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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.

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]

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 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]

Copyright of Revista Ambiente e Água is the property of Revista Ambiente e Agua 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.)

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]

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]

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]

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.

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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]

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.)

A new amphipod species of Metharpinia Schellenberg, 1931 is described from Campos Basin, southeastern Brazilian coast. The material was collected with van Veen grab from unconsolidated substratum, off the mouth of the Paraíba do Sul River. The new species can be distinguished from its congeners by presenting a strongly constricted rostrum and a slender palp of maxilla 1. There are four species in Metharpinia from the South Atlantic: M. dentiurosoma Alonso de Pina, 2003, M. grandirama Alonso de Pina, 2003 and M. iado Alonso de Pina, 2003, and Metharpinia taylorae sp. nov. This is the first record of a species of the genus from Brazilian waters.

This paper is concerned with the reliability of two different models to compute acoustic impedances in the Namorado oilfield, Campos Basin, Brazil. The acoustic impedance is a physical property related to the interaction of a seismic pulse and the components of the rock. This interaction is useful to understand lithological aspects of the studied area. Numerous models have been proposed in the literature with undesirable results. Particularly for Namorado oilfield, there is few models to estimate acoustic impedances in a reliable framework, specially for lack of log data. To achieve this purpose, we use a petrophysical expression that directly estimates acoustic impedances without the need of density logs. In addition, we also discuss empirical expressions to compute compressional velocities using other log data. To validate both models, we calculate the observed acoustic impedance directly from the elastic theory and also present 2-D maps of impedances for the whole Namorado oilfield. The results show that both models are good for low values of impedance, despite of the overall sub-estimation of the acoustic impedance by the petrophysical model. The empirical model presents more dispersive estimations of acoustic impedance when faced with the observed impedance. With this paper, we are intended to present more possibilities for the poor data coverage of Namorado oilfield. [ABSTRACT FROM AUTHOR]

A hydraulic flow unit (HFU) is a region in a reservoir that presents similar petrophysical and fluid flow properties. The identification of HFUs has been possible from core and well-log data based on the Kozeny-Carman's equation for permeability. Amaefule et al. were the first to propose a model to determine HFUs as those regions that present the set of flow zone indicator (FZI) points lying on a straight line of unit slope coming from a curve fitting. Recently, we conjectured that the maximum closeness centrality, a metric used in graph theory, provides suggestive points for placement of production zones within a reservoir. This was supported by a few simulations focused on assessing the oil recovery factor of rock clusters formed from the synthetic field. In this paper, we present an extension of the former study to maximum closeness centrality networks formed from two approaches: isolated setup and immersed setup. Several oil recovery and cumulative oil production simulations were performed considering these approaches both over the well-known SPE 2 model and the UNISIM-I-D model, which was built up from datasets of the Namorado Oil Field located in Campos Basin, Brazil. Four major data groups with new results were yielded, thereby revealing that our underlying conjecture is computationally feasible and very reliable to support well placement and production strategies. [ABSTRACT FROM AUTHOR]

Mercury (Hg) may originate from both anthropogenic and natural sources. The measurement of spatial and temporal variations of Hg isotope ratios in sediments may enable source identification and tracking of environmental processes. In this study we establish the distribution of mercury concentrations and mercury isotope ratios in surface sediments of three transects along the continental shelf and slope in Campos Basin-RJ-Brazil. The shelf showed on average lower total Hg concentrations (9.2 ± 5.3 ng g −1 ) than the slope (24.6 ± 8.8 ng g −1 ). MMHg average concentrations of shelf 0.15 ± 0.12 ng g −1 and slope 0.13 ± 0.06 ng g −1 were not significantly different. Distinct differences in Hg isotope ratio signatures were observed, suggesting that the two regions were impacted by different sources of Hg. The shelf showed more negative δ 202 Hg and Δ 199 Hg values ranging from −0.59 to −2.19‰ and from −0.76 to 0.08‰, respectively. In contrast, the slope exhibited δ 202 Hg values from −0.29 to −1.82‰ and Δ 199 Hg values from −0.23 to 0.09‰. Mercury found on the shelf, especially along the “D” and “I” transects, is depleted in heavy isotopes resulting in more negative δ 202 Hg compared to the slope. Isotope ratios observed in the “D” and “I” shelf region are similar to Hg ratios commonly associated with plants and vegetation and very comparable to those detected in the estuary and adjoining mangrove forest, which suggests that Hg exported from rivers may be the dominating source of Hg in near coastal regions along the northern part of the shelf. [ABSTRACT FROM AUTHOR]

Here, we describe pollen grains extracted from a Pleistocene-Holocene sediment core (BU-91-GL-05; 22°48'45"S; 41°54'13"W) taken from the Albacora Slope (22°48'45"S; 41°54'13"W), located in the Campos Basin of the northern region of the state of Rio de Janeiro, Brazil. The analysis resulted in the identification and morphological description of 46 types of pollen: one of a gymnosperm genus (Podocarpus); and 45 of angiosperm taxa across 27 families-one family of monocotyledons (Poaceae) and 26 families (30 types) of dicotyledons. The most common angiosperm families were Amaranthaceae (Chenopodium, Amaranthus and Gomphrena); Fabaceae (Fabaceae type, Bauhinia, Inga and Canavalia); Malpighiaceae (Tetrapteris, Heteropteris and Peixotoa); Malvaceae (Sida, Abutilon, Hibiscus and Pseudobombax); Rubiaceae (Faramea, Borreria and Psychotria); Asteraceae (Eupatorium and tribe Vernonieae); Bignoniaceae (Bignoniaceae type, Adenocalymma and Tabebuia); and Onagraceae (Fuchsia and Ludwigia). The palynoflora in this study are associated with dense montane and submontane Atlantic Forest, semideciduous forest and restinga (coastal woodland), all of which are present in the state of Rio de Janeiro. Palynological analysis can provide important data about paleovegetation and paleoclimatic changes in the studied area during the Quaternary, specifically in the last 145,000 years.

O presente trabalho apresenta uma comparação entre algumas rodadas do modelo numérico de geração e propagação de ondas Wavewatch III empregando campos de vento com diferentes resoluções espaciais e temporais em uma região tropical do oceano Atlântico Sul. Os campos de vento utilizados de entrada são os da Reanálise do NCEP (com resolução espacial de cerca de 2º e resolução temporal de 6 horas), do Global Forecast System (resolução espacial de 1º e resolução temporal de 6 horas), bem como os campos de maior resolução espacial e temporal de um modelo de mesoescala (Mesoscale Modeling System), com resolução espacial de 0,2º e resolução temporal de 1 e 6 horas. As estimativas de altura significativa, período de pico e direção principal de propagação do Wavewatch III, assim como as estimativas dos ventos usados como entrada, são comparadas com as medições de ondas de um radar e de um anemômetro, ambos instalados na Bacia de Campos, sudeste do Brasil. Os resultados mostram que campos de vento com maior resolução espacial têm um impacto positivo sobre a previsão das ondas. No entanto, mantendo a mesma resolução espacial e aumentando a resolução temporal, não se obtém melhores estimativas dos campos de onda.This work presents a comparison among several runs of the numerical wave model, Wavewatch III (WW3) employing different temporal and spatial resolutions for the wind fields in a tropical area of the Southern Atlantic Ocean. The input wind fields are from the National Centers for Environmental Prediction (NCEP) reanalysis, with 2º spatial resolution and 6 hours temporal resolution, the Global Forecast System (GFS) analysis, with 1º spatial resolution and 6 hours temporal resolution, as well as the higher spatial and temporal resolution fields of a mesoscale model (Mesoscale Modeling System), with 0.2º spatial resolution and temporal resolution of 1 and 6 hours. The WW3 estimates of significant wave height, peak period and main propagation direction, as well as the wind estimates used as input, are inter-compared against a radar wave measurements and wind speed and direction recorded from an anemometer, both instruments operating on board at an oil platform in the Campos Basin, south-eastern Brazil. The results show that a higher spatial resolution for the wind input has a positive impact on the wave estimates. However, maintaining the same spatial resolution and increasing the temporal resolution does not translate into significantly better wave estimates.

Plant components recognized as trichomes (unicellular or multicellular structures occurring in the plant epidermis) havebeen being recorded in Cretaceous sediments submitted for palynological analyses. The objective of the present paper is to record the occurrence of these fossil trichomes, and to classify them by proposing an artificial scheme that could be applied for biostratigraphic purposes. The material analyzed derives mainly from petroleum wells that penetrated Cretaceous strata in the Santos and Campos basins of offshore southeastern Brazil. Based on selected characteristics (number of arms, relative diameter, number of cells, type of base, angle formed by arms, central area pattern and presenceof stalk), twelve basic morphotypes are identifiable: (1) simple; (2) T-shaped; (3) Y-shaped; (4) double (twin); (5) triple; (6) fasciculate; (7) tufted fasciculate; (8) multiradiate; (9) tufted multiradiate; (10) three-dimensional stellate; (11) tufted three-dimensional stellate; and (12) planar (two-dimensional) stellate. Within each of these morphotypes, subtypes based on secondary characteristics (morphology of arm ends, curvature, sinuosity etc.) could be recognized, thus resulting in 63 morphotaxa. Clearly, this large morphological variability among trichomes presents significant scope for their application in biostratigraphy. This assumes especial importance in the Santonian (Upper Cretaceous) strata of the Santos and Campos basins, where paleowildfires caused by regional volcanism have resulted in the scarcity of conventional, biostratigraphicallysignificant palynomorphs (spores and pollen grains).

The genus Lepechinella Stebbing, 1908 has a cosmopolitan distribution and includes 28 species. The three new species of the genus described herein were provided from samples collected from the slope of Campos Basin, as part of the Campos Basin deep-sea environmental project. Samples were taken using a box corer between the depths of 700 and 2000 m. Lepechinella hirsuta n. sp. is characterised by the presence of simple setae on the dorsal midline of the body, an anterior tooth and an anterolateral projection on peraeonite 1; Lepechinella campensis n. sp. has peraeonite 1 dorsally sinuous and a posterior upright tooth on peraeonites 2 to 7; and Lepechinella laurensi n. sp. has peraeonites 1 to 4 dorsally sinuous and a posterior inclined tooth on peraeonites 5 to 7. This study provides full descriptions of these three new species and an identification key for South Atlantic species of the genus Lepechinella.

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Reservoir static modelling plays a fundamental role in the evaluation phase of a petroleum field. Integrated modelling allows a better understanding of how the local geology and depositional systems are related through the distribution of facies and petrophysical properties within the reservoir. In this study, geological static models of the siliciclastic Carapebus Formation of Campos Basin were built using subsurface data. The applied methodology was divided into five phases: (1) establishment of a conceptual model, (2) building of a structural model, (3) generation of 100 realizations of lithofacies using sequential indicator simulation, (4) generation of 100 realizations of porosity and permeability using sequential Gaussian simulation, and (5) validation of models by targeting both statistical and geological consistency. The obtained models are consistent and honor the conditioning data. A lithofacies constraint is crucial to better characterize the petrophysical properties distribution of the reservoir. A Dykstra-Parsons coefficient of V=0.52 characterizes this reservoir as moderately homogeneous. [ABSTRACT FROM AUTHOR]

Synthetic Aperture Radar (SAR) onboard satellites is the only source of directional wave spectra with continuous and global coverage. Millions of SAR Wave Mode (SWM) imagettes have been acquired since the launch in the early 1990's of the first European Remote Sensing Satellite ERS-1 and its successors ERS-2 and ENVISAT, which has opened up many possibilities specially for wave data assimilation purposes. The main aim of data assimilation is to improve the forecasting introducing available observations into the modeling procedures in order to minimize the differences between model estimates and measurements. However there are limitations in the retrieval of the directional spectrum from SAR images due to nonlinearities in the mapping mechanism. The Max-Planck Institut (MPI) scheme, the first proposed and most widely used algorithm to retrieve directional wave spectra from SAR images, is employed to compare significant wave heights retrieved from ERS-1 SAR against buoy measurements and against the WAM wave model. It is shown that for periods shorter than 12 seconds the WAM model performs better than the MPI, despite the fact that the model is used as first guess to the MPI method, that is the retrieval is deteriorating the first guess. For periods longer than 12 seconds, the part of the spectrum that is directly measured by SAR, the performance of the MPI scheme is at least as good as the WAM model.

A new amphipod species of Metharpinia Schellenberg, 1931 is described from Campos Basin, southeastern Brazilian coast. The material was collected with van Veen grab from unconsolidated substratum, off the mouth of the Paraíba do Sul River. The new species can be distinguished from its congeners by presenting a strongly constricted rostrum and a slender palp of maxilla 1. There are four species in Metharpinia from the South Atlantic: M. dentiurosoma Alonso de Pina, 2003, M. grandirama Alonso de Pina, 2003 and M. iado Alonso de Pina, 2003, and Metharpinia taylorae sp. nov. This is the first record of a species of the genus from Brazilian waters. [ABSTRACT FROM AUTHOR]

A systematic study of 71 samples of sandstones and conglomerates of the Itabapoana Formation (Aptian), selected from the cores of 13 wells in the offshore portion of Campos Basin, eastern Brazil, allowed the recognition of the main primary and diagenetic constituents and pore types, and their space and time relations. These rocks are contemporaneous to the extensive, lacustrine “Pre-Salt” carbonate reservoirs under exploration. The rocks range from very fine-grained sandstones to conglomerates, with predominance of very coarse-grained sandstones, and their original detrital composition corresponds to lithic arkoses and feldspathic litharenites, rich in volcanic rock fragments (VFRs). Smectitic clay minerals are the most abundant diagenetic constituents, related mostly to the alteration of VRF, heavy minerals and biotite. Burial and thermal history and fluid flow also played a fundamental role on the diagenetic processes and reservoir quality. The main diagenetic processes were the dissolution of volcanic fragments, feldspars and heavy minerals, the authigenesis of smectites, hematite, dolomite, calcite, zeolites and titanium oxides in intergranular pores and replacing VRFs, feldspars, biotite and heavy minerals, mechanical and chemical compaction, and the albitization of feldspars, mostly of plagioclase. Primary intergranular porosity was strongly reduced by compaction, and by smectite, calcite, dolomite and zeolite cementation. On the other hand, secondary porosity was generated by the dissolution of primary and diagenetic constituents, as well as by fracturing. The understanding of the space and time distribution of diagenetic processes in these rocks will allow the development of predictive models of their quality, which may contribute to the reduction of risks involved in their exploration. [ABSTRACT FROM AUTHOR]

The distribution, size structure, and feeding of three sea robin species belonging to the family Triglidae (Bellator brachychir, Prionotus nudigula and Prionotus punctatus) were studied based on specimens caught with bottom trawls on the continental shelf of Campos Basin, southeastern Brazil. The two Prionotus species were more concentrated in the inner shelf (<50 m), while B. brachychir was generally more abundant on the outer shelf (50-100 m). In general, the three species showed a carcinophagous diet, but with small overlap in their main preys. While amphipods was the most important prey to B. brachychir, isopods and shrimps were the basic food item found in P. nudigula and P. punctatus diet, respectively. This reduction in interspecific competition for food was followed by some degree of spatial segregation and thermal preferences for each species. [ABSTRACT FROM AUTHOR]

Bottom-hole temperatures and physical properties derived from geophysical logs of deep oil wells have been employed in assessment of the geothermal field of the Campos basin, situated in the continental margin of southeast Brazil. The results indicate geothermal gradients in the range of 24 to 41°C/km and crustal heat flow in the range of 30 to 100mW/m² within the study area. Maps of the regional distributions of these parameters point to arc-shaped northeast-southwest trending belts of relatively high gradients and heat flow in the central part of the Campos basin. This anomalous geothermal belt is coincident with the areas of occurrences of oil deposits. The present study also reports progress obtained in reconstructing the subsidence history of sedimentary strata at six localities within the Campos basin. The results point to episodes of crustal extension with magnitudes of 1.3 to 2, while extensions of subcrustal layers are in the range of 2 to 3. Thermal models indicate high heat flow during the initial stages of basin evolution. Maturation indices point to depths of oil generation greater than 3 km. The age of peak oil generation, allowing for variable time scales for cooling of the extended lithosphere, is found to be less than 40Ma. [ABSTRACT FROM AUTHOR]

Abstract: Large potentials for CO2 storage were demonstrated in previous studies in Brazil. This study aims to estimate the CO2 storage capacity in the Campos Basin's oil fields, Southeast Brazil, in order to provide refined values to support CCS planning in the country. The results, based on field/reservoir level data show that there is a large potential for CO2 storage (ca. 950Mt) in the 17 assessed oil fields in the basin, and 75% of this storage capacity is found in sandstone reservoirs. [Copyright &y& Elsevier]

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.)