Figure 1:
Simplified geologic map of the São Francisco craton and adjacent Brasiliano belts: Rio Preto (RB), Riacho do Pontal (RPB), Sergipano (SB), Araçuaí (ArB), and Brasília (BB). The inset indicates the location of the map in the tectonic scenario of West Gondwana (modified from Danderfer et al., 2015Danderfer A., Lana C.C., Nalini H.A., Costa A.F.O. 2015. Constraints on the Statherian evolution of the intraplate rifting in a Paleo-Mesoproterozoic paleocontinent: New stratigraphic and geochronology record from the eastern São Francisco craton. Gondwana Research, 28:668-688.). Chapada Diamantina (CD), Northern Espinhaço (NE), Central Espinhaço (CE) and Southern Espinhaço (SE).
Figure 2:
Stratigraphic columns produced by previous studies in different regions. Ages: 1Martins et al. (2008Martins M., Karfunkel J., Noce C. M., Babinski M., Pedrosa-Soares A.C., Cial A.N., Liu D. 2008. A sequência pré-glacial do Grupo Macaúbas na área-tipo e o registro da abertura do rifte Araçuaí. Revista Brasileira de Geociências, 38(4):761-772.), 2Danderfer et al. (2009Danderfer A., Waele B.D., Pedreira A.J., Nalini H.A. 2009. New geochronological constraints on the geological evolution of Espinhaço basin within the São Francisco Craton - Brazil. Precambrian Research, 170:116-128), 3Queiroga (2010Queiroga G. N. 2010. Caracterização de restos de litosfera oceânica do Orógeno Araçuaí entre os paralelos 17° e 21°S. PhD Thesis, Universidade Federal de Minas Gerais, Belo Horizonte.), 4Babinski et al. (2012Babinski M., Pedrosa-Soares A.C., Trindade R.I.F., Martins M., Noce C.M., Liu D. 2012. Neoproterozoic glacial deposits from the Araçuaí orogen, Brazil: Age, provenance and correlations with the São Francisco Craton and West Congo belt. Gondwana Research, 21:451-465.), 5Costa et al. (2014Costa A.F.O., Danderfer A., Lana C. 2014. O registro do vulcanismo calimiano no Espinhaço Central (MG): caracterização petrofaciológica, geoquímica e geocronológica. Revista Geociências, 33:119-135), 6Sousa et al. (2014Sousa F. R., Santos E.L., Jesus M.T., Medeiros V.C. 2014. Carta Geológica da Folha Mansidão, escala 1:1.000.000. Teresina, Serviço Geológico do Brasil, Programa Geologia do Brasil.), 7Castro (2014Castro M.P. 2014. Caracterização Geológica da Formação Capelinha como uma unidade basal do Grupo Macaúbas em sua área tipo, Minas Gerais. MS Dissertation, Departamento de Geologia, Universidade Federal de Ouro Preto, Ouro Preto, 113p.), 8Danderfer et al. (2015Danderfer A., Lana C.C., Nalini H.A., Costa A.F.O. 2015. Constraints on the Statherian evolution of the intraplate rifting in a Paleo-Mesoproterozoic paleocontinent: New stratigraphic and geochronology record from the eastern São Francisco craton. Gondwana Research, 28:668-688.), 9Kuchenbecker et al. (2015Kuchenbecker M., Pedrosa-Soares A.C., Babinski M., Fanning M. 2015. Detrital zircon age patterns and provenance assessment for pre-glacial to post-glacial successions of the Neoproterozoic Macaúbas Group, Araçuaiorogen, Brazil. PrecambrianResearch, 266:12-26.).
Figure 3:
(A) Geological map of the study area with locations of the measured sections 1-8 and the samples analyzed for U-Pb geochronology; (B) Geological cross section across the study area (A-A’) in a SW-NE direction.
Figure 4:
(A) General stratigraphic columns showing thickness for stratigraphic units (location shown in
Fig. 3); (B) Generalized stratigraphic column of the Santo Onofre Group (facies distribution schematic).
Figure 5:
Lithofacies from the Canatiba Formation (A) Massive mudstone (Fm lithofacies); (B) Laminated sandstone and mudstone (SF lithofacies); (C) Turbiditic deposits with a thickening-upward facies succession; (D and E) Photomicrograph of the sandy and mudy portion (respectively) of rhythmite (lithofacies SF) with elongate quartz grains (Qz), opaque mineral (Opq) and chloritoid (Cld).
Figure 6:
Lithofacies from the Rio Peixe Bravo Formation. (A) Medium to thick-bedded turbidite sandstones/pebbly sandstones with interbedded conglomerate and mudstone (Gmm and Fm lithofacies); (B) Lenticular conglomerate with sandstone clast (as marked) in massive sandstone showing erosional base(dashed line); (C) Massives sandstone and mudstone (Sm and Fm lithofacies) and polymict conglomerate (Gmm lithofacies); the arrows indicate to mudstone pebbles; (D) Medium-grained turbidites interbedded with mudstone lenses. (E) Photomicrograph of the Gmm lithofacies showing lithic fragment of quartzite (Lq) and mudstone (Lm).
Figure 7:
Lithofacies from the Barrinha Member. (A) Polymict clast-supported conglomerate (Gcm lithofacies). (B and C) Matrix-supported conglomerate (Gmm lithofacies); (D) Conglomerate with mudstone clast (Gmm lithofacies).
Figure 8:
Sample A1 (Canatiba Formation) (A) CL images of selected detrital zircon grains representative of the calculated age. The red circles show the spot analysis. (B) Relative probability diagram for the detrital zircons.
Figure 9:
Sample A2 (Rio Peixe Bravo Formation) (A) CL images of selected detrital zircon grains representative of the calculated age. The red circles show the spot analysis. (B) Relative probability diagram for the detrital zircons.
Figure 10:
Sketch’s showing the sedimentation and basin-fill history of the Santo Onofre basin, during (A) the open, deep-water lacustrine and/or marine phase and (B) the shallow to deep-water phase. In (C), a section showing the structural geometry from the inversion tectonics (constructed based on rules of structural balancing, respecting as much as possible the geological map and the integration of field data).
Figure 11:
(A) Analytical signal map. (B) Simplified geologic map of the central Espinhaço region. Modified from Souza et al. (2003Souza J.D., Kosin M., Heineck C.A., Lacerda Filho J.V., Teixeira L.R., Valente C.R., Bento R.V., Borges V.P., Santos R.A., Guimarães J.T., Leite C.A.S., Neves J.P., Carvalho L.M., Oliveira I.W.B., Pereira L.H.M. 2003. Folha SD. 23-Brasília. In: Schobbenhaus, C., Gonçalves, J.H., Santos, J.O.S., Abram, M.B., Leão Neto, R., Matos, G.M.M., Vidotti, R.M. (Eds.). Carta Geológica do Brasil ao Milionésimo, Programa de Levantamentos Geológicos Básicos do Brasil, CPRM, Brasília (Sistema de Informações Geográficas. Programa Geologia do Brasil). CD-ROM.), Pinheiro et al. (2014Pinheiro M.A.P., Lombello J.C., Queiroz S.F., Cuzzati T., Pinho J.M.M. 2014. Folha SD.23-Z-D-II-4 Santo Antônio do Retiro,, escala 1:50.000. Belo Horizonte, Serviço Geológico do Brasil, Projeto Geologia do Brasil.), Lombello et al. (2014Lombello J.C., Pinheiro M.A.P., Queiroz S.F., Rojas J.N., Pinho J.M.M. 2014. Folha SD.23-Z-D-V-4 Nova Aurora, escala 1:50.000. Belo Horizonte, Serviço Geológico do Brasil, CPRM, Projeto Geologia do Brasil), Queiroz et al. (2014Queiroz S.F, Pinheiro M.A.P., Lombello J.C., Rojas J.N., Pinho J.M.M. 2014. Folha SD.23-Z-D-V-2Rio Pardo de Minas, escala 1:50.000. Belo Horizonte, Serviço Geológico do Brasil, Projeto Geologia do Brasil.).
Figure 12:
Stratigraphic framework for the Macaúbas Supergroup.
Figure 13:
Cartoons to explain intracontinental rifting during the break-up of Rodinia, by Li et al. (2008Li Z.X., Bogdanova S.V., Collins A.S., Davidson A., De Waele B., Ernst R.E., Fitzsimons I.C.W., Fuck R.A., Gladkochub D.P., Jacobs J., Karlstrom K.E., Lul S., Natapovm L.M., Pease V., Pisarevsky S.A., Thrane K., Vernikovsky V., 2008. Assembly, configuration, and break-up history of Rodinia: a synthesis. Precambrian Research, 160:179-210.). (A) Initial fragmentation related to Santo Onofre rift. (B) Final major break-up event related to Macaúbas rift.