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The supply of Corumbataí Formation rocks, which occur widely in the State of São Paulo, Brazil, and are used by Santa Gertrudes Ceramic Cluster, is dwindling and prospecting for new deposits is essential. The current study aimed to map and characterize new reserves of ceramic raw materials which would guarantee mineral and economic sustainability of the important concentration of ceramic-processing capability in that area, and thereby contribute to improving and diversifying the range of products manufactured and to promoting a greater presence in the international market. To achieve the proposed objectives, 16 profiles were sampled and the samples were submitted to granulometric analysis by laser diffraction, and the major elements by inductively coupled plasma-mass spectrometry, and the mineralogical compositions of clay samples were determined by X-ray diffraction and ceramic properties. Six lithofacies were identified and grouped into two facies associations: a lower shoreface association comprising massive siltstone (Sm) and laminated siltstone (Sl); lithofacies, and an upper shoreface association comprising heterolithic sandstone (Sh), lenticular sandstone (Sle), intercalated sandstone/siltstone (Si), and altered siltstone (Sa) lithofacies. The lithofacies of the lower shoreface association were more clayey, flux with a significant presence of illite and microcline, and a more uniform granulometry distribution, which made its classification possible, technologically, as stoneware and semi stoneware. The main application of this material is in the production of coatings through the wet milling process. The lithofacies of the upper shoreface association was sandier, had a refractory presence with kaolinite and montmorillonite, and had a less uniform granulometric distribution; technologically, it can be characterized as porous and semi-porous. The main application of this material is in the production of coatings by the dry milling process. The results obtained by facies analysis combined with the geochemical and ceramic properties of the Corumbataí Formation rocks revealed both vertical and lateral variations of the lithofacies, which influence their properties, behavior, and application as ceramic raw materials. [ABSTRACT FROM AUTHOR]

Carbonate reservoirs are of great economic importance due to their frequent association with high permeability and hydrocarbon storage capacity. One of the most significant discoveries of this type of reservoir in recent decades has been the Brazilian Pre-salt. This deep reservoir has unusual depositional features, consisting of a wide variety of textures with different compositions, influenced by diagenetic overprinting that modify most of its mechanical, elastic and petrophysical properties. Despite the marked heterogeneity, these carbonates are characterized by excellent reservoir quality. The objective of this study is to establish a correlation between geomechanical behavior and sedimentary facies and its implications for the definition of flow units in the Barra Velha Formation, the main reservoir of the Brazilian Pre-salt. Thus, using a database from the Buzios field composed of well logs (conventional and advanced), well tests, thin sections, and laboratory petrophysics, geomechanical facies (GMFs) were defined using dynamic geomechanical modeling and an unsupervised algorithm (K-mean clutering), followed by textural classification of sedimentary facies and definition of flow units (FUs) on the decametric scale. These classifications were compared using frequency histograms. The geomechanical model revealed that the in-situ stress state exhibits a dual regime, between normal and strike slip. In addition, it was found that the direction of the maximum horizontal stress is in the NE-SW azimuth. In this context, four geomechanical facies were defined, which showed a notorious variation in mechanical strength. The strongest GMFs consisted mainly of well-cemented Grainstones and Packstones with no apparent porosity or microcrystalline porosity and correlated with the FU with the worst production rates. On the other hand, the weaker GMFs were mainly composed of Grainstones and Spherulistones with high intergranular porosity generated by dissolution processes, with higher risk of pore collapse and correlated with the FUs with the best production rates. However, this classification also identified laminated mudstones with microporosities associated with FUs that act as flow barriers. Geomechanical facies have also been incorporated into reservoir development by evaluating wellbore stability, fault reactivation risk, and brittleness index for future CO 2 injection projects. • Stress regime duality in the Búzios field (Normal to Strike-slip failure regime). • Low to intermediate mechanical strength of Brazilian pre-salt reservoir. • The sedimentary facies show a great variety of textures, and porosities, influencing the geomechanical behavior. • Lateral and vertical variations of the geomechanical properties using K-means clustering defined by facies. • Comparison between flow units and geomechanical facies. [ABSTRACT FROM AUTHOR]

During the Cretaceous, the Brazilian Intracratonic Sanfranciscana Basin was characterised by fluvial and aeolian deposition, whose facies, palaeosols, and stratigraphic architecture indicate significant changes in tectonics and climate. This work proposes a low-frequency sequence stratigraphic model, using the facies and palaeosols distribution as the stratigraphic proxy for identifying variations in the accommodation space, sediment supply, and their relationship with the tectonic and climatic events. The Unconformity U-0 was generated by the extensional tectonic processes during the Gondwana breakup in the Early Cretaceous and marked the initial continental sedimentation. The Lower Cretaceous Sequence SF1 overlies this unconformity, constituted by fluvial and lacustrine deposits. From south to north, the unconformity U-1 truncates the top of the Lower Cretaceous Sequence SF1 and the Precambrian basement, respectively. Overlaying Unconformity U-1 are the Upper Cretaceous volcanic rocks, fluvial, and aeolian deposits of the Sequence SF2. Because of the vertical and lateral changes, Sequence SF2 is divided into two sequences, SF2A and SF2B, separated by the regional Unconformity U-2, representing climatic and tectonic changes in the basin. During the late stage of sedimentation of Sequence SF1, the ratio between accommodation (A) and sediment supply (S) was positive in the south and negative in the basin's north. The evolution of Sequence SF2A records a negative A/S ratio, followed by an abrupt change to a positive A/S ratio in Sequence SF2B, leading to the genesis of the regional erosive surface of Unconformity U-2. Sequence SF2B also records increased humidity from arid climatic conditions, marked by the 3D regional distribution of facies and palaeosols, linked to the climatic changes detected in South America for the Late Cretaceous. • Proposes low-frequency sequence stratigraphy analysis. • The 3D regional distribution of facies and palaeosols approach. • The Brazilian Intracratonic Sanfranciscana Basin. • Variations in the accommodation space, sediment supply, and their relationship with the tectonic events. • Late Cretaceous climatic changes. [ABSTRACT FROM AUTHOR]

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The Upper Cretaceous Bauru Group in south‐east Brazil consists of alluvial strata whose characteristics and distribution indicate a fluvial system developed in a semi‐arid to arid climate. Sections exposed within a 90 000 km2 study area in Minas Gerais State (in south‐eastern Brazil) were evaluated using facies and palaeosol analysis to formulate depositional and pedogenic models that may account for geomorphic and climate features. From east to west, the study succession records a gradual decrease in grain size, an increase in the width/thickness ratio in channels, a decrease in the lateral and vertical connectivity of channel deposits, and an increase in overbank deposits. The fluvial architecture indicates a braided channel belt, ephemeral ribbon–channels, and an unconfined fluvial facies from east to west in the study area. The lateral and vertical distribution of facies, stratigraphic architecture and palaeocurrent data suggest proximal, medial and distal portions of a progradational distributive fluvial system. The sedimentary dynamics were marked by the building and abandonment of channels related to processes of aggradation, vegetation growth and palaeosol generation. Macromorphological and micromorphological analyses have identified pedological and mineralogical features that indicate an arid to semi‐arid climate with a provenance from the north‐eastern part of the basin (Alto Paranaiba Uplift). From the proximal to the distal portions of the distributive fluvial system, the palaeosol development is different. In the proximal portion, the palaeosols are absent or poorly developed, allowing a possible general comparison with the present soil order: Inceptisols and Aridisols. In the medial portion of the fluvial system, the palaeosols are well‐developed and characterized by Bt, Btk, C and Ck horizons (Alfisols, Aridisols, Inceptisols and Entisols). Poorly drained to well‐drained palaeosols from the base to the top in the distal plain (Aridisols and Inceptisols) are associated with geomorphic and hydromorphic changes in the fluvial system due to progradational evolution. The genetic relationship between the fluvial architecture and the palaeosols enhances the understanding that the sedimentation and pedogenesis that occurs in different portions of the distributive fluvial system are related to the tectonic and climatic evolution of the basin. [ABSTRACT FROM AUTHOR]

Flow units (FUs) have been widely used for rock typing in many reservoirs, especially where there is no direct correlation between petrophysical properties and geological characteristics. This scenario is extremely common in carbonate rocks that are likely to be shaped and modified by pedo-diagenetic processes forming heterogeneous reservoirs with geological and petrophysical properties varying in all scales. The present work aimed to test different well-established petrophysical rock-typing methods in complex carbonate reservoirs and integrate them with geological-driven rock classifications. The goal was to find a correlation between facies, diagenesis and the quality of the reservoir as well as understand how different rock-typing methods behave in complex reservoirs. This study was implemented on the carbonates of the Barra Velha Formation which are known for their complexity regarding facies, diagenetic features, and petrophysics. The study was performed in two oilfields of Santos Basin (Brazil) and employed data from 44 wells, including routine core analyses and well logs, along with core and thin section high-resolution images. As a result, 13 facies were identified and grouped into six facies associations representing different zones of a lacustrine environment: Deep Lake, Lower Shoreface, Upper Shoreface, Lower Foreshore, Upper Foreshore, and Backshore. Three rock-typing methods were tested for the flow units identification: FZI, Winland R35 and Aguilera R35. The Barra Velha Formation was subdivided into 4 flow units. All methods reveal that the Deep Lake and Lower Shoreface Facies Associations comprise the poorer reservoirs of the Barra Velha Formation and that the Lower and Upper Foreshore Facies Associations concentrate the best reservoirs. Shrubstones were the facies with the highest R35s and FZIs values followed by the grainstones. The FZI methodology was the most optimistic and Winland R35 the least. Aguilera R35 presented the highest correlation with permeability, proving to be a reliable method for application in complex carbonate reservoirs. The approach and equations obtained in the Pre-salt reservoirs can be employed for different oilfields. Therefore, for a more accurate result, we recommend the calculation of the constants using data from the studied field. • Barra Velha Formation comprises in situ, reworked, and altered facies that were subdivided into 6 facies associations. • The formation was subdivided into 4 flow units based in 3 different rock typing methods: FZI, Winland R35 and Aguilera R35. • FZI had the most optimistic results and Winland R35 the least. Aguilera R35 had the highest correlation with permeability. • Shrubstone and Grainstone are the most frequent facies in flow unit 4, which comprises the best reservoirs of the formation. • The methodology presented in this work can be applied to segment flow units in other locations. [ABSTRACT FROM AUTHOR]

Soils are good indicators of the stability of environmental systems. In meandering river floodplains, they assess river channel morphology, incision process, groundwater level dynamics, and avulsion processes. The morphological properties and physicochemical attributes give gleysols unique characteristics about formation conditions and evolution degrees related to fluvial dynamics, thus allowing elaborate models of floodplain evolution in meandering rivers. This manuscript aimed to analyze the relationship between gleysols evolution and fluvial dynamics, in the quaternary floodplain of a meandering river, in the Mogi Guaçu River basin in the State of Minas Gerais. We described three profiles, in concave and convex margins of the river, identifying facies and considering the morphological characteristics of the gley horizons. Physicochemical analyses, determination of major and minor elements, and oxides were carried out on the samples of horizons and deposits of the profiles. For the characterization of the river channel, morphometric parameters were measured. Concentrations of silica, titanium dioxide, alumina, ferric and manganese oxides, plus the molar relations of provenance (P), leaching (L), parent material (M1 and M2), oxidation (O), hydrolysis (H), and the alteration geochemical index (CIA-K) were determined to compare the profiles pedological evolution. The three analyzed profiles were classified as typic Dystrophic Tb Haplic Gleysol (P1 and P2) and typic Alic Tb Haplic Gleysol (P3) so that the relation silt/clay demonstrated profile 3 to be the most evolved (weathered). Concentrations and behavior of oxides, associated with molar relations and conditions of the surfaces S II and S III of the flat floodplains morphological, demonstrated that the meandering process, with avulsion linked to erosion and deposition, affects gleysols evolution, suggesting genesis with compound or polygenetic profiles. Under a cyclical interpretation, the evolution of gleysol profiles, with truncation and horizon overlaying, reflects processes of avulsion, incision, and floods, as well as are proxies for interpreting the quaternary evolution of the Mogi Guaçu River meandering process. • The meandering process, with avulsion associated with erosion and deposition, influences the evolution of gleysols, providing for the genesis of compound or polygenetic profiles. • The genesis of different pedotypes of gleysols are reflections of the process of avulsion and incision of the river channel. • The Gci, Sh, Sl, Sm, and Fm facies, along with intense mottling in the horizons, demonstrate oscillations in the groundwater level and changes in the channel's energy gradient. [ABSTRACT FROM AUTHOR]

The Late Albian-Early Turonian succession on the Arabian Platform stands out as one of the world's richest hydrocarbon provinces. This study delves into the Seismic Sequence Stratigraphy (SSS) of these successions to unravel reservoir characterization and characterized potential hydrocarbon plays. Utilizing data from five exploration wells, including well logs, selected core data, biostratigraphical information, and chemostratigraphy analysis, alongside a comprehensive 3D seismic volume, enabled the identification of four 3rd-order sequences and multiple 4th-order sequences within the studied successions. Sequence-1 (DS-I), dating back to the Late Albian age, features mudstone and bioclast wackestone in an open marine environment. DS-I is a key sequence, notably witnessing the disappearance of siliciclastic input from west to east in the study area. DS-II (Early Cenomanian) and DS-III (Mid-Cenomanian) were deposited on carbonate platforms with grain-supported facies in shoal and lagoonal depositional environments. A distinct regional unconformity at the Turonian base, evident on seismic sections, aligns with depleted δ18O values on the Cenomanian-Turonian Boundary. The maximum flooding surfaces of DS-I and DS-II are characterized by continuous reflectors with negative amplitude. Furthermore, the lateral grading of reservoir facies and their intercalation with non-reservoir facies within 4th-order sequences suggest that reservoir facies heterogeneity is strongly influenced by depositional processes at this scale. Potential reservoirs, particularly in the Highstand System Tract (HST) of each 3rd sequence, are highlighted, with DC-III's HST standing out, hosting patch reef facies resulting from local tectonic activities and carbonate build-up movements. • High resolution seismic sequence stratigraphy was applied to Reservoir characteristics. • New insight to distinguished petroleum play by using HRSS approaches. • Biostratigraphy and chemostratigraphy analysis to detect Sequence boundaries. • 3rd and 4th sequences were characterized within the Late Albian-Early Turonian successions. • Heterogeneity is strongly controlled by the depositional processes operated at the scale of 4th-order cycles. [ABSTRACT FROM AUTHOR]