Figure 1:
Location of the Paraná Basin in South America (A), simplified map with general geological and geomorphological features in São Paulo State (B) and the sampling site location within SGCP (C). Modified: Zálan et al. (1990Zalán P.V., Wolff S., Astolfi M.A.M., Vieira I.S., Conceição J.C.J., Appi V.T., Neto E.V.S., Cerqueira J.R., Marques A. 1990. The Paraná Basin, Brazil. In: Leighton M.W., Kolata D.R., Oltz D.F., Eidel J.J. Interior cratonic hasins. Tulsa, American Association of Petroleum Geologists Memoir, 51, p. 681-708.), Penteado (1976Penteado M.M. 1976. Geomorfologia do Setor Centro-Ocidental da Depressão Periférica Paulista. PhD Thesis, Universidade de São Paulo, 86 p.) and Costa (2006Costa M.N.S. 2006. Diagênese e alteração hidrotermal em rochas sedimentares da Formação Corumbataí, Permiano Superior, Mina Granusso, Cordeirópolis/SP. PhD Thesis, Universidade Estadual Paulista, Rio Claro, São Paulo, 140 p.).
Figure 2:
Schematic representation of the Corumbataí Formation in the SGCP region, with studied mines and its stratigraphic position. Modified: Zanardo et al. (2016Zanardo A., Montibeller C.C., Navarro G.R.B., Moreno M.M.T., Da Rocha R.R., Del Roveri C., Azzi A.A. 2016. Formação Corumbataí na região de Rio Claro/SP: petrografia e implicações genéticas. Universidade Estadual Paulista, São Paulo, Geociências, 35:322-345.). Mine 1 (P1.1, P1.2, P1.3); Mine 2 (P2.1, P2.2); Mine 3 (P3.1, P3.2, P3.3); Mine 4 (P4.1, P4.2, P4.3); Mine 5 (P5.1, P5.2, P5.3, P5.4); Mine 6 (P6.1, P6.2, P6.3, P6.4); Mine 7 (P7.1, P7.2, P7.3); Mine 8 (P8.1); Mine 9 (P9.1, P9.2, P9.3, P9.4) and Mine 10 (P10.1, P10.2, P10.3).
Figure 3:
Diffractograms for each mine profile. Where: T, total sample; Ill, illite; Kln, kaolinite; Sm, smectite; Chl, chlorite; Qtz, quartz; Mc, microcline; Ab, albite; Cal, calcite; Hm, hematite.
Figure 4:
Ternary diagram of the (Al2O3)/(CaO+Na2O)/(K2O) oxides, in molecular proportions, for the sedimentary samples (Nesbitt and Young, 1982Nesbitt H.W., & Young G.M. 1982. Early Proterozoic climates and plate motions inferred from major element chemistry of lutites. Nature, 299:715-717., 1984Nesbitt H.W., & Young G.M. 1984. Prediction of some weathering trends of plutonic and volcanic rocks based on thermodynamic and kinetic considerations. Geochimica et Cosmochimica Acta, 48(7):1523-1534. and 1989), in comparison to the Upper Crust (UC, data from Taylor and McLennan, 1985Taylor S.R., & McLennan S.H. 1985. The Continental Crust: Its Composition and Evolution. Blackwell. Oxford, 312 p.), Average Post-Archaean Australian Shale (PAAS, data from Taylor and McLennan, 1985Taylor S.R., & McLennan S.H. 1985. The Continental Crust: Its Composition and Evolution. Blackwell. Oxford, 312 p.) and Average North American Shale Composite (N ASC, data from Gromet et al., 1984Gromet L.P., Dymek R.F., Haskin L.A., Korotev R.L. 1984. The “North American shale composite”: Its compilation, major and trace element characteristics. Geochimica et Cosmochimica Acta, 48:2469-2482. and Taylor and McLennan, 1985Taylor S.R., & McLennan S.H. 1985. The Continental Crust: Its Composition and Evolution. Blackwell. Oxford, 312 p.).
Figure 5:
Chemical Index of Weathering, CIW = [(Al2O3)/(Al2O3+CaO+Na2O)] * 100 and Chemical Index of Alteration, CIA = [(Al2O3)/(Al2O3+ CaO + Na2O + K2O)] * 100 for the studied samples. Harnois (1988Harnois L. 1988. The CIW index: A new chemical index of weathering. Sedimentary Geology, 55(3-4):322.) and Nesbitt and Young (1982Nesbitt H.W., & Young G.M. 1982. Early Proterozoic climates and plate motions inferred from major element chemistry of lutites. Nature, 299:715-717.).
Figure 6:
Trace elements distribution for each mine profile. Data normalized by the Average North American Shale Composite (NASC; from Gromet et al., 1984Gromet L.P., Dymek R.F., Haskin L.A., Korotev R.L. 1984. The “North American shale composite”: Its compilation, major and trace element characteristics. Geochimica et Cosmochimica Acta, 48:2469-2482. and Taylor and McLennan, 1985Taylor S.R., & McLennan S.H. 1985. The Continental Crust: Its Composition and Evolution. Blackwell. Oxford, 312 p.).
Figure 7:
REE patterns for each mine profile. Data normalized by the C1 Chondrite (Evensen et al., 1978Evensen N.M., Hamilton P.J., O’nions R.K. 1978. Rare-earth abundances in chondritic meteorites. Geochimica et Cosmochimica Acta, 42(8):1199-1212.).
Figure 8:
ΣREE vs. samples. The diagram shows the concentration increase in the upper portion of each profile, with the exception of Mines 3, 6 and 10 where no significant changes in REE composition occurs.
Figure 9:
(A) Classification of terrigenous sandstones and shales using log(Fe2O3/K2O) vs. log (SiO2/Al2O3) (Herron, 1988Herron M.M. 1988. Geochemical classification of terrigenous sands and shales from core or log data. Journal of Sedimentary Research, 58(5):820-829.). (B) Discriminant function diagram for the provenance signatures of sandstone/mudstone suites using major elements (Roser and Korsch, 1988Roser B.P., & Korsch R.J. 1988. Provenance signatures of sandstone-mudstone suites determined using discriminant function analysis of major element data. Chemical Geology, 67(1-2):119-139.). In both diagrams only the less weathered samples from the bottom portion of the profiles was used.
Figure 10:
Incompatible elements plot for the studied samples. Th versus Sc, where Th/Sc = 1 ratio is that of the Upper Crust. La versus Th, where La/Th = 2.8 ratio is that of Upper Crust (data from Taylor and McLennan, 1985Taylor S.R., & McLennan S.H. 1985. The Continental Crust: Its Composition and Evolution. Blackwell. Oxford, 312 p.).
Figure 11:
Ternary plot of La-Th-Sc for the Corumbataí Formation samples after Cullers (1994Cullers R.L. 1994b. The chemical signature of source rocks in size fractions of Holocene stream sediment derived from metamorphic rocks in the Wet Mountains region, Colorado, USA. Chemical Geology, 113(3-4):327-343.). The Upper Crust (UC; Taylor and McLennan, 1985Taylor S.R., & McLennan S.H. 1985. The Continental Crust: Its Composition and Evolution. Blackwell. Oxford, 312 p.), Average Post-Archean Australian Shale (PAAS; Taylor and McLennan, 1985Taylor S.R., & McLennan S.H. 1985. The Continental Crust: Its Composition and Evolution. Blackwell. Oxford, 312 p.) and Average North American Shale Composite (NASC; Gromet et al., 1984Gromet L.P., Dymek R.F., Haskin L.A., Korotev R.L. 1984. The “North American shale composite”: Its compilation, major and trace element characteristics. Geochimica et Cosmochimica Acta, 48:2469-2482. and Taylor and McLennan, 1985Taylor S.R., & McLennan S.H. 1985. The Continental Crust: Its Composition and Evolution. Blackwell. Oxford, 312 p.) are plotted for comparisons.
Table 1:
Chemical composition of major elements as wt% and trace elements in ppm. Total Fe as Fe2O3, major and minor elements in % and trace elements in ppm, UC (data from Taylor & McLennan 1985Taylor S.R., & McLennan S.H. 1985. The Continental Crust: Its Composition and Evolution. Blackwell. Oxford, 312 p.), PAAS (data from Taylor & McLennan 1985Taylor S.R., & McLennan S.H. 1985. The Continental Crust: Its Composition and Evolution. Blackwell. Oxford, 312 p.) and NASC (data from Gromet et al. 1984Gromet L.P., Dymek R.F., Haskin L.A., Korotev R.L. 1984. The “North American shale composite”: Its compilation, major and trace element characteristics. Geochimica et Cosmochimica Acta, 48:2469-2482. and Taylor & McLennan 1985Taylor S.R., & McLennan S.H. 1985. The Continental Crust: Its Composition and Evolution. Blackwell. Oxford, 312 p.).
Table 2:
Chemical indexes calculated for the samples. CIA = [Al2O3 / (Al2O3 + CaO + Na2O + K2O)] × 100 and CIW = [Al2O3 / (Al2O3 + CaO + Na2O)] × 100 in molecular proportions. Eu/Eu* = Eucn/[(Smcn)(Gdcn) and cn: chondrite normalized.