Milovanovi Dragan Eric Suzana Seke Lajos Petrology and

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Milovanović Dragan. , Eric Suzana. , Seke Lajos. Petrology and metamorphism of amphibolites with

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

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

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

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

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

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

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

Mineral composition Rock composition Corundum contain 0. 085 -0. 161% Cr 2 O 3 Corundum

Rock composition

Rock composition

Degrees of metamorphism P (kbar) Experimental constraints S&D 94 Amphibole - plagioclase Qtz-absent Grt

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

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

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

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

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

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.