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We investigate the crustal architecture and structural domains of the Campos rifted margin in southeastern Brazil, focusing on rifting evolution and segmentation. Based on 2‐D and 3‐D seismic reflection interpretation and potential field modeling, our results reveal an along‐strike variability, in terms of margin architecture and magmatism, that segments the basin into three main sectors from south to north. Through the analysis of seismic reflection profiles, we interpret this lateral variability as a product of lower‐ to upper‐plate alternations and different magmatic inputs. We propose the Southern Campos margin to represent a lower‐plate tectonic setting, where the distal domain is characterized by the formation of the here named Gávea Supradetachment Basin associated with the development of a metamorphic core‐complex. The Central Campos margin is characterized by a massive residual block, representing an upper‐plate setting, with exhumation of different crustal levels in the distal domain. Our analysis suggests that the Central Campos sustained a high magmatic input throughout the rift evolution, supporting the interpretation of Seaward Dipping Reflectors and a magmatic crust in a transitional domain. The Northern Campos margin also represents an upper‐plate setting, but characterized by a progressively delaminated crust. Finally, we compare the Brazilian margin architecture with the conjugate Angola margin, discuss the role of transfer zones in the segmentation and propose along‐strike variations in the volume of magmatism. Key Points: The architecture of the Campos rifted margin shows along‐strike variations interpreted as a result of lower to upper‐plate alternationsThe Vitória‐Colatina Transfer Zone played a major role in margin segmentation, accommodating the lateral change in structural styleThe Campos margin shows lateral variations in the volume of magmatism, with alternations from less to more magmatic settings along‐strike [ABSTRACT FROM AUTHOR]

The Coqueiros Formation, a strategic stratigraphic unit within the Lagoa Feia Group (LFG) in the Campos Basin offshore Brazil, is known for its lacustrine carbonate deposits, which include both organic-rich shales and economically important "coquina" reservoirs. While coquina facies are widely recognized as reservoirs, the source-rock potential of the intercalated shales remains relatively underexplored. This study aims to characterize the mineralogy and thermal maturity of the Coqueiros Formation to assess its potential as a source rock, using a multi-technique approach integrating X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Raman spectroscopy analyses of shale samples from two wells: 3-BP-11-RJS and 6-DEV-18P-RJS. XRD analyses revealed a heterogeneous mineralogy dominated by carbonates (calcite and dolomite) and quartz, with significant contributions from clay minerals and trace minerals such as pyrite and barite. SEM imaging revealed a heterogeneous fabric with grain size, morphology, and porosity variations, reflecting a dynamic lacustrine depositional setting influenced by storm events and fluctuations in terrigenous input. The presence of authigenic minerals, as reported in other studies, such as saddle dolomite, mega-quartz, and various sulfides, provides evidence for hydrothermal alteration, likely related to Late Cretaceous magmatic activity in the Campos Basin. Raman spectroscopy yielded equivalent vitrinite reflectance (Ro%) values consistently exceeding 1.00, ranging from 1.03 to 1.40, indicating that the organic matter in the Coqueiros Formation shales has attained a high thermal maturity level, surpassing the oil window and reaching the condensate wet gas zone. The mineralogical and equivalent maturation data presented herein provide a valuable foundation for future studies, highlighting the complexity and heterogeneity of the Coqueiros Formation and its potential significance as a source rock within the Campos Basin petroleum system. [ABSTRACT FROM AUTHOR]

The Santos Basin in Brazil has witnessed significant oil and gas discoveries in deepwater pre-salt since the 21st century. Currently, the waters in eastern Brazil stand out as a hot area of deepwater exploration and production worldwide. Based on a review of the petroleum exploration and production history in Brazil, the challenges, researches and practices, strategic transformation, significant breakthroughs, and key theories and technologies for exploration from onshore to offshore and from shallow waters to deep–ultra-deep waters and then to pre-salt strata are systematically elaborated. Within 15 years since its establishment in 1953, Petrobras explored onshore Paleozoic cratonic and marginal rift basins, and obtained some small to medium petroleum discoveries in fault-block traps. In the 1970s, Petrobras developed seismic exploration technologies and several hydrocarbon accumulation models, for example, turbidite sandstones, allowing important discoveries in shallow waters, e.g. the Namorado Field and Enchova fields. Guided by these models/technologies, significant discoveries, e.g. the Marlim and Roncador fields, were made in deepwater post-salt in the Campos Basin. In the early 21st century, the advancements in theories and technologies for pre-salt petroleum system, carbonate reservoirs, hydrocarbon accumulation and nuclear magnetic resonance (NMR) logging stimulated a succession of valuable discoveries in the Lower Cretaceous lacustrine carbonates in the Santos Basin, including the world-class ultra-deepwater super giant fields such as Tupi (Lula), Mero and Buzios. Petroleum development in complex deep water environments is extremely challenging. By establishing the Technological Capacitation Program in Deep Waters (PROCAP), Petrobras developed and implemented key technologies including managed pressure drilling (MPD) with narrow pressure window, pressurized mud cap drilling (PMCD), multi-stage intelligent completion, development with Floating Production Storage and Offloading units (FPSO), and flow assurance, which remarkably improved the drilling, completion, field development and transportation efficiency and safety. Additionally, under the limited FPSO capacity, Petrobras promoted the world-largest CCUS-EOR project, which contributed effectively to the reduction of greenhouse gas emissions and the enhancement of oil recovery. Development and application of these technologies provide valuable reference for deep and ultra-deepwater petroleum exploration and production worldwide. The petroleum exploration in Brazil will consistently focus on ultra-deep water pre-salt carbonates and post-salt turbidites, and seek new opportunities in Paleozoic gas. Technical innovation and strategic cooperation will be held to promote the sustainable development of Brazil's oil and gas industry.

The Santos Basin in Brazil has witnessed significant oil and gas discoveries in deepwater pre-salt since the 21st century. Currently, the waters in eastern Brazil stand out as a hot area of deepwater exploration and production worldwide. Based on a review of the petroleum exploration and production history in Brazil, the challenges, researches and practices, strategic transformation, significant breakthroughs, and key theories and technologies for exploration from onshore to offshore and from shallow waters to deep--ultra-deep waters and then to pre-salt strata are systematically elaborated. Within 15 years since its establishment in 1953, Petrobras explored onshore Paleozoic cratonic and marginal rift basins, and obtained some small to medium petroleum discoveries in fault-block traps. In the 1970s, Petrobras developed seismic exploration technologies and several hydrocarbon accumulation models, for example, turbidite sandstones, allowing important discoveries in shallow waters, e.g. the Namorado Field and Enchova fields. Guided by these models/technologies, significant discoveries, e.g. the Marlim and Roncador fields, were made in deepwater post-salt in the Campos Basin. In the early 21st century, the advancements in theories and technologies for pre-salt petroleum system, carbonate reservoirs, hydrocarbon accumulation and nuclear magnetic resonance (NMR) logging stimulated a succession of valuable discoveries in the Lower Cretaceous lacustrine carbonates in the Santos Basin, including the world-class ultra-deepwater super giant fields such as Tupi (Lula), Mero and Buzios. Petroleum development in complex deep water environments is extremely challenging. By establishing the Technological Capacitation Program in Deep Waters (PROCAP), Petrobras developed and implemented key technologies including managed pressure drilling (MPD) with narrow pressure window, pressurized mud cap drilling (PMCD), multi-stage intelligent completion, development with Floating Production Storage and Offloading units (FPSO), and flow assurance, which remarkably improved the drilling, completion, field development and transportation efficiency and safety. Additionally, under the limited FPSO capacity, Petrobras promoted the world-largest CCUS-EOR project, which contributed effectively to the reduction of greenhouse gas emissions and the enhancement of oil recovery. Development and application of these technologies provide valuable reference for deep and ultra-deepwater petroleum exploration and production worldwide. The petroleum exploration in Brazil will consistently focus on ultra-deep water pre-salt carbonates and post-salt turbidites, and seek new opportunities in Paleozoic gas. Technical innovation and strategic cooperation will be held to promote the sustainable development of Brazil's oil and gas industry. [ABSTRACT FROM AUTHOR]

To gain a better understanding of the mechanisms underlying spatial heterogeneity in ichthyoplankton communities in the SW Atlantic, we examined for the first time the latitudinal and continental shelf–slope gradients in ichthyoplankton structure and oceanographic features in the Campos Basin during the relaxation phase of coastal upwellings (late autumn to early winter). This region, located on SE Brazil's continental margin, is the most productive offshore oil basin in the country and has ecological relevance owing to the existence of areas that experiences mesoscale (tens to hundreds of kilometers) processes (eddies, filaments, and upwelling) caused by the interaction of continental shelf and slope circulation with deep water masses. The present study collected a total of 3892 fish eggs and 10,030 larvae from 36 sampling stations, averaging 22 eggs per 100 m3 and 56 larvae per 100 m3. A total of 250 taxa (5 for fish eggs and 248 for larvae) were identified, encompassing 80 families and 145 genera. Species distribution exhibited a considerable degree of spatial variability, which was related mostly to hydrological characteristics. In general, greater densities were associated with higher nutrient concentrations areas. Through distance‐based Redundancy Analysis, some discriminating species were found to associate with certain areas of the continental shelf characterized by colder temperatures. The ichthyoplankton distribution patterns suggested a potential influence from mesoscale oceanographic fronts, specifically those that induce upwelling of the cold and nutrient‐rich South Atlantic Central Water. Nonetheless, the methodologies used in this study faced challenges in distinctly identifying these processes. [ABSTRACT FROM AUTHOR]

The study of disarticulated ossicles of recent sea cucumbers from Campos Basin, Rio de Janeiro, Brazil, from various Holocene strata, obtained by micropaleontological methods, resulted in the identification of at least eight holothurian taxa, belonging to the five of the seven orders of Holothuroidea: Apodida (Synaptidae, Chiridotidae), Dendrochirotida (Psolidae and Cucumariidae), Holothuriida (Holothuria), and Molpadiida (Molpadiidae, Eupyrgidae). Our paper endorses the importance of studies of recent fauna based on isolated ossicles for taxonomy, biostratigraphy, and ecology. This study represents the first effort at the study of recent fauna of sea cucumbers based on the analysis of preserved ossicles in marine sediments. [ABSTRACT FROM AUTHOR]

Abstract Santonian-Campanian tuffaceous siltstone, epiclastic siltstone, arkose, and fossiliferous mudstone occur in a 45-m-thick section of well 1-BRSA-37-RJS drilled in the southern Campos Basin, offshore SE Brazil. Well log data and petrographic and lithogeochemical data obtained from cutting samples were used to propose a schematic model of the volcano's sedimentary paleoenvironment. The volcaniclasts in the tuffaceous siltstone and epiclastic siltstone are scoria basalts, typical of spatter cones associated with monogenetic fields worldwide. The combination of these features with the petrographic ones of the arkoses found in the same well interval is likely to be related to volcaniclastic processes taking place on the continental shelf. Ratios between the immobile trace elements of the volcaniclastic rocks can be explained by mixing between sources in the upper continental crust adjacent to southern Campos and the scoria basalts extruded in the monogenetic fields. The little differentiated, olivine-rich basalts extruded from the scoria and spatter cones suggest a rising asthenosphere mantle extending from hundreds of kilometers eastwards till southern Campos in the Santonian-Campanian. This may have resulted in regional discordances in the Santonian, both in the Campos and Santos basins, and also places the petroleum systems in the southern Campos Basin under the thermal influence of such a rising asthenosphere in the Santonian-Campanian.

Santonian-Campanian tuffaceous siltstone, epiclastic siltstone, arkose, and fossiliferous mudstone occur in a 45-m-thick section of well 1-BRSA-37-RJS drilled in the southern Campos Basin, offshore SE Brazil. Well log data and petrographic and lithogeochemical data obtained from cutting samples were used to propose a schematic model of the volcano's sedimentary paleoenvironment. The volcaniclasts in the tuffaceous siltstone and epiclastic siltstone are scoria basalts, typical of spatter cones associated with monogenetic fields worldwide. The combination of these features with the petrographic ones of the arkoses found in the same well interval is likely to be related to volcaniclastic processes taking place on the continental shelf. Ratios between the immobile trace elements of the volcaniclastic rocks can be explained by mixing between sources in the upper continental crust adjacent to southern Campos and the scoria basalts extruded in the monogenetic fields. The little differentiated, olivine-rich basalts extruded from the scoria and spatter cones suggest a rising asthenosphere mantle extending from hundreds of kilometers eastwards till southern Campos in the Santonian-Campanian. This may have resulted in regional discordances in the Santonian, both in the Campos and Santos basins, and also places the petroleum systems in the southern Campos Basin under the thermal influence of such a rising asthenosphere in the Santonian-Campanian. [ABSTRACT FROM AUTHOR]

The petrophysical characterization of reservoirs requires the identification of sedimentary facies based on the integration of geophysical well logs and rock analyses in the laboratory, which is one of the significant challenges for the petroleum industry. In this work, laboratory analysis results were linked to quality controls of data pre-processing in a new workflow by integrating several techniques. The wells studied were zoned and laterally correlated based on electrofacies characteristic core analysis and petrographic descriptions. This integration resulted in a modeled geologic section for the Namorado Sandstone in the Campos Basin of southeastern Brazil, created based on various data from each well. The borehole NA2 was selected as the key wellbore after creating this section. The logs from this borehole were then analyzed to separate the permo-porous (reservoirs) and non-porous (non-reservoirs) horizons. The zones containing water and hydrocarbons in the permo-porous sections of interest were split along the wells. Subsequently, the identified sectors were interpreted using petrophysical techniques to confirm the preliminary categorization. After combining all quantitative products to quantify the porous layers capable of producing mobile oil, the cut-off factors were introduced. The next step was determining the parameters of the Archie equation, the amount of clay present, and the water saturation from core descriptions, which led to the discovery of deep laminated sandstones. The results strongly correlate with lithology, geological facies, borehole logs, and petrophysical laboratory data. Based on these findings, it is evident that the clay concentration is the primary factor influencing the oil saturation in this reservoir. [Display omitted] • Petrophysical characterization. •Namorado Sandstone. •Campos Basin, Southeastern Brazil. •Analysis of a multi-borehole database. •Modern workflow used. •Integrating several techniques. [ABSTRACT FROM AUTHOR]

The classic fill‐and‐spill model is widely applied to interpret topographic controls on depositional architecture and facies distributions in slope successions with complicated topography. However, this model implies a constant topographic configuration over the lifespan of a turbidite system. In contrast, the impact on patterns of erosion and deposition above dynamic slopes whose topographic configuration varies spatially over time remains poorly investigated. Here, using high‐resolution 3D seismic reflection data and more than 100 wells from a 40 km long stepped slope system (Campos Basin, offshore Brazil), we document the evolution of a sand‐prone turbidite system active during the Oligocene–Miocene transition. This turbidite system was influenced by vertical and lateral deformation, and we propose a new stratigraphic model to explain the resultant depositional architecture. Two depocentres were identified as steps, with channels on the proximal step, and channel–lobe complexes on the distal step, bounded by sediment bypass‐dominated ramps. Lateral stepping of channels on the proximal step, and oblique stacking of the down‐dip lobe complexes, each cut by through‐going channels, indicate multiple fill‐and‐spill cycles. A persistent north‐east‐ward stepping and thickening on the steps are interpreted to reflect lateral tilting of the seafloor driven by salt tectonics. The dynamic substrate prevented the establishment of a single long‐lived conduit across the proximal step, as recorded in systems with fixed topographic configurations. The filling of through‐going channels with mud at the end of each cycle suggests waxing‐to‐waning sediment supply cycles and periods of sand starvation when the lateral tilting dominated and drove avulsion of the feeder channels towards topographic lows. This study demonstrates that subtle dynamic slope deformation punctuated by discrete sediment supply cycles results in complex stratigraphic patterns with multiple phases, and multiple entry and exit points. Repeated cycles of fill‐and‐spill, tilt‐and‐repeat are likely to be present in other stepped slope systems. [ABSTRACT FROM AUTHOR]

The Campos and Santos Basins have been a focus of subsurface studies since the discovery in 2006 of large accumulations of hydrocarbons in the Early Cretaceous rift and post‐rift strata below Aptian evaporites. In this study, regional 2D seismic lines, a 3D seismic survey and well data were interpreted to reconstruct the tectono‐stratigraphic evolution of the rift and post‐rift stages in the northern sector of the Campos Basin. Detailed 3D seismic interpretation and geological modelling were used to subdivide the pre‐salt sedimentary record. This revealed a diachronous strain distribution along the Guriri Fault System (GFS), a roughly NE‐SW striking fault‐bounded horst that was a focus of rift‐related deformation. The syn‐rift succession is interpreted to be the product of two episodes of rifting (RP1 and RP2) with contrasting fault activity patterns and lithostratigraphy. Volcaniclastics and coarse siliciclastics of RP1 were deposited under WNW‐ESE transtension that formed discontinuous half‐grabens followed by extensive erosion and tectonic inversion. Structurally controlled bioclastic rudstones and hybrid deposits characterize RP2 and were deposited in elongated half‐grabens that delimit the GFS horst, which developed under an NW‐SE extension. Deposition under increasingly less tectonically active transitional and post‐rift stages dominated by thermal subsidence gradually led to the healing of the rift‐related structural relief. Selective reactivation of rift faults testifies active tectonic inversion through compression from immediate post‐rift throughout evaporite deposition. These interpretations are put into the context of recent geochronological data of onshore dyke emplacement and the new age constraints for the end of deposition of the pre‐salt sequence. Therefore, we propose an earlier onset on rifting in the Campos Basin, at the Berriasian. [ABSTRACT FROM AUTHOR]

The discovery of a worldclass pre-salt petroleum province in the southeastern Brazilian margin led to an enormous interest in studying tectonic features that may control oil accumulation in rift settings. In the south-central Campos Basin, a dataset of 2D and 3D surveys were integrated with magnetic and gravimetric maps, along with wellbore data, to characterize the evolution of fault systems and their role in the distribution of pre-salt deposits. As a result, a transfer zone, here called Espadarte Transfer Zone (ETZ), was recognized, and its structural architecture, kinematics and evolution through time were interpreted. The ETZ is delimited by overlapping faults, with opposite, divergent dips, strike N20-40E, resulting in a basement high expressed by an N30E elongated horst placed between two half-grabens. In the study area, synthetic normal faults dominate basin geometry in a down-to-basin fashion; however, during the Early Barremian rifting the ETZ high was formed due to the development of antithetic master faults near and along its western border. Those counterregional fault pattern, together with their down-to-basin counterparts, originated a topographic change so controlling the pre-salt stratigraphy on both sides and above the basement high during successive phases of deformation and deposition. Apparently, the deformation migrated eastward as shown by the distribution of the syn-rift sequences preserved in the adjacent half-grabens. In a first approach, the Espadarte Transfer Zone is characterized in mapview by an elongated horst limited by NNE-oriented synthetic and antithetic master faults. Internally, the transfer zone is characterized by an en échelon array of closely-spaced, NE-trending overlapping faults, obliquely-oriented to the basement high, indicative of a left-lateral trantension during rifting. Therefore, negative flower-structures might be interpreted in seismic sections across some of the overlapping faults. Besides the characterization of the ETZ, we compare its geometry and kinematics with many other transfer zones worldwide, and we find many structural similarities. Finally, we propose that the ETZ has a regional relevance in the context of the south Campos Basin, since it composes a segment of a broad tectonic feature - the Araruama Transfer Zone, along which a left-lateral transtension is observed. • The Espadarte Transfer Zone(ETZ) is located in the south portion of the Campos Basin. • The ETZ was formed in the lower Barremian, during the syn-rift phase. • The ETZ shows oblique left-lateral kinematics characterized by en échelon pattern. • The interpretation of negative flower structures is consistent with a transtensional zone. • The ETZ is a segment of the Araruama Transfer Zone. [ABSTRACT FROM AUTHOR]

Three new species of Microlaimus are described from the continental shelf of the Campos Basin, southwest Atlantic, Brazil. Microlaimus campiensis sp. n. differs from all other species in the presence of two anterior testes, slender spicules with enlarged proximal ends, 7-11 pre-cloacal papilliform supplements, and females with a pair of constriction structures, one on each branch of the ovary. Microlaimus alexandri sp. n. shows sexual dimorphism in the size of the amphidial fovea, which occupies 100% of the diameter of the corresponding area in the male; the buccal cavity provided with five teeth and a slightly cuticularized cuticular ring. Microlaimus vitorius sp. n. has four longitudinal-lateral rows of glands associated with small pores, one seta and three pores small pre-cloacal, and the gubernaculum has a triangular base. An amendment to the diagnosis of the genus is proposed, where the number of teeth was modified. [ABSTRACT FROM AUTHOR]

The basins of Campos and Santos, the most important offshore oil reserves in Brazil, hold potential for being the largest offshore oil exploration fields in the next decades, mainly due to the oil located in the pre-salt layer. This region presents real conditions for the occurrence of intense atmospheric events added to the high velocity of the meanders of the Brazilian current. However, the increasing risk of accidents and damage in the region has been the subject of concern and discussion. The risks in the basins of Campos (2011) and Santos (2012) may not exhibit the the same potential for disastrous events as do those in the oil fields of Alaska and of the Gulf of Mexico, but accidents in these areas are not unlikely, as already evidenced by previous accidents under similar operating conditions (e.g. Chevron Platform accident in Campos Basin, RJ, Brazil, 2011). This paper highlights discussion of the multidisciplinary and substantial environmental features in oil exploration fields along the Brazilian coast based on Semi-Systematic Review methodology. The aspects evaluated cover not only geological traits, oceanic and meteorological circulation, but also current oil production, the most significant oil spill accidents recorded up to 2019 and the discussion about some current levels of seawater contamination.

Igneous rocks are widely developed in many hydrocarbon-bearing sedimentary basins in Brazil, and some igneous rocks play positive roles in the oil and gas accumulation process. But so far, no industrial oil or gas flow is discovered in igneous rocks in Brazilian onshore basins. At present, in some literatures published by some researchers, cases of igneous reservoirs in Brazil are inaccurate. The lithology of reservoirs in the Igarape Cuia oil and gas field, the oil and gas field of Urucu and the Barra Bonita gasfield, were previously thought to be volcanic rocks, but now are clastic rocks according to studies, and the igneous rocks in these three oil and gas field can only be acted as indirect and direct cap rocks. Furthermore, igneous rock reservoirs in the Campos Basin and Santos Basin in the Brazilian offshore are briefly analyzed. The representative Badejo oilfield in the Campos Basin has igneous rock reservoirs dominated by basalts which are intercalated with thin layers of volcaniclastic and sedimentary rocks, the storage space are vesicules, fractures and vugular pores, and the porosity of hydrocarbon bearing interval basalt reservoirs ranges from 10% to 15%. In addition, for the Santos Basin, igneous rocks in this basin are dominated by basic rocks, some alkaline intrusive rocks develop good micro spaces, mainly crystal moldic pores, inter- and intra-crystal dissolution pores and fractures, better reservoir intervals are often concentrated such as at sections near to unconformity surfaces and can have porosity of 6%–9% or higher; local pre-salt igneous rock reservoirs in the Santos Basin have the necessary conditions for hydrocarbon accumulation and it will be a new target layer for hydrocarbon exploration.

Block A in the southern Campos Basin in the deep water of Brazil has complicated pre-salt structures as a result of the Late Jurassic tectonic activity. Based on new 3D seismic and drilling data, the geological attributes, fault development and tectonic evolution of pre-salt in block A were reviewed. Four seismic reflection layers and three seismic sequences were identified in the pre-salt section. Block A also experienced three stages of tectonic evolution, including rifting, erosion and tilting as well as thermal subsidence. Additionally, NE and NNE normal faults are well developed in this region. Tectonic activity also resulted in a NW-SE transform fault in the region and this controlled the distribution of normal faults. Finally, the influence of tectonic activity on hydrocarbon distribution was discussed and it is expected to provide scientific basis for the pre-salt exploration activities in block A and Campos Basin.

Oil spills are a worldwide concern since they cause environmental problems and financial losses. Automatic detection plays a crucial role in rapid decision-making to reduce damage. In this context, deep learning and remote sensing are powerful tools with successful applications in many regions. However, there are still no studies on deep-water zones and in the Brazilian territory. The present research has three contributions: (1) create an oil spill dataset on the Brazilian region, (2) compare state-of-the-art deep learning models for this task, and (3) propose a novel application on the Campos Basin (Brazil's largest producer) using Sentinel-1 time series to identify more susceptible regions, encompassing 138 images from 2016 to 2021. The experts manually labeled the dataset with confirmation from the oil company and federal inspection, resulting in 800 images with 512 × 512 spatial dimensions and their respective annotations (600 for training, 125 for validation, and 75 for testing). The study compared three semantic segmentation architectures (U-net, DeepLabv3+, and LinkNet) with four backbones (ResNet-101, ResNet-50, Efficient-net-B0, and Efficient-net-B3) resulting in 12 models. The U-net with the Efficient-net-B3 backbone presented slightly better results (98% accuracy, 75% precision, 78% recall, 76% F-score, and 62% IoU). The time-series analysis considered images with 8,192 × 11,264 spatial dimensions. The entire image classification used a sliding window approach with a 128-pixel stride (averaging the overlapping pixels). Moreover, recurrence analysis detected the more susceptible areas and eliminated the look-alike. False-positive features have a high spatial presence, but with low recurrence (rarely reaching 3 events), which facilitates their elimination using a threshold recurrence. This novel analysis for oil spills is suitable for understanding the patterns along the time and providing regions for the authorities in real-time.

Three new species of Microlaimus are described from the continental shelf of the Campos Basin, southwest Atlantic, Brazil. Microlaimus campiensis sp. n. differs from all other species in the presence of two anterior testes, slender spicules with enlarged proximal ends, 7–11 pre-cloacal papilliform supplements, and females with a pair of constriction structures, one on each branch of the ovary. Microlaimus alexandri sp. n. shows sexual dimorphism in the size of the amphidial fovea, which occupies 100% of the diameter of the corresponding area in the male; the buccal cavity provided with five teeth and a slightly cuticularized cuticular ring. Microlaimus vitorius sp. n. has four longitudinal-lateral rows of glands associated with small pores, one seta and three pores small pre-cloacal, and the gubernaculum has a triangular base. An amendment to the diagnosis of the genus is proposed, where the number of teeth was modified.

The rift phase of the Campos Basin developed during the Early Cretaceous on a heterogeneous crust comprising structures inherited from the Brasiliano‐Pan African tectonic events, mostly generated during the Neoproterozoic‐Cambrian amalgamation of western Gondwana blocks. The main rifting episode took place from the Hauterivian to the Barremian, then was succeeded by the transition and post‐rift (SAG) phases during the Aptian. Rift faults developed as a result of a progressive rotation of extension from E‐W to NW‐SE. The role of pre‐existing intra‐basement structures on the style and evolution of the rift faults was investigated using 3D high‐resolution seismic data, borehole logs and sidewall samples. Three seismic facies (SF1, SF2 and SF3) and three types of intra‐basement structures (Surfaces, Geobodies and Internal Reflections) were identified and mapped. They represent, respectively, contrasting levels of seismic anisotropy, interpreted as metamorphic foliation, and ductile shear zones that bound rock units with particular seismic facies signatures. Sidewall cores show that banded biotite‐gneiss is the predominant rock type in the eastern half of the study area, while more homogeneous granitoid is the dominant lithology on the west. Such a binary division of lithotypes is consistent with the distribution of mapped intra‐basement seismic facies and features. The contrasting basement heterogeneity across the study area is the major control in the strain distribution during rifting. Where the basement is highly heterogeneous, the pre‐existing fabric was selectively reactivated whenever its orientation was favourable, resulting in faults forming progressively as the extension direction rotates, whilst shallower low to very low angle basement fabric were cross‐cut by rift faults. Where the basement is homogeneous, only early formed faults remain active throughout the rifting. [ABSTRACT FROM AUTHOR]

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The Electrical Submersible Pumping (ESP) system is one of the most commonly used artificial lift methods in the petroleum industry and one recent breakthrough in this system is enclosed in a capsule and positioned on the seabed in a skid. As it is a recent technology, with only a small amount of equipment currently in operation, there is a clear need for a greater understanding of the flow within this geometry with the objective of perfecting the design of this promising submarine boosting system. This paper presents a numerical investigation of single-phase flow within the scaled capsule-intake of an ESP system in the Skid considering a model with geometric and dynamic similarities in relation to a real equipment in operation in the Espadarte field, located in the Campos Basin, Brazil. The tridimensional and transient simulation for a case for one mass flow rate and inclination angles are investigated. While neglecting the effects of the diffuser and impeller in the system, the flow field features, axial and radial velocity profiles in the intake region were computed. The numerical results show that the flow in the intake region is dominated by the secondary flow, leading to the formation of bathtub vortex. It is expected that the vortices influence the flow pattern in the intake region, breaking the larger bubbles into smaller bubbles, making the transition from the slug flow pattern to the dispersed bubbles or bubbly pattern in which it would be more difficult to be dragged into the intake. [ABSTRACT FROM AUTHOR]

Cumaceans are an important component of the macrobenthic fauna and are preyed upon by several species of fishes. In the family Bodotriidae, Cyclaspis Sars, 1865 is the most speciose genus with more than 140 described species. Based on material from the Campos Basin and Espírito Santo Basin, southwestern Atlantic, we describe three new species of Cyclaspis: Cyclaspis goytacazes sp. nov., Cyclaspis lilianae sp. nov. and Cyclaspis tesauna sp. nov. We also report C. antipai Petrescu, 1995, C. roccatagliatai Petrescu, 1995 and C. unicornis Calman, 1907 as new records from the Brazilian coast. The first two species were known previously from Uruguay, and C. unicornis from the Caribbean Sea. Of the six species, only C. lilianae sp. nov. was found on the continental slope (415–1320 m) and the other five species were restricted to the continental shelf (18–139 m). A pictorial identification key for the 17 species of Cyclaspis known to occur in Brazil is provided. [ABSTRACT FROM AUTHOR]

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Abstract Given the growth the oil industry faced in contemporary Brazil and, since the Environmental Education is a compensatory measure in the federal environmental licensing, the aims of the present article are: i) mapping the publications on "environmental vulnerability"; ii) checking on the incorporation of such concept into the institutional and legal environmental education (EE) framework in oil licensing iii) understanding how the mentioned concept is used by economic agents in Macaé city. The methodology consisted of a participant observation approach used during the implementation of an EA program in Macae between 2012 and 2014, as well as of literature review, data collection in the legislation on EA in oil licensing and in technical documents produced by economic agents. Despite the advancement of academic discussions about the "environmental vulnerability" concept, we see the absence of clear criteria to define the social groups in vulnerability situations in educational activities concerning the environmental licensing.

Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are membrane lipids produced by bacteria usually ascribed to soil and peat deposits. The presence of brGDGTs in marine sediments can thus be used to track terrigenous organic matter inputs to the continental margin and to infer the local continental mean annual air temperature (MAT) and soil pH. The proxy rationale is based on the degree methylation and cyclization of the brGDGTs from terrestrial bacteria, but recently evidence was found of river and oceanic production of brGDGTs with similar configuration, indicating the necessity to better constrain the applicability of the soil brGDGTs in the marine realm. Here we considered crenarchaeol and brGDGTs obtained in 46 core-top sediments from cross-margin transects in the Campos Basin in the Southwest Atlantic, with the goal to evaluate the effectiveness of the brGDGT-associated proxies in a region in the southeastern tropical Brazilian continental margin influenced by upwelling events and low terrigenous inputs. The separation of the 5- and 6-methyl brGDGTs proved to be essential for a better evaluation of the sources of brGDGTs in the environment. Direct evidence of input of terrigenous organic matter by the medium-sized Paraíba do Sul River and other small rivers in the region were observed. More importantly, the high proportions of ring-containing brGDGTs—and the consequent increased values of the #ringstetra–in the sediments deposited between 75 and 400 m water depths (mid-shelf to upper slope) were clear evidence of marine in situ production of brGDGTs. In some stations deeper than 1,900 m, an increase in the acyclic 6-methyl hexamethylated compounds can also be ascribed to in situ production. Our results revealed that the initial soil signal is lost during transport and after river discharge in the Campos Basin, which compromise the use of brGDGTs to reconstruct the soil pH and MAT of the nearby land area.

Discovering and exploring oil in the pre-salt layer reservoirs displaced investments from the Campos Basin to the Santos Basin, causing changes in the labor market in the oil-producing regions. Hence, the present study seeks to analyze the impact of the oil sector on the labor market in places where Exploration and Production (E&P) activities are carried out, by means of the analysis of an equal number of municipalities bordering both basins, from the 2000s to the present. Information related to resident population, jobs, and educational level was considered. According to this study, municipalities that house equipment from this industry are those that provide the best indices in terms of jobs and educational level. In conclusion, the study stresses that structural changes in oil geopolitics make estimates of the evolution of the sector a very uncertain topic; however, analyses of future scenarios are still necessary. [ABSTRACT FROM AUTHOR]

Increasing continental suspended sediment influx to coral reefs is an example of land-sea coupling that requires the identification of sources, magnitude of transport, and controlling processes. In Brazil, a small coastal basin (Macaé River) was identified as a source of suspended sediment to a coral reef on the coast of Cape Armação dos Búzios. Biannual suspended sediment loads were measured at the basin as were fluxes within the estuary and towards the coast during eight tidal cycles. Particle load and yield from this basin were typical of small coastal basins, showing high to moderate slopes and transitional land management. However, the magnitude of the river loads was lower than the sediment transport within the estuary, indicating that the estuary amplifies river fluxes and sustains the transference of suspended sediment alongshore to the coral reef. Nonetheless, the estuary displays both suspended particle retention and export capacity and, therefore, fluxes to the coast and the coral reef occur as episodic events. [ABSTRACT FROM AUTHOR]

The compressional and shear-wave velocities ( V P and V S ) have been used in studies for hydrocarbon exploration over the last decades. Nevertheless, the absence of S-wave velocity records in geophysical surveys is common. In this work, we applied the iterative method proposed by Lee (2006), which allows evaluations of P- and S-wave velocities by estimates of the consolidation parameter α. We use well-log datasets from a turbiditic reservoir at Namorado Oilfield (Campos Basin, southeastern Brazil) to test this methodology. Results were further compared to a well-established empirical model (Greenberg and Castagna, 1992). We verified a good agreement for V S results provided by both methods, and a consistent correspondence between the measured V P and those calculated by the Lee (2006) method. It was also possible to assume the reliability of the α values, although the presence of denser lithologies may produce local artifacts, which affect V P (α) and V S (α) estimates. Furthermore, the results for α , V P (α) and V S (α) pointed to: (i) an upward trending for V P V S ratio values, for profile NA-01, that indicate a possible hydrocarbon-filling zone; (ii) the presence of two distinctive α data groupings with respect to porosity, which are clearly influenced by the involved type of lithologies; and (iii) the absence of a straightforward relationship between α and porosity under pressure conditions. • Evaluation of prediction models for sonic velocities and consolidation parameters. • Compatibility between measured and estimated velocities along the stratigraphy. • Identification of artifacts at estimated velocity values due to denser lithologies. • Trending for VP/VS ratio values indicating possible hydrocarbon-filling zone. • Absence of direct relationship between α and porosity under pressure conditions. [ABSTRACT FROM AUTHOR]

Investigation were carried out targeting distribution and source apportioning of hydrocarbons in surface sediments from shallow to deep waters in the Campos Basin, one of the most important oil-producing provinces in Brazil. The observed levels of aliphatic (≤ 124 μg g−1) and polycyclic aromatic hydrocarbons (PAHs ≤ 599 ng g−1) are lower than those considered relevant for environmental risk to the benthic habitats. Higher median concentrations of aliphatic hydrocarbons (8.49 μg g−1) and PAHs (84.8 ng g−1) in the middle slope sediments (700–1000-m water depths) showed the influence of hydrodynamics upon hydrocarbon accumulation in the sediments. Diagnostic ratios and conventional statistical analysis applied to hydrocarbon data produced insufficient information on the contribution of different sources. These traditional approaches do not consider the potential changes affecting source assignment and therefore cannot deal with the uncertainties. The fuzzy logic applied as an alternative method for data treatment successfully incorporated the uncertainties in the differentiation between petrogenic and pyrolytic sources, including those due to degradation. Moreover, by using fuzzy logic, it was possible to identify that water circulation patterns, mass transport, deposition, and degradation processes are more relevant factors in determining hydrocarbon composition than source proximity. [ABSTRACT FROM AUTHOR]

Many marine organisms spend the early life history stages in neuston domain. Although the importance of ichthyoneuston, few studies were developed in the Southwest Atlantic Ocean. Therefore, this study aimed to improve the knowledge on ichthyoneuston of the Brazilian coast analyzing the vertical stratification and horizontal distribution of these organisms. Neuston samples were collected in daylight between 20°S and 23°S from February to April 2009 (late summer/early autumn; rainy season) and from August to September 2009 (late winter/early spring; dry season). Eggs of six taxa were identified: Anguilliformes, Engraulidae, Clupeidae, Synodontidae, Trichiuridae, and Maurolicus stehmanni (Sternoptychidae). The neustonic larval fish assemblage was composed by 40 families and 63 species. Mullidae and Myctophidae larvae were the most abundant in the rainy period while Mullidae and Mugilidae dominated in the dry season. Seasonal and spatial variation of larval fish assemblages in the neuston were structured by oceanographic features. The larval fish abundance on the outer slope stations may have been favored by the advection of an anticyclone that encompassed most of the study region during the cruise periods. In the rainy season, salinity and local depth structured the larval fish assemblage in a cross‐shelf gradient, while in the dry season the larval assemblage was structured around temperature and north‐south gradient. In the dry season, the cross‐shelf gradient was less pronounced mainly because of the low abundance and frequency of mesopelagic larvae. The low frequency and abundance of some species are probably related to the net avoidance of fish larvae during the day or dial vertical migration, as many species migrate to deeper layers during the day and ascend to neuston only at night. Nevertheless, the present study presented baseline information about the seasonal and spatial variation of the neustonic larval fish assemblage influenced by the oceanographic conditions in the Campos Basin. We recommend to additionally collect night samples to decrease larval escapement rates and to compare night versus day catches to further investigate the influence of daily migration in the neustonic larval fish in the area. [ABSTRACT FROM AUTHOR]

Abstract Unplanned oil spills during offshore oil production are a serious problem for the industry and the marine environment. Here we assess the biodegradation potential of marine microorganisms from three water depths in the Campos Basin (South Atlantic Ocean): (i) 5 m (surface), (ii) ∼80 m (chlorophyll maximum layer), and (iii) ∼1200 m (near the bottom). After incubating seawater samples with or without crude oil for 52 days, we used metagenomics and classic microbiology techniques to analyze microbial abundance and diversity, and measured physical-chemical parameters to better understand biodegradation processes. We observed increased microbial abundance and concomitant decreases in dissolved oxygen and hydrocarbon concentrations, indicating oil biodegradation in the three water depths treatments within approximately 27 days. An increase in metagenomic sequences of oil-degrading archaea, fungi, and bacteria (Alcanivorax , Alteromonas , Colwellia, Marinobacter , and Pseudomonas) accompanied by a significant increase in metagenomic sequences involved in the degradation of aromatic compounds indicate that crude oil promotes the growth of microorganisms with oil degradation potential. The abundance of genes involved in biodegrading benzene, toluene, ethylbenzene, xylene, alkanes, and poly-aromatic hydrocarbons peaked approximately 3 days after oil addition. All 12 novel metagenome-assembled genomes contained genes involved in hydrocarbon degradation, indicating the oil-degrading potential of planktonic microbes in the Campos Basin. Image 1 • Oil biodegradation may vary throughout the ocean water column. • Oil degrading microorganisms increase after oil addition to seawater. • Gene sequences involved in petroleum degradation increase consequently. • 12 novel microbial lineages (MAGs) have the potential of oil biodegradation. "Oil biodegradation occurs throughout the ocean water column with similar biodegradation rates occurring in the surface and deep (∼1200 m) oceanic waters." [ABSTRACT FROM AUTHOR]

Highlights • Mg-clay deposits constitute the background of the sag lacustrine sedimentation. • Calcite crusts are syngenetic precipitates formed directly on Mg-clay laminations. • The silicification process occurred relatively quickly after dolomitization. • Fault systems have concentrated the dissolution and precipitation of minerals by fluid flow. • Hydrothermal alteration has an impact on permeability, fluid flow, and dynamic behavior. [ABSTRACT FROM AUTHOR]

Abstract Igneous intrusions are important for the exploration and appraisal phases of an oilfield due to their impact on petroleum systems. Their presence can be associated with the generation, migration, accumulation, and entrapment of hydrocarbons. In particular, (1) sills with low permeability might form barriers to fluid flow and migration; (2) sills may re-use fracture networks, providing insights on fluid migration and interaction(s); (3) sills may influence source rock maturation, (4) sill-induced uplifting of overburden and faulting may generate traps, and (5) their geometric complexities enables the understanding of the interconnectedness of sill complexes, which is the focus of this study. Therefore, we provide a systematic characterization of sill geometries and their morphometric parameters. We used three-dimensional seismic data, calibrated with well logs, to interpret sills in the southern Campos Basin, Brazil. Throughout the Late Cretaceous until the Paleogene, sills intruded into the Cretaceous to the Eocene post-salt sedimentary sequence, including shallow-platform carbonates, transgressive marls, and shales. A morphometric analysis assisted by seismic attributes allowed the geometric characterization of sills, namely: (1) saucer-shaped; (2) slightly saucer-shaped; (3) climbing saucer-shaped; (4) transgressive; and (5) rough layer-parallel. The documented sills comprise a wide range of sizes (0.43–14.35 km2) that increase with depth (up to 3.18 km), extend vertically from 0.06 to 0.23 km, and vary from low (1.82–3.31°) to high dip (6.05–15.74°). The sill complex area extends over 67.35 km2. This study suggests that a thorough characterization of sill intrusions may have a substantial influence on the prediction of other igneous occurrences. The mapped sills might have implications not just on the acoustically similar shallow platform Albian carbonates of the Macaé Group, but may also provide insightful geometric constraints on the Brazilian pre-salt igneous intrusions. Highlights • Igneous rocks show typical subsurface borehole characteristics in SE Brazil. • Morphometric analyses allow the geometric characterization of magmatic sills. • Multi-attribute analyses are powerful tools to identify magmatic sills. • RGB color blending from spectral decomposition is key in quantitative analyses of sills. • A tuning frequency of approximately 20 to 45 Hz characterizes the interpreted sills. [ABSTRACT FROM AUTHOR]

Abstract The Eastern Marlim oilfield, located in the northeastern offshore of the Campos Basin, is a portion of the Marlim Complex, one of the most important oil accumulations ever found in Brazil. This paper presents findings from lithofacies, sequence stratigraphy and petrophysical analyses for the Oligocene-Miocene section of the Eastern Marlim oilfield. Here, we evaluate at least four main lithofacies associations and three major zones recognized in the latter section, presenting sedimentological and stratigraphical interpretations based on stratigraphic correlations, distribution and sand proportion maps, and accompanying petrophysical analysis. Our findings suggest at least two bipartite turbiditic flows representing different stages of deposition associated with a deep-water turbidite sequence, composing the elements of a submarine lobe complex. Massive unconsolidated amalgamated sandstone bodies, displaying very good porosity, lateral and vertical continuity, reflecting excellent reservoirs. The final depositional model of the studied Oligocene-Miocene interval in this work is part of the first-order Highstand System Tract (HST) of the Campos Basin, which in turn represents a second-order, exploration-scale depositional sequence. Finally, the sequence stratigraphic model of the Oligocene-Miocene section of the Eastern Marlim oilfield has an architecture similar to those that have been developed from Oligocene-Miocene global sea level changes. Highlights • A lithofacies, sequence stratigraphic and petrophysical evaluation is proposed for the Eastern Marlim oilfield. • Four main lithofacies and three major zones were recognized. • Two-bipartite turbiditic flows represent different stages of deposition. • A deep-water submarine lobe complex was identified. • The studied section represent a first order HST and a second order depositional sequence. [ABSTRACT FROM AUTHOR]

The purpose of this article is to discuss the audiovisual production as an activity to identify the “environmental impacts”, in environmental education in the context of petrol and gas Brazilian licensing process. The question is: Can collective film production be an instrument to express the notion of “environmental impact” of which the social groups belong to? Such a question is answered by reading the documentaries aimed at strengthening local social struggles. Thirty documentaries produced in 2007 were analyzed in ten counties located on the coast of Rio de Janeiro. It shows that the aesthetic form of the documentaries, the search for the look of “affected” and, above all, the direction of the camera reveal nuances of how the groups understand the “environmental impacts” of the economic development process, contributing to further discussions regarding the local implementation of environmental policy, for example, democratic and participatory territorial management. The study concludes pointing out that the production of documentaries as social participation instrument in this case seem to have punctual and temporary effects.

This paper presents morphological descriptions and ecological data of cryptogam spores and other non-pollen palynomorphs from Quaternary sediments of Campos Basin, Rio de Janeiro, SE Brazil. The ages were derived from biostratigraphy of planktonic foraminifers and two radiocarbon dates, and suggest that sediment deposition started in the last 140,000 years BP. Thirty different types of palynomorphs were identified, described, and photographed: two bryophyte spores (sensu lato); 21 pteridophyte spores; four freshwater microalgae; onePseudoschizaea; and two microfungi. Some of the identified spores (Sphagnum, Blechnum, Cyatheaceae, Dennstaedtiaceae, Lycopodiella, Microgramma, Polypodium, Acrostichum, Pityrogramma, and Lygodium) are related to the modern flora found on the northern coast of Rio de Janeiro State, at the Restinga of Jurubatiba, from vegetation types such as shrub swamp/coastal swamp formation, seasonally flooded forest, Clusia and Ericaceae woods, and disturbed vegetation. The freshwater microalgae and the microfungi are also presently recorded from the coastal lagoons of this region. The high spore concentration in slope sediments reflects the intense terrigenous influx, caused by a relative low sealevel during glacial stages. Palynological analysis suggests the presence of taxa from flooded forests and humid areas in the coastal plain during glacial and interglacial stages of the Late Pleistocene.

Abstract The formation of rifted margins involves the deformation of pre-existing lithosphere whose rheological and mechanical behavior during extension is complex since it is the product of numerous earlier tectonic events. In this work we investigate the Campos Rifted Margin (CRM) architecture, with the aim of exploring the role of basement inheritance and early magmatism on margin evolution. We present a new compilation of high resolution aeromagnetic data, integrated with seismic interpretation and crustal thickness from 3D gravity inversion, to resolve margin architecture, ocean-continent transition (OCT) structure and the oceanward extent of continental basement. We examine the lateral variation of crustal rheology, necking geometry and rift segmentation, revealing striking spatial heterogeneities that separate three distinct sectors along the Campos margin. The basement of the Campos Rifted Margin consists of Precambrian/Eo-Paleozoic Ribeira Belt (RB) and the easternmost Cabo Frio Tectonic Domain (CFTD) whose Neoproterozoic-Cambrian nappes and thrusts are well preserved offshore and give a rheologically layered crust. This pre-rift basement configuration, along with the Mesozoic magmatism, has resulted in different crustal responses to extension which vary from north to south. It influenced the temporal and spatial distribution of deformation, and as a consequence, the necking geometry, subsidence and sedimentary evolution of the margin. We show that the Campos basin evolution was controlled by crustal inheritance corresponding to that observed in onshore basement terranes. The more massive basement of the northern Campos basin can be correlated with the post-collisional Cambro-Ordovician magmatic province of the Aracuai belt that partially obliterated the earlier orogenic structures. The lack of a structured crust localized the strain generating the observed narrow necking zone. In addition, its more mafic composition resulted in a competent crust which also influenced the rifting processes. In contrast the basement of the central and southern Campos margin, represented by the Cabo Frio Tectonic Domain, is structurally and petrologically distinct from the Aracuaí Belt and has layered orogenic crust which responded differently to rifting stresses forming the observed wide necking zone. We propose that the Campos Rifted Margin evolved from a pre-rift complex inherited rheology which dominated the first stages of rifting. However once the crust was highly extended, the deformation was nearly synchronous regionally, leading to giant salt basin formation and breakup. Highlights • Campos margin shows clear variations in ocean-continent structure from north to south. • Crustal rheology and magmatism controlled extensional mode. • The thinning geometry is a first-order parameter in defining the margin architecture. [ABSTRACT FROM AUTHOR]

The larval shells of Antalis circumcincta (Watson, 1879) (order Dentaliida), Pertusiconcha callithrix (Dall, 1889) (order Gadilida) and of an undetermined species of uncertain systematic position are described. The material studied comprises mainly samples from deep waters, collected by expeditions along the southeast coast of Brazil. The larval shell of the three taxa matches other types previously described in the literature. Antalis circumcincta and P. callithrix have four regions (protoconch A, protoconch B, teleoconch A, teleoconch B), but differ in dimensions and sculpture from each other, while the undetermined species has three regions (protoconch A, protoconch B, teleoconch B). A morphometric approach combined with a discriminant analysis also indicates that the three taxa are significantly distinct. This study confirms patterns of larval shells at the taxonomic rank of orders but other supraspecific patterns remain uncertain. [ABSTRACT FROM AUTHOR]

Copyright of Anuario do Instituto de Geociencias is the property of Universidade Federal do Rio de Janeiro, Instituto de Geociencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Highlights • The applicability of U 37 K ' and T E X 86 H proxies was investigated in the Campos Basin. • In general, reconstructed and measured temperatures correlate well for both proxies. • Coastal upwelling locally affects the proxies. • No effect of terrestrial input on T E X 86 H values was found. • U 37 K ' and T E X 86 H can be used for paleoclimate studies in the SE Brazilian margin. Abstract The applicability of two organic geochemical proxies (U 37 K ' based on alkenones and T E X 86 H based on glycerol dialkyl glycerol tetraethers) for ocean temperatures was investigated on a regional scale in the SE Brazilian continental margin (Campos Basin) using 53 core-top sediments. In 71% of the samples for U 37 K ' and 85% for T E X 86 H , the estimated annual mean sea surface temperature (SST) is comparable to the climatological annual mean data, with deviations within the calibration error. The surface T E X 86 H estimates reflects the surface mixed layer, while the depth-integrated (0–200 m) T E X 86 H estimates showed better agreement with temperatures at 100–200 m depth. In addition, the SST- U 37 K ' results were more consistent (73% of the samples) using a winter calibration rather than an annual mean calibration. This seasonal effect might be ascribed to an increase in the abundance of haptophytes in the region during the winter. Exceptions to these general trends were observed for both proxies as a strong cold bias in reconstructed temperature in a few samples in the southern portion of the studied region, which may be related to (i) a predominant subsurface habitat of Thaumarchaeota combined with enhanced primary production and flux of particles during upwelling and (ii) alkenones being laterally transported from adjacent colder waters. Effects of river input of terrestrially sourced GDGTs on T E X 86 H are not evident. Overall, our findings show that U 37 K ' and T E X 86 H are suitable temperature proxies for paleoclimate studies at a regional scale in the SE Brazilian continental margin, but on a local scale the effects of upwelling must be taken in consideration. [ABSTRACT FROM AUTHOR]

Abstract Lacustrine carbonatic deposits are generally little studied, partly because of their lesser representativity in the global geological record, as well as the smaller amount of oil reservoirs associated with these types of rock. But the Cretaceous (Aptian \ Barremian) lacustrine carbonates recorded on the eastern Brazilian coast from Santos to Sergipe-Alagoas basins, attributed to the rift and post-rift phases that preceded the opening of the Atlantic Ocean, has been registering important hydrocarbon discoveries since the 1970s to the present day. This study aimed to expand the knowledge of these deposits by analysing the facies and associations, defining sequences according to the current understanding of the sequence stratigraphy concepts. Rock samples were described associated with core and seismic profile data from the Badejo, Linguado, Pampo and Trilha fields in the Campos Basin. As the main lithology sampled was bioclastic (bivalves) carbonates. Were defined fifteen facies according to sedimentological criteria associated to taphonomy concepts and also grouped in four associations interpreted according to the hydrodynamic gradient of a wave-dominated shelf. This enabled the definition of high and medium frequency sequences, which aided the description of three internal sequences in the interval known as Lower Coquina. This methodology can be used to interpret facies spatial distribution and serves as an analogue for cycles definition in similar depositional systems. Highlights • Cretaceous lacustrine carbonates facies characterization. • Definition of high frequency cycles and stratigraphic correlation in carbonates. • Proposition of a model to support pre-salt "coquinas" reservoir development. [ABSTRACT FROM AUTHOR]

Abstract The current research was performed in the eastern portion of the Marlim oilfield to identify the hydrocarbon-generating potential of the Albian-Oligocene sequences (Macaé Group, Ubatuba and Carapebus formations) in the Campos Basin, Brazil. On the basis of petroleum geochemical proxies, an integrated approach was developed using source rock characterizations to establish the distribution of source rock properties, such as organic matter content, hydrocarbon-generating potential, thermal maturity and stratigraphic thickness. The outcomes of a comprehensive petroleum geochemical characterization were integrated with cuttings and core sample descriptions, biostratigraphic controls, well log analyses and 2-D/3-D seismic interpretations. Our results reveal that for the Albian-Oligocene deposits, the key geochemical properties required to develop hydrocarbon source kitchens converge in specific locations, demonstrating a variable hydrocarbon potential ranging from poor to excellent and suggesting the existence of local generation pods in the central and principally northern portions of the research area. The accumulation and preservation of the organic matter were influenced by the paleo-topography and tectonic controls, and the lowest concentrations of organic carbon were attributed to significant siliciclastic dilution taking place mostly toward the middle and southern portions of the Eastern Marlim oilfield. Lateral variations in both the lithofacies and organic facies are the main conditions controlling the behavior of the petroleum potential in the investigated sediments. Our results indicate that the Macaé Group has sufficient source-rock potential, maturation patterns, and hydrocarbon-generating potential to be considered as an active source rock in the Eastern Marlim oilfield, where the petroleum geochemical properties converge and are adequate to generate hydrocarbon compounds. In addition, the Ubatuba and Carapebus formations are also likely to generate oil and/or gas, but due to their relatively low maturity, it is difficult to establish that these rocks can be active source rocks in the study area. Graphical abstract Image 1 Highlights • A petroleum geochemical characterization is proposed in the Eastern Marlim oilfield. • Local generation pods were recognized in the northern portion of the study area. • Significant siliciclastic dilution takes place mostly toward the south of the field. • Paleotopography and tectonic controls influenced the behavior of the organic matter. • The Macaé Group may have significant hydrocarbon generation potential. [ABSTRACT FROM AUTHOR]

This paper introduces a new method for history matching, combining the Iterative Discrete Latin Hypercube (IDLHC) with multi-start Simulated Annealing methods. The proposed method, named IDLHCSA, combines the potential of the IDLHC in finding good matched models while preserving the diversity of solutions and the potential of the SA with local control in finding local (refined) solutions. The IDLHCSA was applied in two cases. The first is a simple reservoir model used as proof of concept. The second is a complex benchmark case (UNISIM-I-H) based on the Namorado field, located at the Campos Basin, Brazil. The robustness and effectiveness of the proposed method are demonstrated by comparison with other consolidated methods. It is demonstrated here that, when compared to other methodologies, the proposed method is more effective in finding multiple solutions for the history matching problem while maintaining solution diversity. The production forecast is analyzed and the predictive capacity of the matched models is assessed. The paper reveals that obtaining good matched models does not ensure reliable forecasts. The proposed method was able to find matched models which provided more reliable forecasts when compared to other methods. [ABSTRACT FROM AUTHOR]

Three‐dimensional seismic data from an oilfield in the Campos Basin, SE Brazil, was used to characterize a karstified unconformity surface at the top of the Albian – Cenomanian Macaé Group. Macaé Group carbonates underwent intense karstification associated with subaerial exposure during a period of some 10 to 15 Ma resulting in the development of canyons, valleys, sinkholes and cave systems. The carbonates host commercial oil accumulations at a number of important oil fields. Understanding how the karstification process has affected the carbonates' reservoir properties is essential for future exploration, not only to improve recovery rates but also to avoid drilling‐related issues such as thief zones. In this context, this study aims to characterize the top‐Macaé Group paleokarst system by investigating the morphology of the associated reflectors recorded on seismic data, together with endokarst features in the underlying carbonate succession such as cave systems and collapse structures. The top‐Macaé Group seismic horizon can be divided into two principal geomorphological domains: highlands, characterized by abrupt relief with well‐developed erosional features; and lowlands, marked by a smoother topography. Collapse sinkholes occur in both domains and take the form of closed circular depressions. The study of endokarst features from an analysis of amplitude anomalies (bright spots) indicates the presence of heterogeneous cave systems. The interpreted data contributes to a better understanding of the spatial distribution of the paleokarst system in the Macaé Group carbonates and may assist with future hydrocarbon exploration in the Campos Basin. [ABSTRACT FROM AUTHOR]