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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. (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. ) dated the D1+2 syntectonic leucosome from both basement and supracrustals, and defined a ca. 5step 30 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).
Whether or not one among them plutons cross-cut the CFTD in its NW tip, the new Silva Jardim Pluton, dated 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. ).
Throughout the adjoining China Terrane ( Figs. dos and you can 3), there are even metamorphic period of california. 550 – 510 Ma ( Schmitt mais aussi al. 2004 Schmitt R.S., Trouw Roentgen.An excellent.J., Van Schmus https://datingmentor.org/interracial-chat-rooms/ W.Roentgen., Pimentel Yards.Meters. 2004. Later amalgamation throughout the main part of Western Gondwana: the fresh new geochronological study in addition to characterization of a good Cambrian collisional orogeny throughout the Ribeira Gear (SE Brazil). Precambrian Research , -61. , 2012a Schmitt Roentgen.S., Mendes J.C., Peternel Roentgen., Silva L.C., Dantas E.L. 2012a. : SSAGI, Medellin, Colombia. ; Fernandes et al. 2015 Fernandes G.L., Schmitt R.S., Bongiolo E., Mendes J.C., Basei M. 2015. Unraveling the tectonic development from a Neoproterozoic-Cambrian effective margin from the Ribeira Orogen (SE Brazil): U-Pb and you can Lu-Hf provenance data. Precambrian Lookup , -360. ). In addition, several plutons which have years away from 510 to help you 480 Ma intrude it terrane and therefore are interpreted since the article-tectonic ( Valeriano et al. 2011 Valeriano C.Yards., Tupinamba Meters., Simonetti A good., Heilbron Yards., Almeida J.C.H., Eirado L.Grams. 2011. U-Pb La-MC-ICPMS geochronology of Cambro-Ordovician post-collisional granites of one’s Ribeira belt, southeast Brazil: critical Brasiliano magmatism into the main Gondwana supercontinent. Diary off Southern area American Earth Sciences , -428. ). dos and step 3) ( Moraes 2009 Moraes J.Meters. 2009. Geologia would Granito Silva Jardim (RJ): Implicacoes na evolucao tectonica dos Terrenos Oriental elizabeth Cabo Frio. Grasp Thesis UERJ. 65 p. ). That it pluton gifts a formulated igneous foliation that will be noticed an excellent late-collisional magmatic body ( Moraes 2009 Moraes J.M. 2009. Geologia do Granito Silva Jardim (RJ): Implicacoes na evolucao tectonica 2 Terrenos Chinese language age Cabo Frio. Grasp Thesis UERJ. 65 p. ). The youngest magmatic intrusions registered throughout the CFTD within the Paleozoic are article tectonic pegmatites and you may granites out of ca. 440 Ma dated which have U-Pb in the zircon ( Schmitt et al. 2004 Schmitt Roentgen.S., Trouw Roentgen.A good.J., Van Schmus W.Roentgen., Pimentel Meters.Yards. 2004. Late amalgamation about central part of Western Gondwana: the geochronological study additionally the characterization out-of a Cambrian collisional orogeny in the Ribeira Gear (SE Brazil). Precambrian Lookup , -61. , Bongiolo ainsi que al. 2015 Bongiolo E., Renac C., D’Almeida de- Toledo P., Schmitt R.S., Faulstich F.Roentgen.L., Mexias , Silva F.P.C. 2015. Origin away from pegmatites and you can fluids during the Ponta Negra (RJ, Brazil) throughout late- to share-collisional level of your Gondwana System. Lithos , -275. ).
