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Paleosols are the product of ancient physical, chemical, and biological processes on the Earth's surface and, as such, may record information that can be used to reconstruct the paleoatmospheric and paleoenvironmental conditions under which they formed. In Brazilian continental sedimentary successions, few studies using ancient soils have focused on the relationship between paleopedogenesis and paleoclimate. The Marilia Formation is a 160-m-thick section of the Bauru Basin in which ∼ 66% of the deposits show some evidence of pedogenic modification as paleosols. In this paper, paleosol profiles in the Marilia Formation containing thick calcrete intervals are described and attributed to three pedotypes: Avencas, Monte Alto, and Garça. Macro and microscopic pedogenic features of each pedotype are described in detail. Moreover, the analysis of clay mineralogy, whole-rock geochemistry, and stable-isotope composition are used to define pedogenic processes, paleoclimate proxies, and atmospheric pCO2 estimates. The Avencas pedotype is composed of six polygenetic profiles with different phases of carbonate precipitation, clay illuviation, and biogenic actions. The Monte Alto pedotype is moderately developed and composed of calcic horizons formed mainly by rhizoliths, with higher degrees of calcification and oxidation compared to Avencas profiles. The Garça pedotype is well developed with five polygenetic profiles presenting high carbonate content and low accumulation of clay minerals (CIA-K) and leaching. Estimates of paleoprecipitation and paleotemperature from the studied paleosols using climofunctions of molar ratio of base to alumina, depth of carbonate accumulation, salinization, oxygen composition, and paleosol weathering index proxy (PWI) show values ranging from 242 to 718 mm/yr and 11° to 14°, respectively. Climofunction values suggest a paleoclimate of semiarid to subhumid during deposition of the Marília Formation. The climate data also suggests that during the Maastrichtian, the Bauru Basin was geographically within the Southern Hot Arid Belt zone, though showing strong influence of the lower latitudinal Equatorial Humid belt. Furthermore, atmospheric pCO2 values calculated from pedogenic carbonates may correlate with a cooling interval during the latest Maastrichtian (68.5–66.25 My).

This study discusses the cause of local lithification in sediments from quaternary beach ridges of Paraíba do Sul Deltaic Complex (Rio de Janeiro, Brazil) and its application to the concept of geological heritage. These beach ridges were excavated to construct the Campos - Macaé Canal, opened in the 19th century predominantly by slave labor. A detailed sedimentological, mineralogical and petrological study was performed. The consolidated material consists to fine-grained sandstone with incipient parallel lamination. Kaolinite associated with iron oxides/hydroxides is organized in thin coatings, sometimes forming meniscus and bridges. The heavy mineral assembly of the sandstone is similar to those found in the beach ridges friable samples. The sandstone granulometry increases from east to west along the canal margins and the same pattern is observed in the adjacent beach ridges. We suggest that pedogenic processes acted intensively on Canal margins after its opening, causing mechanical infiltration and translocation of clay minerals, promoting differentiated consolidation of sediments only in that part that was deepened during the excavation. The anthropic action altered the local physiography by exposing the sediments of beach ridges. Therefore, this sandstone should be considered a geological heritage due to its unique occurrence, touristic, historical, scientific and educational value.

The current research investigates the removal of endocrine disruptor compounds (EDC) in the absence and presence of organic matter in aqueous solution and natural water. In addition, the interactions of different fractions of natural organic matter (NOM) and fulvic acid (FA) in 17α-estradiol (EE2), 17β-estradiol (E2), estrone (E1) estriol (E3) and bisphenol A (BPA) were assessed. The interaction experiments between organic matter show that E3 has a higher sorption coefficient (Koc) in FA (0.0921 L mgC−1) with concentrations around 0.753 mg L−1 ± 0.0367. While at NOM, E2 has a major interaction with Koc of 0.0840 L mgC−1 and binding concentration in the range of 0.713 mg L−1 ± 0.0106. The photolysis experiment to 2.5 mg L−1 of initial concentration, with absence of organic matter, shows that EE2, E2, E3 and E1 have high removal with 95, 96, 97% and 80% after 180 min, respectively. On the other hand, the degradation of BPA at the same concentration was 53%. In the presence of NOM (1.0 mg L−1), E1 degradation was around 2 times faster than aqueous solution and FA (1.0 mg L−1). The results of E1 degradation between NOM with 1.0 mg L−1 and 5.0 mg L−1 had removal of 77 and 69%, respectively. In the natural water, the degradation of E2 and E3 was much faster than aqueous solution. These results could extend our knowledge on the photodegradation behaviours of EDC in natural waters.

Aptian siliciclastic onshore deposits of the Mucuri Member are important reservoirs in the Espirito Santo Basin (eastern Brazil). A detailed quantitative petrographical and textural analysis of well core samples was performed in order to unravel their depositional processes and conditions, in relation to previously proposed depositional models. The results allowed differentiation between two groups of sandstone samples, characterized by different textural characteristics associated to different depositional processes and environments within the Mucuri depositional system. Fluvial sandstones are represented by medium- to coarse-grained, poorly sorted arkoses, rich in plutonic rock fragments and feldspar grains, mainly transported by traction. Coastal-lacustrine sandstones correspond to very fine- to fine-grained, moderately sorted micaceous arkoses, mainly transported in suspension. The application of a discriminant function based on grain-size parameters validated previously proposed depositional settings for the studied sample groups. The combination of grain-size and shape data revealed differences in hydraulic equivalence and shape between grains from different depositional settings. In terms of hydraulic equivalence, micas in the fluvial sediments present lower settling velocity values, in contrast to the relatively large mica grains in the coastal sediments, which are hydraulically equivalent with the associated quartz and feldspar grains. The results of this study provide key information regarding depositional conditions (transportation mechanisms, grain-settling velocity and mineral hydraulic fractionation) at the margins of the Aptian pre-salt system, which can constrain the hydrological conditions and the sediment type available for distal lacustrine areas.

Records of shallow-marine ramps with the mixing of carbonate and siliciclastic sediments are common throughout the geological time. All these records have pure carbonate and pure siliciclastic deposits as end members, occurring contemporaneously in distinct depositional regions along the ramp, and transitional hybrid facies between them. The two end member can mix in different scales and can alternate in time due to climatic changes and regressions and transgressions. This work presents a detailed reconstruction of a Mesoproterozoic storm-dominated mixed carbonate-siliciclastic ramp composed of hybrid sediments and whithout the presence of pure siliciclastic or carbonate deposits, a rare example in the geological record. Based on a high resolution logged section (in 1:20 scale) and qualitative thin sections, eleven lithofacies were identified and grouped into three lithofacies associations (offshore, offshore transition and shoreface), which are stacked vertically forming a transgressive–regressive cycle. This faciological distribution indicates a low relief ramp with wide microbial colonization from shallow to relatively deep waters (below storm-wave base level). In offshore low-energy distal areas, microbial mats spread laterally over large distances with little or no interference from currents, while in the offshore transition the morphology of the bioherms is shaped by currents induced by waves. In turn, the high wave energy in the shoreface inhibits the formation of stromatolites, restricting their occurrence to thin layers of microbial carpets or intraclastic lags. The mixing occurs in compositional scale and is relatively homogeneous along the whole logged interval, independent of the shifts in lithofacies or lithofacies associations. This compositional homogeneity is linked to the wide distribution and regularity in the input of siliciclastic sediments during the sedimentary accumulation. Strong currents induced by storms allow the transport and mixing of siliciclastic sediments with carbonate grains generated in the basin during fair-weather periods.

O objetivo desse trabalho é analisar as mudanças ocorridas na grade curricular da Geologia da UFRJ frente as Diretrizes Curriculares Nacionais para identificar quais serão os possíveis impactos no perfil do egresso. Para isso foi realizada uma análise comparativa e qualitativa das grades curriculares e entrevistas com docentes. As mudanças curriculares consistiram: (1) na diminuição de horas teórico-práticas em disciplinas; (2) na inclusão de 420 horas de extensão; (3) na inclusão das disciplinas de Estágio Supervisionado e de Saúde e Segurança; (4) na inclusão de horas teóricas nas disciplinas Geologia de Campo. Dois impactos foram identificados: (1) melhor preparação para o mercado de trabalho, gerando geólogos mais autônomos e atentos as questões sociais e (2) prejuízo na formação básica conceitual de modo a dificultar a resolução de problemas geológicos complexos. Sugere-se acompanhamento semestral do processo de implementação para auxiliar na detecção de inconsistências e no planejamento das futuras revisões.

In arid and semi-arid climates, soil development is strongly influenced by seasonal patterns and biogenic activity, and often results in pervasive pedogenic horizons consisting of highly concentrated carbonate. In Brazil, such horizons enriched in calcium carbonate are common and relatively well-studied in paleosols of the Upper Cretaceous Marilia Formation. However, detailed analyses on the sequence of mineral precipitation phases and the role of organisms in these processes are still lacking. The present work describes eight argillic and calcic horizons characterized by different degrees of carbonate accumulation. Argillic horizons show translocation clay structures and weak to moderate cementation by calcium carbonate. Calcic horizons contain moderate to high carbonate accumulations ranging from powdery coatings to nodular masses of micrite. Carbonate distribution in these horizons is preserved largely as carbonate-cemented macropores produced by such ichnofossils as Planolites, Taenidium, Naktodemasis, Skolithos, Palaeophycus and calcareous rhizocretions. Moreover, stable isotope data, respired soil CO2 function, and cathodeluminescence (CL) of the paleosol samples were used to evaluate soil paleovegetation, paleoproductivity, and the distinctive stages of calcite precipitation. Stable isotopic analysis suggests that paleovegetation cover in the paleosols was predominantly C3-photosynthsizing plants. The relationship between bioturbation indices and soil respiration suggests a positive pattern of paleoproductivity controlled by higher moisture conditions and the increased activity of soil fauna. Finally, CL imaging shows that there were multiple stages of carbonate precipitation with both α-type and β-type fabrics that are interpreted as abiotic and biotic processes during pedogenesis.

In this study, new activated carbons from coffee, wood and apple pomace wastes were synthesised by pyrolysis and subsequent acid wash under reflux. These materials were characterised by a combination of spectroscopic and chemical techniques including SEM, BET, TGA, WCA, FT-IR, and pH PZC . The carbons prepared were applied as adsorbents in the removal of 17β-estradiol (E2) from aqueous solutions. In general, the results of characterisation of the manufactured adsorbents showed that the surfaces properties size and pore distribution are dependent on the precursor used. Furthermore, the leaching of inorganic compounds with HCl causes structural modification, which leaves the materials more active in interactions with 17β-estradiol. The highest percentage of E2 removal was obtained for samples from coffee and wood wastes, where the percentage of E2 removal was 100%, with exception of CS sample. For activated carbon from apple pomace, the activation process increased its adsorption capacity about two-fold (39.2–81.6%) (E2 = 0.500 mg L −1 ). In addition, amount of E2 adsorbed were: CS, ACCSA7, ACCSA10 and ACM = 0.33 mg g −1 ; AP = 0.13 mg g −1 ; ACAP7 = 0.27 mg g −1 (E2 = 0.500 mg L −1 ) and ACCSA7, ACCSA10 and ACM = 5.07 mg g −1 ; CS = 4.95 mg g −1 ; AP = 2.05 mg g −1 and ACAP7 = 2.35 mg g −1 (E2 = 7.60 mg L −1 ). These aspects demonstrate the potential of activated carbon from agroindustrial wastes as new adsorbents for the removal of 17β-estradiol in aqueous solution.

Abundant early diagenetic siderites occur as spherulites and rhombohedral microcrystalline and macrocrystalline crystals in the cores of the 2-MU-1-RJ well, drilled in the Paraiba do Sul Deltaic Complex, Rio de Janeiro (Brazil). The host sediments of the siderites are siliciclastic, hybrid, and carbonate deposits. Intense pedogenetic processes affected the siliciclastic sediments immediately after deposition, comprising clay illuviation, plants bioturbation, feldspar dissolution, and iron oxide/hydroxide precipitation. Siderite and pyrite are the main diagenetic constituents. The other diagenetic products are kaolinite, smectite, argillaceous and carbonate pseudomatrix, quartz overgrowths, diagenetic titanium minerals, jarosite, and iron oxides/hydroxides. Early diagenetic siderites were separated into four groups based on their elemental and stable isotopic composition, as well as on their paragenetic relationships with the other constituents and with the host sediments. Spherulitic to macrocrystalline siderites from group 1 are almost pure (average: 94.7 mol% FeCO3; 1.2 mol% MgCO3; 2.3 mol% CaCO3; 1.8 mol% MnCO3) and precipitated from meteoric porewaters in continental siliciclastic rocks under suboxic conditions (δ18Ovpdb values range in − 10.28 to − 5.57‰ and the δ13Cvpdb values in − 12.68 to − 4.33‰). Microcrystalline rhombohedral siderites from group 2 have zonation due to substantial Ca and Mg substitution (core average: 78.5 mol% FeCO3; 4.2 mol% MgCO3; 15.7 mol% CaCO3; 1.6 mol% MnCO3; edge average: 74.0 mol% FeCO3; 9.2 mol% MgCO3; 15.6 mol% CaCO3; 1.1 mol% MnCO3), and δ13Cvpdb and δ18Ovpdb values of + 0.17‰ and − 1.96‰, precipitated from marine porewaters in packstones/wackestones under methanogenic conditions. The group 3 is represented by irregular spherulitic siderites with moderate Ca and Mg substitutions (average: 80.2 mol% FeCO3; 7.9 mol% MgCO3; 11.3 mol% CaCO3; 0.6 mol% MnCO3), with δ18Ovpdb values ranging from − 5.96 to − 7.61‰ and δ13Cvpdb values ranging from − 5.15 to − 10.41‰. The group 4 microcrystalline siderites are magnesium-rich (average: 57.3 mol% FeCO3; 31.4 mol% MgCO3; 9.6 mol% CaCO3; 1.7 mol% MnCO3; δ13Cvpdb + 1.43‰ and δ18Ovpdb − 14.09‰). The group 3 and 4 siderites were formed from brackish porewater under suboxic conditions in hybrid and siliciclastic rocks. These variations in siderites are probably related to the Paraiba do Sul River dynamics, to sea level changes and to climatic variations that took place during the Quaternary.

The petrologic analyses of 40 thin sections from two wells located in Atalaia High, offshore of Sergipe Sub-Basin, allowed the identification of primary composition and diagenetic patterns of Barra de Itiuba Formation. The original detrital compositions included arkoses, sublithic, and lithic sandstones. The main diagenetic processes observed were: compaction of metamorphic rock fragments and mud intraclasts, generating pseudomatrix; precipitation of quartz and feldspar overgrowths and outgrowths, cementation and grain replacement by kaolinite; dolomite and ferrous dolomite/ankerite; pyrite; iron oxides and hydroxides; and diagenetic titanium minerals, in addition to dissolution phases during eo-, meso- and telogenesis. The macroporosity in the two studied wells is primary intergranular, but there is secondary porosity due to dissolution of primary and diagenetic constituents, as well as fracture porosity. Thirteen reservoir petrofacies were defined and grouped into four reservoir petrofacies associations. They reflect the reservoir quality in microscale: good, medium and low-quality and non-reservoir. The good-quality is characterized by average total porosity greater than 15%, whereas the medium shows average total porosity greater than 7%. Low-quality presents average total porosity between 1 and 4%, and the non-reservoir has an average total porosity consistently less than 1%. Overall, the studied reservoirs consist on low-quality and non-reservoir rocks, which are intercalated with levels of medium- and good-quality. The loss of original porosity was mainly due to mechanical compaction (generating pseudomatrix), and cementation by kaolinite and dolomite. Preservation of primary porosity was favored by the presence of quartz overgrowths.