanor J. Berryman, Anette Meixner, Anselm Loges, and Dina Schultze
Eur. J. Mineral., 33, 401–423, https://doi.org/10.5194/ejm-33-401-2021, https://doi.org/10.5194/ejm-33-401-2021, 2021
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Metamorphic rocks contain information about their original rocks and thus provide insight into the earlier stages of a region of interest. Here, we used the whole-rock chemical composition and stable boron isotopes of a suite of rocks from the Alps (Italy–Austria), which were deposited in a restricted intramontane basin before the Alpine orogeny. It is possible to reconstruct the depositional conditions for these sediments, which are now common metamorphic rocks such as schists and gneisses.
Related subject area
Metamorphic petrology
The composition of metapelitic biotite, white mica, and chlorite: a review with implications for solid-solution models
Comparison between 2D and 3D microstructures and implications for metamorphic constraints using a chloritoid–garnet-bearing mica schist
Sedimentary protolith and high-P metamorphism of oxidized manganiferous quartzite from the Lanterman Range, northern Victoria Land, Antarctica
Metamorphic evolution of sillimanite gneiss in the high-pressure terrane of the Western Gneiss Region (Norway)
Halogen-bearing metasomatizing melt preserved in high-pressure (HP) eclogites of Pfaffenberg, Bohemian Massif
Île Dumet (Armorican Massif, France) and its glaucophane eclogites: the little sister of Île de Groix
Electron backscatter diffraction analysis combined with NanoSIMS U–Pb isotope data reveal intra-grain plastic deformation in zircon and its effects on U–Pb age: examples from Himalayan eclogites, Pakistan
H2O and Cl in deep crustal melts: the message of melt inclusions in metamorphic rocks
Very-low-grade phyllosilicates in the Aravis massif (Haute-Savoie, France) and the di-trioctahedral substitution in chlorite
Partial melting of amphibole–clinozoisite eclogite at the pressure maximum (eclogite type locality, Eastern Alps, Austria)
Petrological study of an eclogite-facies metagranite from the Champtoceaux Complex (La Picherais, Armorican Massif, France)
Corundum-bearing and spinel-bearing symplectites in ultrahigh-pressure eclogites record high-temperature overprint and partial melting during slab exhumation
Some thoughts about eclogites and related rocks
Metamorphic P–T paths of Archean granulite facies metasedimentary lithologies from the eastern Beartooth Mountains of the northern Wyoming Province, Montana, USA: constraints from quartz-in-garnet (QuiG) Raman elastic barometry, geothermobarometry, and thermodynamic modeling
Detrital garnet petrology challenges Paleoproterozoic ultrahigh-pressure metamorphism in western Greenland
Equilibrium and kinetic approaches to understand the occurrence of the uncommon chloritoid + biotite assemblage
Geochemistry and paleogeographic implications of Permo-Triassic metasedimentary cover from the Tauern Window (Eastern Alps)
Reaction progress of clay minerals and carbonaceous matter in a contact metamorphic aureole (Torres del Paine intrusion, Chile)
Partial melting of zoisite eclogite from the Sanddal area, North-East Greenland Caledonides
Benoît Dubacq and Jacob B. Forshaw
Eur. J. Mineral., 36, 657–685, https://doi.org/10.5194/ejm-36-657-2024, https://doi.org/10.5194/ejm-36-657-2024, 2024
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This article reviews the crystal chemistry of chlorite, biotite, and white mica in metamorphosed sediments. These minerals have complex compositions because many atom exchanges may take place in their structure. Such exchanges include easily measured cations but also structurally bound H2O, notoriously hard to measure; iron oxidation; and vacancies. Consequently, formula units are often calculated from incomplete measurements and some exchanges may appear solely due to normalization issues.
Fabiola Caso, Alessandro Petroccia, Sara Nerone, Andrea Maffeis, Alberto Corno, and Michele Zucali
Eur. J. Mineral., 36, 381–395, https://doi.org/10.5194/ejm-36-381-2024, https://doi.org/10.5194/ejm-36-381-2024, 2024
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Despite the fact that rock textures depend on the 3D spatial distribution of minerals, our tectono-metamorphic reconstructions are mostly based on a 2D visualisation (i.e. thin sections). For 2D a thin section scan has been combined with chemical X-ray maps, whereas for 3D the X-ray computerised axial microtomography (μCT) has been applied. This study corroborates the reliability of the thin section approach, still emphasising that 3D visualisation can help understand rock textures.
Taehwan Kim, Yoonsup Kim, Simone Tumiati, Daeyeong Kim, Keewook Yi, and Mi Jung Lee
Eur. J. Mineral., 36, 323–343, https://doi.org/10.5194/ejm-36-323-2024, https://doi.org/10.5194/ejm-36-323-2024, 2024
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The manganese-rich siliceous metasediment in the Antarctic Ross orogen most likely originated from Mn-nodule-bearing chert deposited not earlier than ca. 546 Ma. Subduction-related metamorphism resulted in the production of highly oxidized assemblages involving Mn3+ and rare-earth-element-zoned epidote-group mineral and Mn2+-rich garnet. A reduced environment was responsible for the Mn olivine-bearing assemblages from silica-deficient composition.
Ane K. Engvik and Johannes Jakob
Eur. J. Mineral., 36, 345–360, https://doi.org/10.5194/ejm-36-345-2024, https://doi.org/10.5194/ejm-36-345-2024, 2024
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The paper documents sillimanite gneiss in the Western Gneiss Region (WGR) and its presence, composition, formation and metamorphic evolution. Peak metamorphism is modelled to T = 750 °C and P around 0.6 GPa. Subsequent retrogression consumes garnet and shows mineral replacement and melt crystallization involving sillimanite, white mica, K-feldspar and quartz. The petrological evolution is in accordance with the investigated eclogites and HP granulites in the northwestern part of WGR.
Alessia Borghini, Silvio Ferrero, Patrick J. O'Brien, Bernd Wunder, Peter Tollan, Jarosław Majka, Rico Fuchs, and Kerstin Gresky
Eur. J. Mineral., 36, 279–300, https://doi.org/10.5194/ejm-36-279-2024, https://doi.org/10.5194/ejm-36-279-2024, 2024
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We studied primary granitic and halogen-rich melt inclusions trapped in mantle rocks in the Bohemian Massif (Germany) in order to retrieve important information about the nature of the melt and the source rock. The melt was produced by the partial melting of metasediments during the deepest stages of subduction and interacted with the mantle. This work is an excellent example of transfer of crustal material, volatiles in particular, in the mantle during the subduction of the continental crust.
Gaston Godard, David C. Smith, Damien Jaujard, and Sidali Doukkari
Eur. J. Mineral., 36, 99–122, https://doi.org/10.5194/ejm-36-99-2024, https://doi.org/10.5194/ejm-36-99-2024, 2024
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Petrological and mineralogical studies of mica schists, orthogneisses and glaucophane eclogites from Dumet Island (Armorican Massif, NW France) indicate that this occurrence, which has undergone high-pressure metamorphism up to 16 kbar and 620 °C, is similar to that of Groix Island. There are about 10 similar occurrences within the Ibero-Armorican Arc, forming a discontinuous high-pressure belt, but most of them have remained unnoticed due to a high degree of retrogression.
Hafiz U. Rehman, Takanori Kagoshima, Naoto Takahata, Yuji Sano, Fabrice Barou, David Mainprice, and Hiroshi Yamamoto
Eur. J. Mineral., 35, 1079–1090, https://doi.org/10.5194/ejm-35-1079-2023, https://doi.org/10.5194/ejm-35-1079-2023, 2023
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Zircon preserves geologic rock history. Electron backscatter diffraction (EBSD) analysis is useful to visualize deformed domains in zircons. Zircons from the Himalayan high-pressure eclogites were analzyed for EBSD to identify intra-grain plastic deformation. The U–Pb isotope age dating, using Nano-SIMS, showed that plastic deformation likely affects the geochronological records. For geologically meaningful results, it is necessary to identify undisturbed domains in zircon via EBSD.
Silvio Ferrero, Alessia Borghini, Laurent Remusat, Gautier Nicoli, Bernd Wunder, and Roberto Braga
Eur. J. Mineral., 35, 1031–1049, https://doi.org/10.5194/ejm-35-1031-2023, https://doi.org/10.5194/ejm-35-1031-2023, 2023
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Garnet often entraps small droplets of deep melts generated during mountain building processes. Using high-resolution techniques, we studied these droplets in order to provide hard numbers for the quantification of volatile budgets during crustal evolution, show how even melts formed at >1000°C contain water, and clarify how water behaves during metamorphism and melting at the microscale. Moreover, we provide the very first data on chlorine in natural melts from crustal reworking.
Benoît Dubacq, Guillaume Bonnet, Manon Warembourg, and Benoît Baptiste
Eur. J. Mineral., 35, 831–844, https://doi.org/10.5194/ejm-35-831-2023, https://doi.org/10.5194/ejm-35-831-2023, 2023
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Minerals in a vein network from the Aravis limestone (Haute-Savoie, France) include carbonates, quartz, fluorite and phyllosilicates, crystallized at around 7 km depth and 190 °C. The mineralogy has been studied with emphasis on the chlorite types: chamosite (iron-rich), cookeite (lithium-rich) and sudoite. The presence of the three chlorite types sheds light on their phase diagrams, and observed cationic substitutions confirm the need for more systematic measurement of lithium in chlorite.
Simon Schorn, Anna Rogowitz, and Christoph A. Hauzenberger
Eur. J. Mineral., 35, 715–735, https://doi.org/10.5194/ejm-35-715-2023, https://doi.org/10.5194/ejm-35-715-2023, 2023
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We investigate rocks called eclogite, which are related to subduction and the collision of continents. Our samples show evidence of limited melting at high pressure corresponding to about 70 km depth, which may play an important role in the exhumation of these rocks and the differentiation of the crust. However, due to their composition and metamorphic evolution, melt production is limited, suggesting that similar rocks are unlikely to contribute strongly to subduction-related magmatism.
Thomas Gyomlai, Philippe Yamato, and Gaston Godard
Eur. J. Mineral., 35, 589–611, https://doi.org/10.5194/ejm-35-589-2023, https://doi.org/10.5194/ejm-35-589-2023, 2023
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The La Picherais metagranite is a key example of undeformed high-pressure quartzofeldspathic rock from the Armorican Massif. Through petrological observations and thermodynamic modelling, this study determines that the metagranite was pressured above 1.7 GPa and the associated mafic lenses at ~ 2.1 GPa. This metagranite provides an opportunity to study the degree of transformation of quartzofeldspathic rocks at high pressure, which may have a significant impact on the dynamics of subduction.
Pan Tang and Shun Guo
Eur. J. Mineral., 35, 569–588, https://doi.org/10.5194/ejm-35-569-2023, https://doi.org/10.5194/ejm-35-569-2023, 2023
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In this study, unusual corundum- and spinel-bearing symplectites after muscovite were found in ultrahigh-pressure eclogites from the Dabie terrane, China. The results indicate that these symplectites formed by the low-pressure partial melting of muscovite during slab exhumation. We stress that the occurrence of corundum- and spinel-bearing symplectites after muscovite in eclogites provides important implications for fluid and melt actions in exhumed slabs.
Michael Brown
Eur. J. Mineral., 35, 523–547, https://doi.org/10.5194/ejm-35-523-2023, https://doi.org/10.5194/ejm-35-523-2023, 2023
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The past 40 years have been a golden age for eclogite studies, supported by an ever wider range of instrumentation and enhanced computational capabilities, linked with ongoing developments in the determination of the temperatures and pressures of metamorphism and the age of these rocks. These data have been used to investigate the spatiotemporal distribution of metamorphism and secular change but not without controversy in relation to the emergence of plate tectonics on Earth.
Larry Tuttle and Darrell J. Henry
Eur. J. Mineral., 35, 499–522, https://doi.org/10.5194/ejm-35-499-2023, https://doi.org/10.5194/ejm-35-499-2023, 2023
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Quartz inclusions in garnet are used to constrain the metamorphic pressure–temperature history of multiple ~2.8 Ga metasedimentary rocks from Montana, USA. Inclusion studies along with mineral and whole rock chemistry suggests that the rocks of interest experienced a clockwise metamorphic P–T history that included isobaric heating to peak metamorphic temperatures once inclusions were entrapped. These findings place fundamental constraints on the P–T evolution of this important geologic setting.
Jan Schönig, Carsten Benner, Guido Meinhold, Hilmar von Eynatten, and N. Keno Lünsdorf
Eur. J. Mineral., 35, 479–498, https://doi.org/10.5194/ejm-35-479-2023, https://doi.org/10.5194/ejm-35-479-2023, 2023
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When and how modern-style plate tectonics initiated is a matter of debate. Although the earliest unequivocal evidence for ultrahigh-pressure metamorphism is Neoproterozoic, similar processes have been proposed for Paleoproterozoic rocks of western Greenland. We intensely screened the area by studying detrital heavy minerals, garnet chemistry, and mineral inclusion assemblages in garnet. Our results raise considerable doubts on the existence of Paleoproterozoic ultrahigh-pressure rocks.
Sara Nerone, Chiara Groppo, and Franco Rolfo
Eur. J. Mineral., 35, 305–320, https://doi.org/10.5194/ejm-35-305-2023, https://doi.org/10.5194/ejm-35-305-2023, 2023
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The coexistence of chloritoid and biotite in medium-pressure Barrovian terranes is uncommon, with chloritoid usually occurring at lower temperatures than biotite. A petrologic approach using equilibrium thermodynamic modelling points out how metapelites can attain H2O-undersaturated conditions even at medium pressure and amphibolite-facies conditions and consequently can be affected by kinetic barriers, which need to be taken into account.
Gerhard Franz, Martin Kutzschbach, Eleanor J. Berryman, Anette Meixner, Anselm Loges, and Dina Schultze
Eur. J. Mineral., 33, 401–423, https://doi.org/10.5194/ejm-33-401-2021, https://doi.org/10.5194/ejm-33-401-2021, 2021
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Metamorphic rocks contain information about their original rocks and thus provide insight into the earlier stages of a region of interest. Here, we used the whole-rock chemical composition and stable boron isotopes of a suite of rocks from the Alps (Italy–Austria), which were deposited in a restricted intramontane basin before the Alpine orogeny. It is possible to reconstruct the depositional conditions for these sediments, which are now common metamorphic rocks such as schists and gneisses.
Annette Süssenberger, Susanne Theodora Schmidt, Florian H. Schmidt, and Manuel F. G. Weinkauf
Eur. J. Mineral., 32, 653–671, https://doi.org/10.5194/ejm-32-653-2020, https://doi.org/10.5194/ejm-32-653-2020, 2020
Wentao Cao, Jane A. Gilotti, and Hans-Joachim Massonne
Eur. J. Mineral., 32, 405–425, https://doi.org/10.5194/ejm-32-405-2020, https://doi.org/10.5194/ejm-32-405-2020, 2020
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Zoisite eclogites from the Sanddal area, North-East Greenland, contain numerous textures, such as cusps and neoblasts, which are interpreted as melt-related textures. Mineral chemistry and thermodynamic modeling demonstrate that they were partially melted through the breakdown of hydrous minerals, phengite, paragonite and zoisite. Pressure–temperature phase diagrams show that the eclogites reached a maximum depth of ∼70 km and were partially melted near that depth and during exhumation.
Cited articles
Bakun-Czubarow, N.: Quartz pseudomorphs after coesite and quartz exsolutions in eclogitic ompjacites of the Złote Mountains in the Sudetes (SW Poland), Archiwum mineralogiczne, 48, 3–25, 1992. a
Bell, D. R. and Rossman, G. R.: Water in Earth's mantle: the role of nominally anhydrous minerals, Science, 255, 1391–1397, https://doi.org/10.1126/science.255.5050.1391, 1992. a
Bell, D. R., Rossman, G. R., and Moore, R. O.: Abundance and partitioning of OH in a high-pressure magmatic system: megacrysts from the Monastery kimberlite, South Africa, J. Petrol., 45, 1539–1564, https://doi.org/10.1093/petrology/egh015, 2004. a
Bose, K. and Ganguly, J.: Quartz-coesite transition revisited: reversed experimental determination at 500–1200 ∘C and retrieved thermochemical properties, Am. Mineral., 80, 231–238, 1995. a
Brown, M.: Metamorphic conditions in orogenic belts: a record of secular change, Int. Geol. Rev., 49, 193–234, https://doi.org/10.2747/0020-6814.49.3.193, 2007. a
Brueckner, H. K.: Sinking intrusion model for the emplacement of garnet-bearing peridotites into continent collision orogens, Geology, 26, 631–634, https://doi.org/10.1130/0091-7613(1998)026<0631:SIMFTE>2.3.CO;2, 1998. a
Brueckner, H. K., Carswell, D. A., and Griffin, W. L.: Paleozoic diamonds within a Precambrian peridotite lens in UHP gneisses of the Norwegian Caledonides, Earth Planet. Sc. Lett., 203, 805–816, 2002. a
Bruno, M., Compagnoni, R., Hirajima, T., and Rubbo, M.: Jadeite with the Ca-Eskola molecule from an ultra-high pressure metagranodiorite, Dora-Maira Massif, Western Alps, Contrib. Mineral. Petr., 142, 515–519, https://doi.org/10.1007/s004100100307, 2002. a
Carswell, D. A.: Garnet pyroxenite lens within Ugelvik layered garnet peridotite, Earth Planet. Sc. Lett., 20, 347–352, 1973. a
Carswell, D. A., Krogh, E. J., and Griffin, W. L.: Norwegion orthopyroxene eclogites: calculated equilibration conditions and petrogenetic implications, in: The Caledonide orogen – Scandinavia and related areas, edited by: Gee, D. G. and Sturt, B. A., 823–841, John Wiley & Sons, Chichester, ISBN: 0-471-90822-3, 1985. a, b
Carswell, D. A., Brueckner, H. K., Cuthbert, S. J., Mehta, K., and O'Brien, P. J.: The timing of stabilisation and the exhumation rate for ultra-high pressure rocks in the Western Gneiss Region of Norway, J. Metamorph. Geol., 21, 601–612, 2003a. a
Carswell, D. A., Tucker, R. D., O'Brien, P. J., and Krogh, T. E.: Coesite micro-inclusions and the U/Pb age of zircons from the Hareidland Eclogite in the Western Gneiss Region of Norway, Lithos, 67, 181–190, https://doi.org/10.1016/S0024-4937(03)00014-8, 2003b. a, b, c
Carswell, D. A., van Roermund, H. L. M., and Wiggers de Vries, D. F.: Scandian ultrahigh-pressure metamorphism of Proterozoic basement rocks on Fjørtoft and Otrøy, Western Gneiss Region, Norway, Int. Geol. Rev., 48, 957–977, https://doi.org/10.2747/0020-6814.48.11.957, 2006. a
Cherniak, D. J. and Dimanov, A.: Diffusion in pyroxene, mica and amphibole, Rev. Mineral. Geochem., 72, 641–690, https://doi.org/10.2138/rmg.2010.72.14, 2010. a
Cherniak, D. J. and Liang, Y.: Calcium diffusion in enstatite, with application to closure temperature of the Ca-in-opx thermometer, Geochim. Cosmochim. Ac., 332, 124–137, https://doi.org/10.1016/j.gca.2022.06.018, 2022. a
Chin, E. J., Lee, C.-T. A., and Blichert-Toft, J.: Growth of upper plate lithosphere controls tempo of arc magmatism: constraints from Al-diffusion kinetics and coupled Lu-Hf and Sm-Nd chronology, Geochemical Perspectives Letters, 1, 20–32, https://doi.org/10.7185/geochemlet.1503, 2015. a
Chopin, C.: Coesite and pure pyrope in high-grade blueschists of the Western Alps: a first record and some consequences, Contrib. Mineral. Petr., 86, 107–118, 1984. a
Coleman, R. G., Lee, D. E., Beatty, L. B., and Brannock, W. W.: Eclogites and eclogites: their differences and similarities, Geol. Soc. Am. Bull., 76, 483–508, https://doi.org/10.1130/0016-7606(1965)76[483:EAETDA]2.0.CO;2, 1965. a, b, c
Day, H. W.: A revised diamond-graphite transition curve, Am. Mineral., 97, 52–62, https://doi.org/10.2138/am.2011.3763, 2012. a
Dobretsov, N. L., Sobolev, N. V., Shatsky, V. S., Coleman, R. G., and Ernst, W. G.: Geotectonic evolution of diamondiferous paragneisses, Kokchetav Complex, northern Kazakhstan: The geologic enigma of ultrahigh-pressure crustal rocks within a Paleozoic foldbelt, Isl. Arc, 4, 267–279, https://doi.org/10.1111/j.1440-1738.1995.tb00149.x, 1995. a
Dobrzhinetskaya, L. F., Eide, E. A., Larsen, R. B., Sturt, B. A., Trønnes, R. G., Smith, D. C., Taylor, W. R., and Posukhova, T. V.: Microdiamond in high-grade metamorphic rocks from the Western Gneiss region, Norway, Geology, 23, 597–600, https://doi.org/10.1130/0091-7613(1995)023<0597:MIHGMR>2.3.CO;2, 1995. a
Dobrzhinetskaya, L. F., Green II, H. W., and Wang, S.: Alpe Arami: a peridotite massif from depth of more than 300 kilometers, Science, 271, 1841–1845, https://doi.org/10.1126/science.271.5257.1841, 1996. a
Duretz, T., Gerya, T. V., Kaus, B. J. P., and Andersen, T. B.: Thermomechanical modeling of slab eduction, J. Geophys. Res., 117, B08411, https://doi.org/10.1029/2012JB009137, 2012. a
Gasparik, T.: Phase Diagrams for Geoscientists – An Atlas of the Earth’s Interior, 2nd Edn., Springer, https://doi.org/10.1007/978-1-4614-5776-3, 2014. a
Gee, D. G., Kumpulainen, R., Roberts, D., Stephens, M. B., Thon, A., and Zachrisson, E.: Scandinavian Tectonostratigraphic Map, Sveriges Geologiska Undersökning Serie Ba, 1985. a
Gee, D. G., Janák, M., Majka, J., Robinson, P., and van Roermund, H.: Subduction along and within the Baltoscandian margin during closing of the Iapetus Ocean and Baltica-Laurentia collision, Lithosphere, 5, 169–178, https://doi.org/10.1130/L220.1, 2013. a
Gerya, T. V., Perchuk, L. L., and Burg, J.-P.: Transient hot channels: perpetrating and regurgitating ultrahigh-pressure, high-temperature crust–mantle associations in collision belts, Lithos, 103, 236–256, https://doi.org/10.1016/j.lithos.2007.09.017, 2008. a
Gose, J. and Schmädicke, E.: H2O in omphacite of quartz and coesite eclogite from Erzgebirge and Fichtelgebirge, Germany, J. Metamorph. Geol., 40, 665–686, https://doi.org/10.1111/jmg.12642, 2022. a
Griffin, W. L. and Brueckner, H. K.: Caledonian Sm-Nd ages and a crustal origin for Norwegian eclogites, Nature, 285, 319–321, 1980. a
Griffin, W. L., Jensen, B. B., and Misra, S. N.: Anomalously elongated rutile in eclogite-facies pyroxene and garnet, Norsk Geol. Tidsskr., 51, 177–185, 1971. a
Griffin, W. L., Austrheim, H., Brastad, K., Bryhni, I., Krill, A. G., Krogh, E. J., Mørk, M. B. E., Qvale, H., and Tørudbakken, B.: High-pressure metamorphism in the Scandinavian Caledonides, in: The Caledonide orogen – Scandinavia and related areas, edited by: Gee, D. G. and Sturt, B. A., 783–801, John Wiley & Sons, Chichester, ISBN: 0-471-90822-3, 1985. a
Grønlie, G., Mysen, B., and Bech, O. M.: Gravity investigation of the Hareidlandet eclogite, western Norway, Norsk Geol. Tidsskr., 52, 305–311, 1972. a
Grütter, H. S., Gurney, J. J., Menzies, A. H., and Winter, F.: An updated classification scheme for mantle-derived garnet, for use by diamond explorers, Lithos, 77, 841–857, https://doi.org/10.1016/j.lithos.2004.04.012, 2004. a
Hacker, B.: Ascent of the ultrahigh-presssure Western Gneiss Region, Norway, in: Convergent Margin Terranes and Associated Regions: A Tribute to W.G. Ernst, edited by: Cloos, M., Carlson, W. D., Gilbert, M. C., Liou, J. G., and Sorensen, S. S., Geological Society of America Special Paper 419, 171–184, Geological Society of America, https://doi.org/10.1130/2006.2419(09), 2007. a
Hacker, B. R., Andersen, T. B., Johnston, S., Kylander–Clark, A. R. C., Peterman, E. M., Walsh, E. O., and Young, D.: High-temperature deformation during continental-margin subduction & exhumation: the ultrahigh-pressure Western Gneiss Region of Norway, Tectonophysics, 480, 149–171, https://doi.org/10.1016/j.tecto.2009.08.012, 2010. a
Haggerty, S. E. and Sautter, V.: Ultradeep (greater than 300 kilometers), ultramafic upper mantle xenoliths, Science, 248, 993–996, https://doi.org/10.1126/science.248.4958.993, 1990. a
Hill, T. R., Konishi, H., Hobbs, F., Lee, S., and Xu, H.: Precipitates of α-cristobalite and silicate glass in UHP clinopyroxene from a Bohemian Massif eclogite, Am. Mineral., 104, 1402–1415, https://doi.org/10.2138/am-2019-6773, 2019. a
Hughes, L., Cuthbert, S., Quas-Cohen, A., Ruzié-Hamilton, L., Pawley, A., Droop, G., Lyon, I., Tartèse, R., and Burgess, R.: Halogens in eclogite facies minerals from the Western Gneiss Region, Norway, Minerals, 11, 760, https://doi.org/10.3390/min11070760, 2021. a
Knapp, N., Woodland, A. B., and Klimm, K.: Experimental constraints in the CMAS system on the Ca-Eskola content of eclogitic clinopyroxene, Eur. J. Mineral., 25, 579–596, https://doi.org/10.1127/0935-1221/2013/0025-2326, 2013. a
Konzett, J., Frost, D. J., Proyer, A., and Ulmer, P.: The Ca-Eskola component in eclogitic clinopyroxene as a function of pressure, temperature and bulk composition: an experimental study to 15 GPa with possible implications for the formation of oriented SiO2-inclusions in omphacite, Contrib. Mineral. Petr., 155, 215–228, https://doi.org/10.1007/s00410-007-0238-0, 2008. a
Krill, A. G.: Tectonics of the Oppdal area, central Norway, Geologiska Föreningen i Stockholm Förhandlingar, 102, 523–530, https://doi.org/10.1080/11035898009454505, 1980. a
Krogh, E. J.: Evidence of Precambrian continent–continent collision in Western Norway, Nature, 267, 17–19, https://doi.org/10.1038/267017a0, 1977. a
Kullerud, L., Tørudbakken, B. O., and Ilebekk, S.: A compilation of radiometric age determinations from the Western Gneiss Region, south Norway, Norg. Geol. Unders. B., 406, 17–42, 1986. a
Kylander-Clark, A. R. C., Hacker, B. R., Johnson, C. M., Beard, B. L., Mahlen, N. J., and Lapen, T. J.: Coupled Lu–Hf and Sm–Nd geochronology constrains prograde and exhumation histories of high- and ultrahigh-pressure eclogites from western Norway, Chem. Geol., 242, 137–154, https://doi.org/10.1016/j.chemgeo.2007.03.006, 2007. a
Kylander-Clark, A. R. C., Hacker, B. R., and Mattinson, C. G.: Size and exhumation rate of ultrahigh-pressure terranes linked to orogenic stage, Earth Planet. Sc. Lett., 321–322, 115–120, https://doi.org/10.1016/j.epsl.2011.12.036, 2012. a
Lafuente, B., Downs, R. T., Yang, H., and Stone, N.: The power of databases: The RRUFF project, in: Highlights in Mineralogical Crystallography, edited by: Armbruster, T. and Danisi, R. M., 1–29, De Gruyter, https://doi.org/10.1515/9783110417104-003, 2015. a, b, c
Lappin, M. A.: Eclogites from the Sunndal–Grubse ultramafic mass, Almklovdalen, Norway and the T–P history of the Almklovdalen masses, J. Petrol., 15, 567–601, https://doi.org/10.1093/petrology/15.3.567, 1974. a
Lappin, M. A. and Smith, D. C.: Carbonate, silicate and fluid relationships in eclogites, Selje district and environs, SW Norway, T. Roy. Soc. Edin.-Earth, 72, 171–193, https://doi.org/10.1017/S0263593300009986, 1981. a, b, c, d
Liu, P. and Massonne, H.-J.: An anticlockwise P–T–t path at high-pressure, high-temperature conditions for a migmatitic gneiss from the island of Fjørtoft, Western Gneiss Region, Norway, indicates two burial events during the Caledonian orogeny, J. Metamorph. Geol., 37, 567–588, https://doi.org/10.1111/jmg.12476, 2019. a
March, S., Hand, M., Tamblyn, R., Carvalho, B. B., and Clark, C.: A diachronous record of metamorphism in metapelites of the Western Gneiss Region, Norway, J. Metamorph. Geol., 40, 1121–1158, https://doi.org/10.1111/jmg.12660, 2022. a
Morimoto, N., Fabries, J., Ferguson, A. K., Ginzburg, I. V., Ross, M., Seifert, F. A., Zussman, J., Aoki, K., and Gottardi, G.: Nomenclature of pyroxenes, Am. Mineral., 73, 1123–1133, 1988. a
Mysen, B. O. and Heier, K. S.: Petrogenesis of eclogites in high grade metamorphic gneisses, exemplified by the Hareidland Eclogite, western Norway, Contrib. Mineral. Petr., 36, 73–94, 1972. a
Page, F. Z., Essene, E. J., and Mukasa, S. B.: Quartz exsolution in clinopyroxene is not proof of ultrahigh pressures: evidence from eclogites from the Eastern Blue Ridge, Southern Appalachians, U.S.A., Am. Mineral., 90, 1092–1099, https://doi.org/10.2138/am.2005.1761, 2005. a, b
Pearson, D. G., Canil, D., and Shirey, S. B.: Mantle samples included in volcanic rocks: xenoliths and diamonds, in Treatise on Geochemistry, Volume 2: The Core and Mantle, edited by: Holland, H. D., and Turekian, K. K., 171–275, Elsevier, Oxford, https://doi.org/10.1016/B0-08-043751-6/02005-3, 2003. a
Quas-Cohen, A.: Norwegian orthopyroxene eclogites: petrogenesis and implications for metasomatism and crust-mantle interactions during subduction of continental crust, PhD thesis, University of Manchester, https://research.manchester.ac.uk/en/ (last access: 20 October 2020), 2014. a, b
Robinson, P., Terry, M. P., Carswell, T., Van Roermund, H., Krogh, T. E., Root, D., Tucker, R. D., and Solli, A.: Tectono-stratigraphic setting, structure and petrology of HP and UHP metamorphic rocks and garnet peridotites in the Western Gneiss Region, Møre and Romsdal, Norway, Tech. Rep. report no: 2003.057, Norges geologiske undersøkelse, Trondheim, Alice Wain Memorial West Norway Eclogite Field Symposium, guidebook for post-meeting field excursion, 2003. a
Root, D. B., Hacker, B. R., Gans, P. B., Ducea, M. N., Eide, E. A., and Mosenfelder, J. L.: Discrete ultrahigh-pressure domains in the Western Gneiss Region, Norway: implications for formation and exhumation, J. Metamorph. Geol., 23, 45–61, https://doi.org/10.1111/j.1525-1314.2005.00561.x, 2005. a
Schmidt, M. W. and Poli, S.: Experimentally based water budgets for dehydrating slabs and consequences for arc magma generation, Earth Planet. Sc. Lett., 163, 361–379, 1998. a
Schmädicke, E. and Müller, W. F.: Unusual exsolution phenomena in omphacite and partial replacement of phengite by phlogopite + kyanite in an eclogite from the Erzgebirge, Contrib. Mineral. Petr., 139, 629–642, https://doi.org/10.1007/s004100000161, 2000. a, b, c, d
Schönig, J., Meinhold, G., von Eynatten, H., and Lünsdorf, N. K.: Tracing ultrahigh-pressure metamorphism at the catchment scale, Sci. Rep., 8, 2931, https://doi.org/10.1038/s41598-018-21262-8, 2018. a
Schroeder-Frerkes, F., Woodland, A. B., Uenver-Thiele, L., Klimm, K., and Knapp, N.: Ca-Eskola incorporation in clinopyroxene: limitations and petrological implications for eclogites and related rocks, Contrib. Mineral. Petr., 171, 101, https://doi.org/10.1007/s00410-016-1311-3, 2016. a
Shatsky, V. S., Sobolev, N. V., and Stenina, N. G.: Structural peculiarities of pyroxenes from eclogites, Terra Cognita, 5, 436–437, 1985. a
Skogby, H., Janák, M., and Broska, I.: Water incorporation in omphacite: concentrations and compositional relations in ultrahigh-pressure eclogites from Pohorje, Eastern Alps, Eur. J. Mineral., 28, 631–639, https://doi.org/10.1127/ejm/2016/0028-2533, 2016. a
Smith, D. C.: Coesite in clinopyroxene in the Caledonides and its implications for geodynamics, Nature, 310, 641–644, https://doi.org/10.1038/310641a0, 1984. a, b, c
Smith, D. C.: A review of the peculiar mineralogy of the “Norwegian coesite-eclogite province” with crystal-chemical, petrological, geochemical and geodynamical notes and an extensive bibliography, in: Eclogites and Eclogite-facies Rocks, edited by: Smith, D. C., 1–206, Elsevier, ISBN: 044443030X, 1988. a, b
Smith, D. C. and Cheeney, R. F.: Orientated needles of quartz in clinopyroxene: evidence for exsolution of SiO2 from a non-stoichiometric supersilicic “clinopyroxene”, in: 26th International Geological Congress, Paris, 02.3.1, 145, Abstracts, 7–17 July 1980, 1980. a
Smith, D. C. and Lappin, M. A.: Coesite in the Staumen kyanite-eclogite pod, Norway, Terra Nova, 1, 47–56, https://doi.org/10.1111/j.1365-3121.1989.tb00325.x, 1989. a
Smyth, J. R., Bell, D. R., and Rossman, G. R.: Incorporation of hydroxyl in upper-mantle clinopyroxenes, Nature, 351, 732–735, https://doi.org/10.1038/351732a0, 1991. a
Spencer, K. J., Hacker, B. R., Kylander-Clark, A. R. C., Andersen, T. B., Cottle, J. M., Stearns, M. A., Poletti, J. E., and Seward, G. G. E.: Campaign-style titanite U–Pb dating by laser-ablation ICP: implications for crustal flow, phase transformations and titanite closure, Chem. Geol., 341, 84–101, https://doi.org/10.1016/j.chemgeo.2012.11.012, 2013. a
Spengler, D., Brueckner, H. K., van Roermund, H. L. M., Drury, M. R., and Mason, P. R. D.: Long-lived, cold burial of Baltica to 200 km depth, Earth Planet. Sc. Lett, 281, 27–35, https://doi.org/10.1016/j.epsl.2009.02.001, 2009. a, b, c
Terry, M. P. and Heidelbach, F.: Deformation-enhanced metamorphic reactions and the rheology of high-pressure shear zones, Western Gneiss Region, Norway, J. Metamorph. Geol., 24, 3–18, https://doi.org/10.1111/j.1525-1314.2005.00618.x, 2006. a
Terry, M. P., Bromiley, G. D., Robinson, P., and Heidelbach, F.: Determination of equilibrium water content and composition of omphacitic pyroxene in an UHP kyanite-eclogite, Western Norway, 6–11 April 2003, Nice, France, Geophys. Res. Abstr., 5, 08698, 2003. a
Tucker, R. D., Krogh, T. E., and Råheim, A.: Proterozoic evolution and age-province boundaries in the central part of the Western Gneiss Region, Norway: results of U-Pb dating of accessory minerals from Trondheimsfjord to Geiranger, Special Paper 38, 149–173, Geological Association of Canada, 1990. a
Tucker, R. D., Robinson, P., Solli, A., Gee, D. G., Thorsnes, T., Krogh, T. E., Nordgulen, Ø., and Bickford, M. E.: Thrusting and extension in the Scandian hinterland, Norway: new U-Pb ages and tectonostratigraphic evidence, Am. J. Sci., 304, 477–532, https://doi.org/10.2475/ajs.304.6.477, 2004. a
van Roermund, H. L. M., Carswell, D. A., Drury, M. R., and Heijboer, T. C.: Microdiamonds in a megacrystic garnet websterite pod from Bardane on the island of Fjørtoft, western Norway: evidence for diamond formation in mantle rocks during deep continental subduction, Geology, 30, 959–962, https://doi.org/10.1130/0091-7613(2002)030<0959:MIAMGW>2.0.CO;2, 2002. a
Vrijmoed, J. C., van Roermund, H. L. M., and Davies, G. R.: Evidence for diamond-grade ultra-high pressure metamorphism and fluid interaction in the Svartberget Fe–Ti garnet peridotite–websterite body, Western Gneiss Region, Norway, Mineral. Petr., 88, 381–405, https://doi.org/10.1007/s00710-006-0160-6, 2006. a
Vrijmoed, J. C., Smith, D. C., and van Roermund, H. L. M.: Raman confirmation of microdiamond in the Svartberget Fe-Ti type garnet peridotite, Western Gneiss Region, Western Norway, Terra Nova, 20, 295–301, https://doi.org/10.1111/j.1365-3121.2008.00820.x, 2008. a
Vrijmoed, J. C., Austrheim, H., John, T., Hin, R. C., Corfu, F., and Davies, G. R.: Metasomatism in the ultrahigh-pressure Svartberget garnet-peridotite (Western Gneiss Region, Norway): implications for the transport of crust-derived fluids within the mantle, J. Petrol., 54, 1815–1848, https://doi.org/10.1093/petrology/egt032, 2013. a
Wain, A.: New evidence for coesite in eclogite and gneisses: defining an ultrahigh-pressure province in the Western Gneiss region of Norway, Geology, 25, 927–930, https://doi.org/10.1130/0091-7613(1997)025<0927:NEFCIE>2.3.CO;2, 1997. a
Wain, A., Waters, D., Jephcoat, A., and Olijynk, H.: The high-pressure to ultrahigh-pressure eclogite transition in the Western Gneiss Region, Norway, Eur. J. Mineral., 12, 667–687, https://doi.org/10.1127/0935-1221/2000/0012-0667, 2000. a, b
Walczak, K., Cuthbert, S., Kooijman, E., Majka, J., and Smit, M. A.: U–Pb zircon age dating of diamond-bearing gneiss from Fjørtoft reveals repeated burial of the Baltoscandian margin during the Caledonian Orogeny, Geol. Mag., 156, 1949–1964, https://doi.org/10.1017/S0016756819000268, 2019. a
Warren, C. J., Beaumont, C., and Jamieson, R. A.: Deep subduction and rapid exhumation: role of crustal strength and strain weakening in continental subduction and ultrahigh-pressure rock exhumation, Tectonics, 27, TC6002, https://doi.org/10.1029/2008TC002292, 2008. a
Yamato, P., Burov, E., Agard, P., Pourhiet, L. L., and Jolivet, L.: HP-UHP exhumation during slow continental subduction: self-consistent thermodynamically and thermomechanically coupled model with application to the Western Alps, Earth Planet. Sc. Lett., 271, 63–74, https://doi.org/10.1016/j.epsl.2008.03.049, 2008. a
Young, D. J.: Structure of the (ultra)high-pressure Western Gneiss Region, Norway: imbrication during Caledonian continental margin subduction, GSA Bulletin, 130, 926–940, https://doi.org/10.1130/B31764.1, 2018. a
Young, D. J., Hacker, B. R., Andersen, T. B., and Corfu, F.: Prograde amphibolite facies to ultrahigh-pressure transition along Nordfjord, western Norway: implications for exhumation tectonics, Tectonics, 26, TC1007, https://doi.org/10.1029/2004TC001781, 2007. a
Zhang, L., Song, S., Liou, J. G., Ai, Y., and Li, X.: Relict coesite exsolution in omphacite from western Tianshan eclogites, China, Am. Mineral., 90, 181–186, https://doi.org/10.2138/am.2005.1587, 2005. a
Short summary
Rock lenses from the diamond stability field (>120 km depth) within ordinary gneiss are enigmatic. Even more when these lenses form an alternating exposure pattern with ordinary lenses. We studied 10 lenses from W Norway and found that many of them have a hidden history. Tiny needles of quartz enclosed in old pyroxene cores are evidence for a rock origin at great depth. These needles survived the rocks' passage to the surface that variably obscured the mineral chemistry – the rocks' memory.
Rock lenses from the diamond stability field (>120 km depth) within ordinary gneiss are...