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The deformation and high grade metamorphism responsible for the tectonic inversion of the sedimentary basin is attributed to an orogenic event of Cambrian age. Schmitt et al. (200cuatro Schmitt R.S., Trouw R.A.J., Van Schmus W.R., Pimentel M.M. 2004. Late amalgamation in the central part of West Gondwana: new geochronological data and the characterization of a Cambrian collisional orogeny in the Ribeira Belt (SE Brazil). Precambrian Research , -61. , 2008b Schmitt R.S., Trouw R.A.J., Van Schmus W.R., Passchier C.W. 2008b. Cambrian orogeny in the Ribeira Belt (SE Brazil) and correlations within West Gondwana: ties that bind underwater. : Pankhurst R.J., Trouw R.A.J., Brioto Neves B.B., De Wit M.J. (eds.) West Gondwana: Pre-Cenozoic Correlations across the South Atlantic Region . Geological Society, London , Special Publications, -296. ) dated the D1+2 syntectonic leucosome from both basement and supracrustals, and defined a ca. 5step three0 Ma tectonometamorphic event related to a convergent margin that culminated with a continental collision (Buzios Orogeny). This partial melt product was generated during the metamorphic peak (D1+2) and was folded by the megascale F3-folds ( Fig. 4E).
No matter if one among them plutons get across-slice the CFTD within the NW tip, the latest Silva Jardim Pluton, old within 505 Ma ( Figs
In the basement, the lower intercepts of the U-Pb discordia lines are in the interval between 600 and 450 Ma, consistent with this event ( Schmitt et al. 2004 Schmitt R.S., Trouw R.A.J., Van Schmus W.R., Pimentel M.M. 2004. Late amalgamation in the central part of West Gondwana: new geochronological data and the characterization of a Cambrian collisional orogeny in the Ribeira Belt (SE Brazil). Precambrian Research , -61. , 2008b Schmitt R.S., Trouw R.A.J., Van Schmus W.R., Passchier C.W. 2008b. Cambrian orogeny in the Ribeira Belt (SE Brazil) and correlations within West Gondwana: ties that bind underwater. : Pankhurst R.J., Trouw R.A.J., Brioto Neves B.B., De Wit M.J. (eds.) West Gondwana: Pre-Cenozoic Correlations across the South Atlantic Region . Geological Society, London , Special Publications, -296. ). The metamorphic rims of the Paleoproterozoic zircon grains in the shear zones are dated at ca. 505 Ma ( Schmitt et al. 2008b Schmitt R.S., Trouw R.A.J., Van Schmus W.R., Passchier C.W. 2008b. Cambrian orogeny in the Ribeira Belt (SE Brazil) and correlations within West Gondwana: ties that bind underwater. : Pankhurst R.J., Trouw R.A.J., Brioto Neves B.B., De Wit M.J. (eds.) West Gondwana: Pre-Cenozoic Correlations across the South Atlantic Region . Geological Society, London , Special Publications, -296. ). In the supracrustals, all metamorphic minerals are formed during the Cambrian (ca. 530 Ma). Zircon, monazite, sphene and rutile were dated and yielded a metamorphic time interval between 525 and 510 Ma for the eastern CFTD and 505 – 490 Ma for the western CFTD ( Schmitt et al. 2004 Schmitt R.S., Trouw R.A.J., Van Schmus W.R., Pimentel M.M. 2004. Late amalgamation in the central part of West Gondwana: new geochronological data and the characterization of a Cambrian collisional orogeny in the Ribeira Belt (SE Brazil). Precambrian Research , -61. ). The occurrence of a late F4-reclined megascale fold in the western region could partially explain this ( Fig. 3). These younger ages could indicate that units in this region stayed deeper in the crust and the D4 deformational phase would bring them up later. The cooling rate calculated for the eastern part of CFTD is rapid until ca. 510 Ma (more than 20 o C/Ma), and after this diminishes to 5 – 10 o C/Ma ( Schmitt et al., 2004 Schmitt R.S., Trouw R.A.J., Van Schmus W.R., Pimentel M.M. 2004. Late amalgamation in the central part of West Gondwana: new geochronological data and the characterization of a Cambrian collisional orogeny in the Ribeira Belt (SE Brazil). Precambrian Research , -61. ).
In the surrounding Oriental Terrane ( Figs. 2 and you will 3), there are also metamorphic ages of california. 550 – 510 Ma ( Schmitt et al. 2004 Schmitt Roentgen.S., Trouw R.A beneficial.J., Van Schmus W.R., Pimentel Meters.M. 2004. Late amalgamation on main part of West Gondwana: the latest geochronological studies together with characterization off an effective Cambrian collisional orogeny in the Ribeira Gear (SE Brazil). Precambrian Search , -61. , 2012a Schmitt Roentgen.S., Mendes J.C., Peternel Roentgen., Silva L.C., Dantas Elizabeth.L. 2012a. : SSAGI, Medellin, Colombia. ; Fernandes et al. 2015 Fernandes Grams.L., Schmitt Roentgen.S., Bongiolo E., Mendes J.C., Basei M. 2015. Unraveling this new tectonic advancement away from good Neoproterozoic-Cambrian www.datingmentor.org/cs/secret-benefits-recenze/ effective margin on the Ribeira Orogen (SE Brazil): U-Pb and Lu-Hf provenance studies. Precambrian Lookup , -360. ). Also, some plutons which have decades from 510 to 480 Ma intrude which terrane and are generally interpreted due to the fact blog post-tectonic ( Valeriano mais aussi al. 2011 Valeriano C.Meters., Tupinamba M., Simonetti An effective., Heilbron Meters., Almeida J.C.H., Eirado L.Grams. 2011. U-Pb Los angeles-MC-ICPMS geochronology away from Cambro-Ordovician post-collisional granites of the Ribeira buckle, the southern part of Brazil: critical Brasiliano magmatism in the central Gondwana supercontinent. Record of Southern Western Planet Sciences , -428. ). 2 and you can step 3) ( Moraes 2009 Moraes J.Yards. 2009. Geologia manage Granito Silva Jardim (RJ): Implicacoes na evolucao tectonica dos Terrenos China elizabeth Cabo Frio. Grasp Thesis UERJ. 65 p. ). This pluton gift ideas a centered igneous foliation which is experienced a beneficial late-collisional magmatic human body ( Moraes 2009 Moraes J.M. 2009. Geologia manage Granito Silva Jardim (RJ): Implicacoes na evolucao tectonica 2 Terrenos Chinese language e Cabo Frio. Grasp Thesis UERJ. 65 p. ). This new youngest magmatic intrusions registered on CFTD when you look at the Paleozoic try article tectonic pegmatites and you may granites off california. 440 Ma dated that have U-Pb from inside the zircon ( Schmitt mais aussi al. 2004 Schmitt Roentgen.S., Trouw Roentgen.A great.J., Van Schmus W.R., Pimentel Meters.M. 2004. Later amalgamation in the main part of Western Gondwana: new geochronological research and the characterization away from an effective Cambrian collisional orogeny about Ribeira Belt (SE Brazil). Precambrian Lookup , -61. , Bongiolo mais aussi al. 2015 Bongiolo Elizabeth., Renac C., D’Almeida de- Toledo P., Schmitt Roentgen.S., Faulstich F.Roentgen.L., Mexias , Silva F.P.C. 2015. Resource away from pegmatites and you may drinks within Ponta Negra (RJ, Brazil) through the late- to share-collisional degree of the Gondwana System. Lithos , -275. ).
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