Figure 1:
A lithostratigraphic map and a geologic section (A-B) of the Bauru Basin. The red square, cycle and triangle are the positions of the outcrops in the study area.
Figure 2:
A chronostratigraphic chart of the eastern portion of the Bauru Basin, based on Amaral et al. 1967Amaral G., Bushee J., Cordani U.G., Kawashiita K., Reynolds J.H. 1967. Potassium-argon ages of alkaline rocks from Southern Brazil. Geochimica et Cosmochimica Acta, 31:117-142. (CSN sample); Hasui & Cordani 1968Hasui Y., & Cordani U.G. 1968. Idades potássio-argônio de rochas eruptivas mesozóicas do este mineiro e sul de Goiás. In: Brazilian Geology Congress Bulletin. Belo Horizonte, SBG, p. 139-143. (samples AX, C-3, S-10, S-31, A-C2-4, OB-SN, SB, S-1, P, T-2, B-1); Sonoki & Garda 1988Sonoki I.K., & Garda G.M. 1988. Idades K-Ar de rochas alcalinas do Brasil Meridional e Paraguai Oriental: compilações e adaptação às novas constantes de decaimento. Geoscience Institute Bulletin, 19:63-85. (samples CT, CS, CCI); Machado Junior 1992Machado Junior D.L. 1992. Idades Rb/Sr do complexo alcalino-carbonatítico de Catalão II (GO). In: 29th Brazilian Geology Congress Bulletin. São Paulo, SBG, p. 91-93. (sample CCII); Guimarães et al. 2012Guimarães G.B., Liccardo A., Godoy L.C., Weinshutz L.C., Manzig P.C., Vega C.S., Pilatti F. 2012. Ocorrência de Pterossauros no Cretáceo da Bacia do Paraná/Bauru: implicações para a geoconservação, paleontologia e estratigrafia. In: 46th Geology Brazilian Congress. Santos, SBG. and Fragoso et al. 2013Fragoso C.E., Weinschutz L.C., Vega C.S., Guimarães G.B., Manzig P.C., Kellner A.W. 2013. Short note on the pterosaurs from the Caiuá Group (Upper Cretaceous, Bauru Basin), Paraná State, Brazil. In: International Symposium on Pterosaurs, Rio de Janeiro. Short Communications, p. 71-72. (Pterosaurs); Gobbo-Rodrigues 2001Gobbo-Rodrigues R.S. 2001. Carófitas e Ostracódes do Grupo Bauru. MS Dissertation, Instituto de Geociências e Ciências Exatas, Universidade Estadual Paulista “Júlio de Mesquita Filho”, Rio Claro, 137p. and Dias-Brito et al. 2001Dias-Brito D., Musacchio E.A., Castro J.C., Maranhão M.S.A.S., Suarez J.M., Rodrigues R. 2001. Grupo Bauru: uma unidade continental Cretácea no Brasil - concepções baseadas em dados micropaleontológicos, isotópicos e estratigráficos. Revue de Paleobiologie, 20:245-304. (Ostracods); Santucci & Bertini 2001Santucci R.M., & Bertini R.J. 2001. Distribuição paleogeográfica e biocronológica dos Titanossauros (Saurishia, Sauropoda) do Grupo Bauru, Cretáceo Superior do sudeste brasileiro. Brazilian Journal of Geology, 31:307-315. and Martinelli et al. 2011Martinelli A.G., Rief D., Lopes R.P. 2011. Discussion about the occurrence of the genus Aeolosaurus Powell 1987 (Dinosauria, Titanosauria) in the Upper Cretaceous of Brazil. GAEA Journal of Geoscience, 7:34-40. (Allosaurus) (Batezelli 2015Batezelli A. 2015. Continental systems tracts of the Brazilian Cretaceous Bauru Basin and their relationship with the tectonic and climatic evolution of South America. Basin Research, 29:1-25.).
Figure 3:
Described sections. Botucatu section (A1): Located in the homonymous municipality (Marechal Rondon Highway, km 151), and stratigraphic section with the lithofacies (Gc, Gt, Gm) and profiles (P1, P2); Piratininga section (A2): Located in the homonymous municipality (Bauru-Ourinhos Highway, km 248), and stratigraphic section with the lithofacies (Gm, Gmi) and profiles (P3, P4, P5, P6, P7); Garça section (A3): Located in the homonymous municipality (João Ribeiro de Barros Highway), and stratigraphic section with the lithofacies (Sm, Gm, Fm) and profiles (P8, P9). The identification and description of facies are based on proposals from Miall (1985Miall A.D. 1985. Architectural-element analysis: a new method of facies analysis applied to fluvial deposits. Earth-Science Reviews , 22:261-308. , 1996Miall A.D. 1996. The geology of fluvial deposits. Berlin, Springer-Verlag, 582p.).
Figure 4:
Facies and the macromorphology of paleosol profiles. (A) column with the lithofacies (Gc, Gt, Gm), profiles (P1, P2) and horizons of the Botucatu Section (A1); (B) column with the lithofacies (Gm), profiles (P3, P4, P5, P6, P7) and horizons of the Piratininga Section (A2); (C) column with the lithofacies (Gm, Fm), profiles (P8, P9) and A3 horizons.
Figure 5:
Morphological aspects of paleosol profiles. (A) Horizon base C2 of P (the base does not have CaCO3 cementation indicating if it is a pedogenic calcrete); (B) bioturbations with and without carbonate filler material in the profile 4. The black arrow indicates a rhizolith (a precipitated carbonates tube, which filled former burrows), a common feature in paleosols of the Marília Formation. The rhizoliths are organo-sedimentary structures produced by decomposition and plant root activity (Durand et al. 2010Durand N., Monger H.C., Canti M.G. 2010. Calcium carbonate features. In: Stoops G., Marcelino V., Mees F. (Eds.) Interpretation of micromorphological features of soils and regoliths. Amsterdam, Elsevier, p. 149-194.). The yellow arrow indicates a krotovine (bioturbation mark filled with other materials) on top; (C) the red arrow indicates a large bioturbation (rhizolith) on the Btc horizon profile 5 with a reduction of halos (white) and oxidation (redder feature); (D) bioturbations in the Bt horizon of the A2 section; (E) Rhizoconcretion present in the Marília Formation.
Figure 6:
Structures of the Marília Formation paleosols. (A) Prismatic structure Btkm1 horizon (P7), with carbonate nodules; (B) laminar structure profile 8 (P8); (C) blocky structures Bt horizon (P5), especially lots of bioturbation; (D) details of the blocky structures, and carbonate cementation involving peds (calcan).
Figure 7:
Characteristics of the groundmass. (A) CaCO3 recrystallization process in the C2 horizon (P1), resulting in crystalline pedological features (crystalline pedofeatures) represented by carbonate nodules (yellow arrow); (B) with crossed nicols (NC); (C) simultaneous processes and weathering replacement of the quartz polycrystalline calcite (red arrow) in the Bt1 horizon (P5); (D) with NC. With a polarized light, it is possible to perceive a superimposition process of clayey material (iron oxides) in the carbonate features; (E) bioturbation in the Bt1 horizon (P5) filled by quartz grains (krotovine); (F) with NC; (G) replacement process and bioturbation feature in laminar horizon Bkm1 (P8). There is a change and partial replacement of quartz with microsparitic calcite coating, which is indicated by the yellow arrow. Coating quartz carbonate is a typical feature of soil profiles (Bedelean 2004Bedelean H. 2004. Study on the diagenetic calcareous accumulations in a soil profile from Florestin (Cluj country, Romania). Geologia (Studia Universitatis Babes-Bolyai), 69:75-85.). The red arrow indicates a calcified root mark, common in rizogenic calcrete; (H) with NC; (I) pendant calcite (Pt) in the Btkm horizon (P9) below the quartz grains (Q) indicated by the arrows; (J) with NC; (K) Feature coating in the Bt2 horizon (P5). The yellow arrow indicates coatings with iron oxides around the quartz grains (Q), typical autochthonous pedological feature; (L) with NC.
Figure 8:
Features of the groundmass. (A) Chronology in the Bkm horizon (P1). The chronology revealed that palygorskite (P) precipitated in the paleosol void, as a secondary mineral. The yellow arrow indicates weathered biotite; (B) with NC; (C) crystalline pedofeature, represented by the root mark (rhizolith CaCO3) in the Bk/Ck horizon (P8); (D) Microcodium in the Bkm1 horizon profile 8 (arrows); (E) with NC; (F) pisolite shows concentric rings of iron-containing material (Bt1 horizon of P5), with natural light (LN or PPL). The yellow arrow also shows clay with iron oxides coating the pisolite.
Figure 9:
C1 horizon (P3) SEM. (A) Authigenesis of palygorskite (Pg), coating grains of quartz (Q) and calcite; (B) detailed palygorskite (Pg) in the form of aggregate of entangled fibers coating the quartz grain (Q); (C) the formation of palygorskite (Pg) through changing smectite (E). It is possible to observe palygorskite in the form of aggregate filling the voids intertwined fibers, a typical feature of paleosol (Singer 2002Singer A. 2002. Palygorskite and sepiolite. In: Dixon J.B., Schulze D.G. (eds.). Soil mineralogy with environmental applications. Wisconsin, SSSA Book Series, p. 556-584.).
Figure 10:
XRD patterns with a quantitative analysis using the Rietveld refinement of the profile 3 of the Piratininga (P3C1) section and profiles with the B horizon of the Botucatu (P1Bkm1, P1Bkm2) and Piratininga (P4Bt1) sections.
Figure 11:
XRD patterns with quantitative analysis using the Rietveld refinement of profiles with a B horizon from the Piratininga (A2) and Garça (A3) sections.
Figure 12:
Percentage variation of quartz, calcite and palygorskite in the A1 (Botucatu), A2 (Piratininga) and A3 (Garça) sections of the Marília Formation. The columns on the left (7 m, 17 m and 7 m) of each section (A1, A2 and A3) represent the facie associations and the architectural elements (EA).
Figure 13:
Climate evolution model based on the mineralogy of the profiles for the paleosols of the Marília Formation, Maastrichtian of the Bauru Basin.
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