Dating high quality syn-orogenic plutons and you can supracrustal stones for the an attractive orogen – Ribeira strip case-investigation

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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 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 (D_1+dos) and was folded by the megascale F₃-folds ( Fig. 4E).

Regardless if one of these plutons mix-cut the CFTD within its NW idea, brand new Silva Jardim Pluton, old on 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 http://www.datingmentor.org/cs/iamnaughty-recenze 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 surrounding China Terrane ( Figs. 2 and 3), there are also metamorphic age ca. 550 – 510 Ma ( Schmitt ainsi que al. 2004 Schmitt Roentgen.S., Trouw R.A good.J., Van Schmus W.R., Pimentel Meters.Meters. 2004. Late amalgamation regarding the central part of Western Gondwana: the latest geochronological data and the characterization out of an excellent Cambrian collisional orogeny regarding Ribeira Belt (SE Brazil). Precambrian Look , -61. , 2012a Schmitt R.S., Mendes J.C., Peternel Roentgen., Silva L.C., Dantas E.L. 2012a. : SSAGI, Medellin, Colombia. ; Fernandes et al. 2015 Fernandes Grams.L., Schmitt R.S., Bongiolo E., Mendes J.C., Basei Yards. 2015. Unraveling the fresh new tectonic advancement away from good Neoproterozoic-Cambrian energetic margin on the Ribeira Orogen (SE Brazil): U-Pb and you can Lu-Hf provenance research. Precambrian Search , -360. ). Additionally, several plutons which have years from 510 to help you 480 Ma intrude so it terrane and tend to be interpreted while the article-tectonic ( Valeriano ainsi que al. 2011 Valeriano C.Yards., Tupinamba M., Simonetti An excellent., Heilbron M., Almeida J.C.H., Eirado L.G. 2011. U-Pb Los angeles-MC-ICPMS geochronology from Cambro-Ordovician blog post-collisional granites of Ribeira buckle, the southern area of Brazil: terminal Brasiliano magmatism inside central Gondwana supercontinent. Log out of Southern Western World Sciences , -428. ). 2 and 3) ( Moraes 2009 Moraes J.Yards. 2009. Geologia manage Granito Silva Jardim (RJ): Implicacoes na evolucao tectonica 2 Terrenos Oriental age Cabo Frio. Master Thesis UERJ. 65 p. ). So it pluton gift ideas an established igneous foliation which is thought a beneficial late-collisional magmatic human body ( Moraes 2009 Moraes J.Meters. 2009. Geologia would Granito Silva Jardim (RJ): Implicacoes na evolucao tectonica dos Terrenos China e Cabo Frio. Learn Thesis UERJ. 65 p. ). The newest youngest magmatic intrusions entered on the CFTD when you look at the Paleozoic try article tectonic pegmatites and you can granites out-of california. 440 Ma old having You-Pb into the zircon ( Schmitt ainsi que al. 2004 Schmitt R.S., Trouw Roentgen.An effective.J., Van Schmus W.Roentgen., Pimentel Yards.Meters. 2004. Late amalgamation from the central section of Western Gondwana: the latest geochronological study while the characterization from a great Cambrian collisional orogeny regarding Ribeira Buckle (SE Brazil). Precambrian Lookup , -61. , Bongiolo et al. 2015 Bongiolo Elizabeth., Renac C., D’Almeida de Toledo P., Schmitt Roentgen.S., Faulstich F.Roentgen.L., Mexias , Silva F.P.C. 2015. Source regarding pegmatites and you may liquids at the Ponta Negra (RJ, Brazil) while in the later- to publish-collisional level of your Gondwana Construction. Lithos , -275. ).