Milovanovi Dragan Eric Suzana Seke Lajos Petrology and
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Milovanović Dragan. , Eric Suzana. , Seke Lajos. Petrology and metamorphism of amphibolites with corundum from Prijepolje , Dinaridic ophiolite Belt (Southwestern Serbia)
Geographic position of Serbia on Balkan Peninsula K A R P A T H O S K I A D A R D E D I N P E S A S L P A L B A E N I N E S
The Mesozoic ophiolites in Serbia TISSIA Va rd ar Belgrade zo ne Jadar block Va rda rz on e r e lt be zon lite hio op rda Va e rid na Di Amphibolites with corundum Drina Ivanjica terran
The Mesozoic ophiolites in Serbia TISSIA Va Pillow lavas rd ar Belgrade zo Tr ias sic ne Jadar block Va rda r z peridotites Zlatibor on e Triassic limestone rda Va r lt be e te zon oti rid te Pe i iol ph eo rid na ites m Di ol du ib un ph or m c A ith w Amphibolites with corundum s O ph io lit ic m el an ge lim es to ne Drina Ivanjica terran
The field trip observations Ø Amphibolite with corundum occur as lens, up to 100 m. thick Øtectonic contact with surroundig rocks, peridotites and mafic granulites Amphibilite with corundum Fault Peridotites with Gr-Cpi veins 500 m Mafic granulite Fault
The field trip observations Mineral composition Ø Amphibolite with corundum occur as lens, up to 100 m. thick Øtectonic contact with surroundig rocks, peridotites and mafic granulites
Mineral composition Plagioclase with 92. 9 -98. 9% An (average 95. 18) Piroxene Plagioclase Amphibole
Mineral composition Rock composition Corundum contain 0. 085 -0. 161% Cr 2 O 3 Corundum
Rock composition
Degrees of metamorphism P (kbar) Experimental constraints S&D 94 Amphibole - plagioclase Qtz-absent Grt Qtz-present geothermometer Hbl 16 Cpx Pl Qtz L (Blundy and Cpx 1990) Qtz Holland, Hbl W&N 91 R 93 P&B 95 Grt 0 Pl C 8 -12 k. B, C 88820 -1050 Opx Pl Qtz L V 12 E&T 86 R 91 Al content in Ho (N&C Hammerstorm and 8 N&C 00 00 Zen, 1986) PJ 7868, and Hbl Opx W&W 94 b a WW 93 4 Pl Qtz P&B 95 6 -12 k. BB&L 91 Hbl+Qtz= Opx+Cpx+Pl+V 0 400 Cpx L B 69 S 81 CWT 67 600 800 1000 T (0 C)
Degrees of metamorphism The genesis of Corundum: As a residue after partial melting as one of the liquides phases, with clinopyroxene and spinel or clinopyroxene and garnet for gabbroic anorthosite (Raheim&Green, 1974) Metamorphic origin by reaction spinel+anorthite = corundum+diopside in rocks with sufficiently high Al 2 O 3 content, e. g. a troctolitic protholith This reaction needs spinel as one of the reactants, which may be formed by the raction olivine + plagioclase = orthopyroxene + clinopyroxene + spinel. (Kushiro&Yoder, 1966) The maximum P-T condition still remains open. The most common mineral assemblage in the upper amphibolite facies for metabasites is Hbl+Pl±Qtz, with or without either Cpx or garnet. Replacement of Hbl+Pl±Qtz by combinations of Cpx, Pl + corundum is the main task of this study.
Protolith Subduction ? Eu and Sr positive anomalies reflect plagioclase accumulation, protolith have a cumulus origin (olivine gabbro ? ) High Cr content (783 -1090 ppm) imply formation from not evolved liquids. Whole-rock and mineral chemical compositions of Am. C have cumulus origin, with a primary (? ) mineral assemblage controlled by crystalization of olivine, plagioclase and clinopyroxene, as residue from primitive mantle (MORB source mantle ? ).
Protolith Eu and Sr positive anomalies reflect plagioclase accumulation, protolith have a cumulus origin (olivine gabbro ? ) High Cr content (783 -1090 ppm) imply formation from not evolved liquids. Whole-rock and mineral chemical compositions of Am. C have cumulus origin, with a primary (? ) mineral assemblage controlled by crystalization of olivine, plagioclase and clinopyroxene, as residue from primitive mantle (MORB source mantle ? ).
Conclusions: Whole rock compositions, with positive Eu and Sr anomalies indicate that protoliths of Amc have a basic composition, olivine gabbro cumulates (? ) After cooling at shallow levels olivin gabbro cumulates , together with surrounding peridotites undergone subduction and metamorphose under amphibole-granuliteeclogite facies, most probably related with Jurassic subduction during formation of Dinaridic ophiolite belt. During uplift and tectonical emplacement (closing of ocean space) the Am. C was dismembered, forming fragments which were included in the ophiolite melange. The absence of thermal relaxation features in Amc require rapid exhumation. Amphibilite with corundum Peridotites with Gr-Cpi veins Mafic granulites
Conclusions: Ophiolites in Serbia and surrounding countries one ar z t Vard bel lite hio op Di na rid ic Degrees of metamorphism of Am. C and relation with ultramafic rocks is one of the important questions in genesis and emplacement of Dinaridic ophiolite belt.