 | Groppo, Chiara, Ferrando, Simona, Gilio, Manuele, Botta, Serena, Nosenzo, Francesco, Balestro, Gianni, Festa, Andrea, Rolfo, Franco (2019) What’s in the sandwich? New P–T constraints for the (U)HP nappe stack of southern Dora-Maira Massif (Western Alps) European Journal of Mineralogy, 31 (4) 665-683 doi:10.1127/ejm/2019/0031-2860 | Journal (article/letter/editorial) | | constraints for the (U)HP nappe stack of southern Dora-Maira Massif (Western Alps) Chiara GROPPO1,2,*, Simona...of Torino, Via Valperga Caluso 35, 10125 Torino, Italy *Corresponding author, e-mail: chiara.groppo@unito...10125 Torino, Italy Abstract: The Brossasco-Isasca Unit (BIU) of the southern Dora-Maira Massif (DMM)...literature as a tectonic “sandwich”, with the UHP unit in the middle, bounded by two high-pressure (HP)...footwall (the San Chiaffredo Unit, SCU) and hanging wall (the Rocca Solei Unit, RSU), respectively. These |  | | Journal (article/letter/editorial) | | fractionation in the coesite-bearing ‘pyrope quartzite’ and related rocks of the Dora-Maira Massif, Western...ultrahigh-pressure (UHP) metamorphic rocks from the Dora-Maira Massif as well as of their granitic country rocks...the retrograde breakdown of pyrope to a chlorite-bearing assemblage, these elements became mobilized and...the leucophyllite samples as well. Key-words: Dora-Maira, ‘pyrope quartzite’, whiteschist, UHP, mobility...Introduction located in the southern part of the Dora-Maira Massif, Western Alps (e.g., Chopin, 1984; Chopin |  | Solarino, Stefano, Malusà, Marco G., Eva, Elena, Guillot, Stéphane, Paul, Anne, Schwartz, Stéphane, Zhao, Liang, Aubert, Coralie, Dumont, Thierry, Pondrelli, Silvia, Salimbeni, Simone, Wang, Qingchen, Xu, Xiaobing, Zheng, Tianyu, Zhu, Rixiang (2018) Mantle wedge exhumation beneath the Dora-Maira (U)HP dome unravelled by local earthquake tomography (Western Alps) Lithos, 296. 623-636 doi:10.1016/j.lithos.2017.11.035 | Journal (article/letter/editorial) | | Manuscript Mantle wedge exhumation beneath the Dora-Maira (U)HP dome unravelled by local earthquake tomography...Rixiang Zhu , Mantle wedge exhumation beneath the Dora-Maira (U)HP dome unravelled by local earthquake tomography...MANUSCRIPT Mantle wedge exhumation beneath the Dora-Maira (U)HP dome unravelled by local earthquake tomography...Nazionale di Geofisica e Vulcanologia, CNT, Genova, Italy 2 Department of Earth and Environmental Sciences...Sciences, University of Milano-Bicocca, Milano, Italy 3 Univ. Grenoble Alpes, Univ. Savoie Mont-Blanc, CNRS |  | | Journal (article/letter/editorial) | | The metamorphic and deformational history of coesite-bearing, ultrahigh-pressure metamorphic oceanic crust...of more than 80 km, in the stability field of coesite. The deformation was progressively localised into...‘classical’ area of UHPM continental crust in the Dora Maira Massif, western Alps. In that area, the U-Pb...for Dabie Shan by Hacker et al. (1995) and for Dora Maira by Wheeler (1991), Henry et al. (1993) and Michard...Valtoumanche, the western Alps of 41 (1997) 79-102 Italy (Reinecke, 1991; Reinecke et al., 1994). The structural |  | | Journal (article/letter/editorial) | | isotope data from garnets in ultrahigh-pressure (coesite-bearing) eclogite from the Western Alps were obtained...rocks will not be well constrained. Dating garnet-bearing eclogites traditionally has 0012-821X/99/$ - see...T~sch (2) also shown. method to the coesite-bearing eclogite unit at Lago di Cignana (Fig. 1). The high-precision...present throughout the Valtournanche, northern Italy ([15,16], and our mapping). Both the serpentinite...quartzites and metapelites [17], some of which contain coesite [18]. This protolith sequence is preserved more |  | | Journal (article/letter/editorial) | | southern Urals contains a regionally coherent crustal unit that experienced peak metamorphic conditions of...C at 378 6 Ma. Exhumation of the high-pressure unit occurred under retrograde blueschist and middle/lower...during decompression. The rise of the high-pressure unit to a mid-crustal depth ( 20 km) was accommodated...histories (Lennykh 1977; Lennykh et al. 1995). The lower unit 1 has been interpreted as subducted continental...of the East European platform, whereas the upper unit 2 is thought to represent Palaeozoic oceanic crust |  | | Report (chapter) | | units. The allochthonous unit is composed of UHP rocks. The parautochthonous unit is represented by the...autochthonous unit includes Jurassic and Cretaceous sedimentary and igneous rocks. The reworked unit is characterized...the subducted continental materials. If the UHP unit is the piston to build up the orogenic belt, then...the UHP terranes. Although the first report of coesite from China (Xu, Z. 1987) was made three years later...Europe (Chopin 1984; Smith 1984), the Chinese coesite has attracted world-wide attention since the very |  | | Journal (article/letter/editorial) | | Thus, the Briançonnais may be seen as a continental unit Downloaded by [Columbia University] at 10:27 14... high-pressure rocks situated within the Valais unit in the Versoyen area (Fig. 1) may be interpreted...Eiermann, 1988). In the Central Alps, the Valais unit is present in the Misox zone between the Tambo nappe... 1), and in the Western Alps by parts of the Dora Maira (Philippot, 1990; Chopin et al., 1991; Henry...facies. In places, metatuffs and MORB-type (garnet-bearing) greenschists, locally with relics of pillow structures |  | | Journal (article/letter/editorial) | | the SinoKorean and Yangtse cratons ŽFig. 1.. Coesite-bearing rocks Žmainly eclogites. are widely distributed...used to constrain Ž1. the petrogenesis of the coesite-bearing eclogites and associated ultramafic rocks,...the north by a greenschist facies meta-sedimentary unit, the Foziling Group, which is composed of several...high modal abundance of plagioclase and accessory apatite and Notes to Table 1: Ž1. Major and trace elements...biotite, and minor ilmenite, magnetite, and trace apatite. Petrographic description is given in Appendix |  | | Report (issue) | | on the inference of thermal history models from apatite fission-track data—A synthetic data study. . ....on detrital sediments: The Tertiary Piedmont Basin, northwest Italy . . . . . . . . . . . . . . . . . ...white mica 40Ar-39Ar analysis, using the Tertiary Piedmont basin and the eroding Western and Ligurian Alps...resolution of thermal histories from detrital apatite fission-track data. This is done on a set of synthetic...fissiontrack analysis of apatite and zircon, and more recently (U-Th)/He dating of apatite and zircon. While |  | | Report (chapter) | | ultra high-pressure (UHP) metamorphism in the Dora Maira massif has now taken place and of the age of... this time involving UHP metamorphism in the Dora Maira massif. These rocks were then rapidly exhumed...rapid extension in the southern Basin and Range province took place at c. 22-21 Ma (Foster & John 1999)...that the 'syn-greenschist decompression of the Dora Maira pile can be interpreted as the result of the...with widespread formation of omphacite-jadeite bearing eclogite-facies rocks. Note also that most garnet |  | Shi, Guanghai, Lei, Weiyan, He, Huaiyu, Ng, Yi Nok, Liu, Yan, Liu, Yingxin, Yuan, Ye, Kang, Zhijuan, Xie, Gen (2014) Superimposed tectono-metamorphic episodes of Jurassic and Eocene age in the jadeite uplift, Myanmar, as revealed by 40Ar/39Ar dating. Gondwana Research, 26 (2) 464-474 doi:10.1016/j.gr.2013.08.007 | Journal (article/letter/editorial) | | uplift (“jadeite uplift” consists of jadeitite-bearing serpentinite mélange and other metamorphic units)...glaucophanebearing quartz-schist and phengitic muscovite-bearing quartz-schists that may have correlation with the...muscovite-bearing glaucophane-schist, stilpnomelane-bearing quartzite, phengitic muscovite-bearing quartz-schist...quartz-schist, garnet-bearing amphibolite and diopside-bearing marble occur (Bender, 1983; Shi et al., 2001)...metasomatic 3 aggregates of kosmochlor, Cr-bearing jadeite, Cr-bearing omphacite and jadeitized rodingite (Shi |  | | Journal (article/letter/editorial) | | in this paper, refers to the blueschist-facies-bearing orogenic belt, which often includes many other...stabilities of diamond-graphite (Bundy, 1980), coesite-quartz (Bohlen and Boettcher, 1982), jadeite +...aragonite-bearing rocks often appear in the circum-Pacific and the Tethyan orogenic belts. Coesite- and (rarely)...(rarely) diamond-bearing metamorphic rocks are exposed within tectonic collages formed by continental-collision...metamorphism. The P / T estimate of glaucophane-bearing rocks is about 450° C and 9 kbar (Laird and Albee |  | ZHANG, R. Y., LIOU, J. G., OMORI, S., SOBOLEV, N. V., SHATSKY, V. S., IIZUKA, Y., LO, C.-H., OGASAWARA, Y. (2012) Tale of the Kulet eclogite from the Kokchetav Massive, Kazakhstan: Initial tectonic setting and transition from amphibolite to eclogite. Journal of Metamorphic Geology, 30 (5) 537-559 doi:10.1111/j.1525-1314.2012.00980.x | Journal (article/letter/editorial) | | INTRODUCTION The Kokchetav Massif [a diamond-bearing ultrahighpressure (UHP) metamorphic terrane], Kazakhstan...Most past studies focused on the western, diamond-bearing, part of the Kokchetav massif, and 2012 Blackwell...(Zhang et al., 1997), but it was the discovery of coesite in garnet from a pelitic schist (Shatsky et al...that confirmed UHP metamorphism in the Kulet area (unit II). Apart from a few dark-coloured eclogite bodies...650–750 C and 27–32 kbar, some bodies are in coesite eclogite zone, and others are in quartz eclogite |  | | Report (volume) | | Society from: The Geological Society Publishing House Unit 7, Brassmill Enterprise Centre Brassmill Lane Bath...are present, particularly in the secondary load-bearing region of the mid-crust (Fig. 2), these will preferentially...Proterozoic in age. In contrast, the Basin and Range Province of the western US, for example, demonstrates extensive...(Smith 1984; Chopin 1987; Wang et al 1989) contain coesite, implying that continental crust has been buried...(CEFT). They should be distinguished from eclogite bearing terranes formed within subduction zone complexes |  | | Report (volume) | | Society from: The Geological Society Publishing House Unit 7, Brassmill Enterprise Centre Brassmill Lane Bath...in China: a case-study from Wutaishan, Shanxi Province, demonstrating the application of precise SHRIMP...subducted to > 150 km, creating the diamondand coesite-bearing eclogitic rocks of Dabie-Sulu. These are rocks...in China: a case-study from Wutaishan, Shanxi Province, demonstrating the application of precise SHRIMP...Traditional subdivision of the Wutai 'Group' of Shanxi province, based on Tian (1991) and Ma & Bai (1998). The |  | | Report (volume) | | Society from: The Geological Society Publishing House Unit 7, Brassmill Enterprise Centre Brassmill Lane Bath...faults within the Colfiorito fault system (central Italy) AUSTIN, N. J. & KENNEDY,L. A. Textural controls...subduction and exhumation: an example from the Ulten Unit, Tonale Nappe, Eastern Austroalpine 159 RAIMBOURG...locality near Sestri Levante in the Liguride units, Italy (see hammer for scale). model also allows the introduction...faults within the Colfiorito fault system (central Italy) F. M I R A B E L L A , V. B O C C A L I & M. R |
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