Arc-related to post-collisional magmatism at Serra dos

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Arc-related to post-collisional magmatism at Serra dos Órgãos region, Rio de Janeiro State, Brazil: products of Gondwana assembly, during the Brasiliano-Pan African Orogeny During Congress Field Trip, august 12-13, 2000 31 International Geological Congress Rio de Janeiro, Brazil Field trip leader: Miguel Tupinambá 1 Associate leaders: Hélio Monteiro Penha 2, Maria do Carmo Bustamante Junho 2 1

Tektos – Geotectonic research group, Faculty of Geology, Rio de Janeiro State University (UERJ) Rua São Francisco Xavier, 524, sala A4006. Maracanã. Rio de Janeiro RJ BRAZIL CEP 20559-900 Phone Number: 55 021 587-7102; Telefax 55 021 587-7704 E-mail: [email protected] 2

Departamento de Geologia, IGEO – Rio de Janeiro Federal University (UFRJ) Av. Marechal Tropowski, s/no Cidade Universitária, Ilha do Fundão. Rio de Janeiro RJ BRAZIL Phone Number: 55 021 598-9464, 598-9463; telefax 55 021 598-9465 E-mail: [email protected]

See also at 31 IGC Gen. Symp. 9-3: Tectonic Evolution of Proterozoic Orogenic Belts, monday 14, 13:00/17:00: Almeida, J.C.H. et al., Structural framework of the Central Ribeira Belt – M45 Heilbron, M. et al.,Tectonic map of the Central Ribeira Belt – M37 Heilbron, M. et al.,Comprehensive tectonic model for the Neoprotoerozoic Ribeira Orogenic Belt, SE BR – M48 Tupinambá, M. et al., Magmatic record of subduction, continental collision and tectonic collapse during western Gondwana assembly at the Oriental Terrane of the Ribeira Belt (SE Brazil) -- M55 During Congress Workshop 01: Foreland Basins of the Neoproterozoic Belts in Central to Souther Africa and South America: geotectonic evolution and mineral resources (IGCP-419), august 9-10.

Acknowledgements Universidade do Estado do Rio de Janeiro; Pedreira de Araras Ltda.; Pedreira S. A. dos Santos; BetonBras Ltda.; Sociedade Empreiteira de Terraplenagem e Engenharia Ltda.; A. F. Capelle & Cia. Ltda

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ABSTRACT Serra dos Órgãos is the local name for the 1.000 km-long mountain range that extends along the brazilian atlantic coast, generically called Serra do Mar. The formation of relief is related to the Gondwana break-up, which began at Middle Cretaceous, with a strong increment at the Early Tertiary. At the Rio de Janeiro State, topograhy is marked by a series of granitic peaks, and the topographic profile resembles the tubes of the old organs -- that’s why it is called Serra dos Órgãos, a portuguese name for organs. The geological framework is: a) tonalitic to granodioritic orthogneisses, quartz-dioritic and gabbroic stocks that comprise the Rio Negro Complex, a pre-collisional (640-600 Ma) magmatism; b) weakly peraluminous leucogranitic gneisses generated during the main phase of continent/arc collision (620-590 Ma); c) a megasheet of granodioritic to granitic orthogneiss (Serra dos Órgãos Batholith) represents the late-tectonic (580-540 Ma) magmatism; d) post-collisional granites (540 to 480 Ma) cut all the gneisses and are located at the highest peaks of the mountain range. All plutonic rocks were formed during the Brasiliano-Panafrican orogeny, and are related to the Gondwana assembly at the end of the Proterozoic.. The long-term uplift of the orogen during the Phanerozoic now exposes the deep section of the plutonic arc. During the field trip, the group will visit outcrops showing temporal and tectonic relationships between plutonic rocks. Petrographic and litogeochemical characteristics from the rocks will also be described. The towns visited along the trip (Teresópolis and Petrópolis) have some interesting cultural and historical features. They were founded in the 18th century by Pedro II, emperor of the Brasil, Portugal and Algarve Empire (that ended on 1822) and have some castles and churches from this epoch. INTRODUCTION The São Francisco/West Congo Craton is surrounded by Brasiliano/Pan-African belts (720-550 Ma) that evolved during the agglutination of the Gondwana Supercontinent. The Ribeira Belt (Almeida et al. 1973), one of these belts, lies along the Brazilian Atlantic Coast (Fig. 1). During the field trip, the group will visit outcrops showing temporal and tectonic relationships between plutonic rocks of the Ribeira Belt Oriental Terrane. Petrographic and litogeochemical characteristics from the rocks will also be discussed. TECTONIC SETTING The major tectonic framework of the Ribeira Belt (Figs. 1, 6) is defined by two distinct terranes (Heilbron et al.. 2000). The Occidental Terrane comprises a pile of superposed allochtonous terranes thrusted to the west (Heilbron et al. 1995) and subsequently deformed in transpressional regime, with large vertical oblique shear zones associated with granitic plutons (Ebert et al. 1991). It is considered as the early São Francisco Craton passive margin (Heilbron et al. 2000). The Oriental Terrane (or Costeiro Domain, Machado et al. 1996; Serra do Mar Microplate, Campos Neto & Figueiredo 1995) is characterized by large isoclinal recumbent folds, low angle dipping metamorphic foliation, and numerous NW trending ductile-ruptile shear zones containing post-collisional granitoids (Tupinambá 1999). In the central segment of the Ribeira Belt (Fig. 1), the western edge of the Oriental Terrane is marked by a moderate northwest dipping (~35o) shear zone -- the Central Tectonic Boundary (Almeida et al. 1998). The Oriental Terrane was divided by Heilbron et al. (2000)

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into three tectono-magmatic domains: the Rio Negro Magmatic Arc and the Costeiro and Cabo Frio domains (Fig. 1). The RNC (Rio Negro Complex, Tupinambá et al. 1996) comprises tonalitic to trondhjemitic orthogneisses, hornblende gabbro and quartz diorite stocks from subductionrelated magmatism (Tupinambá et al. 2000). Syn-collisional leucogranites with banded and homophonous textures crosscut the Rio Negro Complex orthogneisses (Tupinambá 1999). A megasheet of granodioritic to granitic orthogneiss (Serra dos Órgãos Batholith, Barbosa & Grossi Sad 1985) was emplaced during the syn- to late-collisional orogenic phase. Late to post-collisional non-foliated granite stocks and sills are also present (Junho 1993). The country rocks of the plutonites are high-grade metasediments of the Paraíba do Sul Group (Ebert 1968), comprising garnet-(cordierite)-(sillimanite)-biotite gneisses, quartzites, calcsilicate rocks and marbles. The Rio Negro Magmatic Arc occupies 2/3 of the area of the Oriental Terrane, almost 600-km along the Atlantic Coast, from northern São Paulo to southern Espirito Santo (Fig.1). The main deformation in the Oriental Terrane is characterized by: a) migmatitic and locally milonitic foliation within the metasedimentary rocks; b) folding of this foliation by kilometer-scale recumbent folds with NW dipping axial plane and N trending axis; b) coarse grained foliation and discrete shear zones within the orthogneisses, parallel to the recumbent folds axial plane. Late deformation is represented by two sets of normal open to tight folds with NE and NW trending axis. Discrete vertical dipping transpressional and transtensional shear zones are also related to the late stage deformation. The RNC orthogneisses were formely considered as a Paleoproterozoic basement (Machado & Demange 1994). Published Rb-Sr isochronic ages of granitoid gneisses from the Oriental Terrane similar to the RNC rocks are usually older than 600 Ma (Fonseca et al. 1984; Batista & Kawashita 1985; Tassinari 1988; Dias Neto et al. 1995; Machado 1997). A leucogranite gneiss closely related to the Rio Negro Complex yelded a 620 +/- 20 Ma concordant zircon age (Delhal et al. 1969; Tupinambá et al. 1997). In the northern Ribeira Belt, orthogneisses from the Rio Doce Magmatic arc (Figueiredo & Campos Neto 1993) yielded younger U-Pb zircon ages (590 to 570 Ma, Söllner at al 1991). LITOGEOCHEMICAL AND ISOTOPIC DATA The Rio Negro Complex (RNC) performs a magmatic series that enriches in Na2O and is depleted in CaO and K2O. It is very different from the Serra dos Órgãos Batholith (SOB) magmatic series that is a high-K20 series at its final members. The albite/anortite/orthoclase normative diagram (fig. 2d) illustrates the tonalite-throndhjemite RNC series1, while BSO series is a typical tonalite-granodiorite-granite series. The syn-collisional Leucogranite Gneisses do not constitute a magmatic series. They perform a cluster of points (as the SOB leucocratic facies) in the high-K field of the SiO2 x K20 diagram (fig. 2b). The post-collisional granitoids are products of a typical high-K20 calcalkaline magmatic series (fig. 2b). Tectonic diagrams also demonstrate differences between the magmatic phases. RNC samples align along a pre-collisional trend at R1XR2 diagram (fig. 3a). The SOB samples are divided into two groups at the same diagram: the first group align at the late-collisional trend (granodioritic facies) while the second group (mainly the leucocratic facies) plots together with the Leucogranite Gneisses at the syn-collisional field. Post-collisional granitoids plot (together with some SOB samples) at the post-orogenic field at a tectonic discrimination diagram (fig. 3b). 1

The complete magmatic series is a gabbro-diorite-tonalite-throndjhemite series.

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To illustrate the differences between the magmatic products, we also elaborate diagrams based on Arvin & Rostamizadeh (1997) criteria that clearly separates the plutonic phases (fig. 3c,d). At the Central Ribeira Belt, the geochronological data base (fig. 4) points to a series of well defined tectonic and magmatic events during the Brasiliano-Pan African orogen (Tupinambá et al. 2000): 1. a pre-collisional phase with ages older than 600 Ma – the Rio Negro Magmatic Arc. 2. a syn-collisional phase with widespread migmatization and leucogranite generation around 600 Ma. 3. a calc-alkaline cordilleran magmatism during 580 and 550 Ma – the Serra dos Órgãos Batholith. 4. a large post-collisional phase, between 540 and 480 Ma. The Sr evolution diagram (fig. 5) shows that pre and post-collisional rocks were not contaminated by Paleoproterozoic basement rocks. SOB samples were partially contaminated by a special type of Paleoproterozoic rock – the Quirino Unit. The Nd evolution diagram (fig. 6) also reveals the same juvenile characteristic of the magmatism. TECTONIC AND MAGMATIC EVOLUTION The existence of a huge magmatic at the Oriental Terrane of the Ribeira Belt brings new constraints on the palaeogeography of the orogenic zone. The geological cross section from the São Francisco Craton to the Serra do Mar at the Rio de Janeiro State presents a Brasiliano –PanAfrican collisional orogen (fig. 7): a) a passive continental margin (Andrelândia marginal Basin, Paciullo et al. 1988 and a gneissic Transamazonian (2.2-2.0 Ga) basement -- the attenuated crust of the São Francisco Craton; b) a tectonic domain where the metasedimentary coverture folds together with its basement (Andrelandia Domain, Heilbron et al 1995); c) a Craton-vergent imbricated tectonic domain where the the cover delaminates from its basement (Juiz de Fora Domain, Heilbron et al. 1995); d) a megasynformal structure containing a Klippe at its top (Paraiba do Sul Klippe, Heilbron et al. 2000); e) the Central Tectonic Boundary, a palaeosuture between the Sao Francisco Craton passive margin and another block, the Oriental Terrane; f) the Oriental Terrane: forearc metamorphosed sediments, the Rio Negro Magmatic Arc and syn, late and post-collisional granitoids; g) another palaeosuture between the Oriental Terrane and the Cabo Frio Terrane, related to a Lower Palaeozoic event – the Buzios Orogeny. The pre-collisional phase is marked by the magmatic accretion of the Rio Negro Arc. Its minimum age is 637 +/- 10 Ma, U/Pb zircon age of a tonalite gneiss (Tupinambá et al 1998b; Tupinambá 1999). The dip of the subducting slab was to east/southeast, due to the geographical position of the arc (fig. 8a). The absence of a continental basement at the Oriental Terrane, the isotopic and geochemical data suggest that the Rio Negro Arc was emplaced in a oceanic crust, or a very thin continental crust. Probably, the collision was due to the arrival of São Francisco Craton passive margin at the subduction zone. The arc/trench interval imediately decreased until the arc and its roots have docked at the passive margin (fig. 8b, 8c). The magmatic record of the collisional event is the widespread ocurrence of homogeneous, gneissic or diatexitic leucogranites (599 +/- 5 and 589 +/- 6 Ma, Pb/Pb zircon age, Tupinambá 1999). All of them present stable muscovite but do not show a clear S-

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granitoid characteristic. The leucogranites do not always have the same source – they could be associated to orthogneisses of the Rio Negro Complex or present gradational contacts to metasediments. Rather they are probably magmatic products of favorable thermodynamic conditions: the overpressure and the increase of heat flow due to crustal duplication during the collision (Bonin 1991). The crust was thicker near the suture – the Central Tectonic Boundary, producing a giant mass of leucogranites at the top of the Oriental Terrane. The Serra dos Órgãos Batholith have crystallized during the interval 580-546 Ma (580 +/- 17 Ma, leucocratic granitic facies Pb/Pb zircon age; 560 +/- 4 Ma, granodiorite facies U/Pb zircon age; 546 +/15 Ma, tonalite facies U/Pb zircon age – all from Tupinambá 1999). The ordering of ages and facies is somewhat paradoxal: the older the age more felsic and potassic was the magmatism. One hypothesis to explain the fact is the availability of granitic melts at the crust during the beginning of the SOB magmatism. These melts were probably mixed with the SOB primary magma to produce the granitic leucocratic facies. After the collision, the cooled country rocks do not allow contamination, letting the SOB crystallize more primitive magmas. The metaluminous calcic to calc-alkaline SOB magmatism was emplaced at the Oriental Terrane and could not be generated by the pre-600 Ma eastward-dipping subduction zone. One possible explanation is the reversal of the subduction dip zone, consuming an oceanic crust to the east of the stacked Oriental Terrane (fig. 8d). The final collapse of the orogen during its uplift and cooling produced a number of NW trending ductile-ruptile shear zones (fig. 8e). Along the zone many stocks and plutons of post-collisional granitoids were transported and emplaced (500 Ma +/- 20 Ma, Rb/Sr isochronic age, Tupinambá 1999).

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FIELDTRIP STOPS 2 First day A geological cross-section along the BR-040 (figure 10) STOP I-1 – Belvedere at BR-040. Landscape view of the Coastal Plain and Guanabara Bay (figure 11) UTM coordinates: 682042 E; 7505105 N.3 From the base to the top of the Serra do Mar range the road cuts rocks from the Rio Negro Complex (RNC, Tupinambá et al 1996). Brief comments about the geological and geomorphological evolution of the Serra dos Órgãos mountains. STOP I-2 – Bingen Quarry. Type-locality of the Bingen Unity – a syn-collisional leucogranite gneiss (figure12) UTM coordinates: 697824 E; 7520256 N. It is a porphyroblastic biotite gneiss with a tonalitic matrix and K-feldspar megacrysts with irregular borders corroded by quartz. Relict banded gneisses can be locally observed. The mafic bands are biotite rich mafic tonalites presenting clorite pseudomorphs (pyroxene ?) and titanite as the main accessory mineral. Different generations of leucogranitic and pegmatitic veins crosscut the tonalitic gneiss. The Bingen Unity is interpreted as a diatexite (Penha et al. 1979, 1980). Pb/Pb zircon ages of 599 +/- 5 and 589 +/- 6 Ma were obtained by Tupinambá (1999) for similar leucogranite gneisses. STOP I-3 – Southern contact of the Serra dos Órgãos Batholith at BR-040 near Araras (figure 13) UTM coordinates: 681744 E; 7509864 N. This outcrop was first described by Penha & Wiedemann (1984). At the road section one can observe a contact between the Rio Negro Complex (RNC) and the Serra dos Órgãos Batholith (SOB). The RNC gneiss presents a higher angle milonitic foliation (304/68) and the SOB a lower angle primary foliation (325/30). The contac is quite concordant, and some primary igneous irregularities can be found at the scale of the outcrop. The leucocratic facies yielded a Pb/Pb zircon age of 580 +/- 17 Ma. U/Pb zircon age of the granodioritic facies is 560 +/- 4 Ma and 546 +11/-15 Ma for a restricted tonalite facies (Tupinambá 1999). STOP I-4 -- Rio Negro Complex homogeneous tonalite gneiss at Araras quarry (figure 14) UTM coordinates: 684879 E; 7519290 N. It is a large exposition of tonalites and granodiorites of the Rio Negro Complex. Hornblende and titanite are visible at hand lens examination. Small aplitic veins also contain hornblende megacrystals. Gabbroic and dioritic restites are locally observed. U/Pb zircon age of a tonalite gneiss at Sumidouro, 50 km NE from Araras, yielded 634 +/- 10 Ma (Tupinambá et al 1998). 2 3

Stop locations in figure 9. UTM coordinates origin: Equator and 45o W meridian.

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STOP I-5 -- Northern contact of the Serra dos Órgãos Batholith at BR-040 near Araras (figure 15) UTM coordinates: 692480 E; 7531290 N. The road goes through the Serra dos Órgãos Batholith (SOB) and reaches the upper contact with Rio Negro Complex (RNC). The stop is a roadcut almost two quilometers long, near the road to Pedro do Rio. STOP I-6: Geological cross section on the Rio Negro Complex between Pedro do Rio and Areal (figure 16): There is a 12 km (map thickness) of Rio Negro Complex rocks between the Serra dos Órgãos Batholith upper contact and the Central Tectonic Boundary. The section begins with a predominance of a melanocratic quart dioritic poorly foliated rock. The augen gneiss lenses and bands occur only at the first kilometer near the SOB contact. At the middle of the section, the number of discordant and concordant leucogranitic dikes increase until it is found a 500 meter thick sheet of a leucogranite gneiss. To the end of the section there is a banded migmatitic gneiss completely surrounded by leucogranite gneiss. It is a fine banded sillimanite-biotite paragneiss that shows melanossome and leucossome bands. It contains also mafic quart dioritic bands, probably earlier dykes. The constrast between mafic quartz dioritic bands and leucogranite gneiss is clearly shown at a small quarry near Areal (figures 17 and 18). It is the locality where Delhal et al (1969) collected samples for the first U/Pb age determinations at the Ribeira Belt. At that time, these migmatites were called Serra dos Örgãos Series by Rosier (1957, 1965) who believes they were Archean rocks partially melted at the Neoproterozoic to generate orthogneisses and granites. The obtained U/Pb zircon age at the outcrop, 620 ± 20 Ma was interpreted by the authors (Delhal et al 1969; Cordani et al 1973) as the time of syntectonic magmatism at the Serra dos Órgãos region. Years later, Barbosa & Grossi Sad (1985) excluded the Serra dos Órgãos Batholith (mainly coarse grained granodiorite gneisses) from the Serra dos Órgãos Series. Tupinambá et al (1997) attempted to the fact that some authors were still considering the migmatites as pre-Brasiliano rocks and the age of 620 ± 20 Ma (Delhal et al 1969) as the age of crystallization of the Serra dos Órgãos Batholith. The section ends at the Central Tectonic Boundary. Its a tectonic contact between the Rio Negro Complex and high grade garnet biotite paragneisses, quartzites and calcissilicates. End of the first day

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Second day Returning to Rio de Janeiro along the BR-116 road The day begins with a beatiful trip along the “Caminho da Hortênsias”, the road between Petrópolis and Teresópolis. It crosscuts the Serra dos Órgãos Batholith and numerous stocks of post-collisional plutons that are the highest peaks of the region. STOP II-1: Highest portion of the RJ-15 Road. UTM coordinates: 700901 E; 752020N; 1,280 m height. Old landslide area. Outcrop of Teresópolis Granite, a post-collisional granite. It is a reddish gray granite, titanite and allanite bearing and presenting millimetric feldspar phenocrystals. It is related to an extensive post-collisional magmatism at the Central Ribeira Belt at 500 Ma (isochronic Rb/Sr age, Tupinambá 1999). These I-type granitoids are very homogeneous and show magmatic mixing structures (Junho 1993). STOP II-2: Aranda Store – orchids The Aranda Store presents one of the largest brazilian’s Atlantic Rain Forest orchids exposition. STOP II-3: Pimenteiras Quarry (figure 19) At the quarry one can observe contact relationships between the Rio Negro Complex (RNC) and the Serra dos Órgãos Batholith (SOB). The SOB presents its typical facies: a hololeucocratic granitic facies and a mesocratic granodioritic facies. The former is full of mafic dioritic enclaves, hornblende bearing felsic pods, and coarse grained lenses with garnet and biotite. The latter is in contact with a 10-20 meters thick lens of RNC dioritic to tonalitic gneiss. Garnet bearing reaction borders occur at the contact between diorites and leucossome pods of the SOB. STOP II-4: Pedreira da Posse (Posse Quarry) UTM coordinates: 706210 E; 7524901 N A 15 m thick lens of Serra dos Órgãos Batholith (SOB) is enclosed by Rio Negro Complex (RNC) gneisses at this quarry. The RNC gneisses present dioritic bands and a porphyroblastic facies. A gabbroic lens is also within the RNC gneisses. Subvertical dykes of a pink granite crosscuts the gneisses. STOP II-5: Suruí Quarry, Suruí Granite type-locality (figure 20) The Suruí Granite crops out in the Coastal Plain (Baixada Fluminense) and in some islands of the Guanabara Bay. It is a porphyritic late collisional plutonic rock with a strong primary foliation due to the alignment of the k-feldspar megacrystals 4. Its quartz dioritic matrix shows recrystallization textures. A thick (10 –15 m) dioritic dyke5 crosscuts the Suruí Granite at the quarry. It is a biotite bearing fine grained rock full of acessory minerals (apatite, opaque minerals and 4

The megacrystals of the Suruí Granite are mainly microcline. The matrix is constituted by xenoblastic quartz and small plagioclase crystals. The mineral assemblage titanite + ilmenite is a distinctive feature of the Suruí Granite and other late to post-collisional granites at the Ribeira Belt. The widespread occurence of sericite and clorite denotes low grade alteration of the granite. 5 Biotite bearing tonalite to diorite rock. The acessory minerals are apatite, opaque mineral, zircon, carbonate and chlorite. Near the wall rock, the brownish biotite changes to a dark green variety, the concentration of titanite increases and chlorite and carbonate are present as xenomorphic aggregates.

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zircon). Clorite and carbonate crystals are common. The primary igneous foliation of the dyke is not concordant with the Suruí granite foliation. At its margin, the dyke presents centimetric granophyric borders. Its quartz/feldspar intergrowths are parallel to the igneous foliation of the dike.

REFERENCES ALMEIDA, J. C. H.; TUPINAMBÁ, M., HEILBRON, M. & TROUW, R. - 1998 - Geometric and kinematic analysis at the Central Tectonic Boundary of the Ribeira Belt, Southeastern Brazil. In Congresso Brasileiro de Geologia, 39, Belo Horizonte, SBG. Anais..., pág. 32. BARBOSA,A.L.M. & GROSSI SAD,J.H. - 1985 - Batólito granítico da Serra dos Órgãos, Estado do Rio de Janeiro, Brasil. Contrib. Geol. Petrol. Núcleo de Minas Gerais, SBGM, 1985:49-61. BONIN, B.; LAMEYRE, J. & LeFORT,P. – 1991 – Role of tectonic overthrusting on the vertical mobility of crustal anatetic melts. J. Geoph. Res. ser. A, 1385: 211-225. CORDANI, U.G., DELHAL,J. & LEDENT,D. -1973 - Orogeneses superposées dans le précambrien du Brésil Sud-Oriental (Etats de Rio de Janeiro et Minas Gerais). Rev. Bras. Geoc., v. 3: 1-22. DELHAL, J.;LEDENT,D.;CORDANI,U.G. - 1969 - Ages U/Pb, Sr/Rb et Sud-Est du Brésil (États de rio de Janeiro et de Minas Gerais). Ann. Soc. Géol. Belg., 92: 271-283. HEILBRON, M.; MOHRIAK, W.; VALERIANO, C. M.; MILANI, E. J.; ALMEIDA, J. & TUPINAMBÁ, M. - 2000 - From collision to extension: the roots of the southeastern continental margin of Brazil. In Mohriak,W. Talwani, M. (ed.): Atlantic Rifts and Continental Margins. Geophysical Monograph 115, American Geophysical Union: 1-31.

HEILBRON,M.;VALERIANO,C.M.;VALLADARES,C.& MACHADO, N. - 1995 - A orogênese brasiliana no segmento central da Faixa Ribeira, Brasil. Rev. Bras.Geoc. 25 (4): 249 - 266. JUNHO, M.C.B. - 1993 - Granitóides Brasilianos da Região Central do Estado do Rio de Janeiro Geoquímica preliminar, An. Acad. Bras. Cienc., 65, II: 161-179. PACIULLO, F. V. P., RIBEIRO, A, ANDREIS, R. & TROUW, R. 1998. Sedimentary, Igneous and Thermo-tectonic Events in the Folded belts at the southern border of the São Francisco Craton. International Conference On Precambrian And Craton Tectonics / 14th International Conference On Basement Tectonics, Ouro Preto, Brazil 1998. Abstracts: 68-69. PENHA,H.M. & WIEDEMANN, C.M. – 1984 – Granitóides da região central do Estado do Rio de Janeiro. Excursão. In CONGR. BRAS. GEOL., 33, Rio de Janeiro, 1984, Anais...., Rio de Janeiro, SBG. V. 12, p. 5433-5455. PENHA, H. M.;FERRARI, A. L.; JUNHO, M.C.B.; SOUZA,S.L.A. & BRENNER,T.L. - 1981 Projeto Folha Itaipava, rel.fin., vol. I. Proj. carta geológica do Estado do RJ, DRM/IG-UFRJ, 177 pag., inédito. -----------------; FERRARI, A. L.;RIBEIRO, A.; AMADOR, E. S.; PENTAGNA, F. V.; JUNHO, M. C. B.; & BRENNER, T. L. - 1979 - Projeto Folha Petrópolis, rel.fin., vol. I. Proj. carta geológica do Estado do RJ, DRM/IG-UFRJ, 256 pag., inédito. -----------------; FERRARI, A. L. ;RIBEIRO, A. ;AMADOR, E. S.; PENTAGNA, F. V.; JUNHO, M. C. B.; & BRENNER, T. L. - 1980 - A geologia da Folha Petrópolis. In: Congresso Brasileiro de Geologia, 31, Balneário de Camboriú, 1980. Anais... Balneário de Camboriú, SBG. V.5, P.29652974. ROSIER,G.F. - 1957 - A geologia da Serra do Mar, entre os picos de Maria Comprida e do Desengano (Estado do Rio de Janeiro). Dep. Nac. Prod. Mineral, Div. Geol. Mineral., bol. 166. ----------------- - 1965 - Pesquisas geológicas na parte oriental do Estado do Rio de Janeiro e na parte vizinha de Minas Gerais. Bol.222. Div. Geol. Min. DNPM. Rio de Janeiro. TUPINAMBÁ,M. – 1999 – Evolução tectônica e magmática da Faixa Ribeira na região serrana do Estado do Rio de Janeiro. Phd Thesis, Universidade de São Paulo, Instituto de Geociências, 218 p. unpubl.

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10 TUPINAMBÁ, M.; HEILBRON, M.;OLIVEIRA, A.; PEREIRA, A. J.; CUNHA, E. R. S. P.; FERNANDES, G. A.; FERREIRA, F. N. ; CASTILHO, J. G.; TEIXEIRA, W. - 1996 - Complexo Rio Negro - uma unidade estratigráfica relevante no entendimento da evolução da Faixa Ribeira. 39o.Congr. Bras. Geol. in Anais. TUPINAMBÁ, M.; TEIXEIRA, W.; DUARTE, B.P. & HEILBRON,M. - 1997 - U.G. Cordani & J. Delhal’s geochronological data from the Ribeira Belt revisited after thirty years. In: SouthAmerican Symposium on Isotope Geology, Campos do Jordão, 1997. Ext. Abstr... p. 320-322. TUPINAMBÁ, M.; TEIXEIRA, W. & HEILBRON,M. – 2000 - Neoproterozoic Western Gondwana assembly and subduction-related plutonism: the role of the Rio Negro Complex in the Ribeira Belt. Rev. Bras. Geoc., 30 (1): 7-11. TUPINAMBÁ, M.; TEIXEIRA, W.; HEILBRON, M. & BASEI, M. - 1998 - U/Pb zircon age and litogeochemistry of the Rio Negro Complex tonalitic gneiss: evidence of a 630 Ma magmatic arc at the Costeiro Domain of the Ribeira Belt. In Congresso Brasileiro de Geologia, 39, Belo Horizonte, SBG. Anais..., pág. 51. TUPINAMBÁ,M.; TEIXEIRA, W.; HEILBRON, M. & BASEI, M. – 1998b - The Pan-African / Brasiliano arc-related magmatism at the Costeiro Domain ot the Ribeira Belt, southeastern Brazil. In International Conference on Basement Tectonics, 14, Ouro Preto pág 12-14. TUPINAMBÁ, M.; VALERIANO, C.M.; HEILBRON, M.; TEIXEIRA,W. – 2000 -- Magmatic record of subduction, continental collision and tectonic collapse during western Gondwana assembly at the Oriental Terrane of the Ribeira Belt (SE Brazil). In 31 International Geological Congress, Proceedings, CD-ROM. WIEDEMANN, C.M.; PENHA, H.M. & SCHMIDT-TOMÉ, R. – 1987 – Granitoids of Espírito Santo and Rio de Janeiro States (excursion guide). Rev. Bras. Geoc., 17(4): 674-689.

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