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The main objective of this work is to analyze the consequences of eutrophication in benthic meiofaunal organisms (foraminifera) in an internal area of Sepetiba Bay (State of Rio de Janeiro, SE, Brazil). This study is interesting because, at the studied site, the sediments corresponding to the period of greatest accumulation of organic matter were not contaminated by metals, although Sepetiba Bay has areas known to be polluted by this type of contaminants. Thus, in this study, it was possible to consider only the impact caused by eutrophication. In the SP6 core, collected in the Sepetiba Bay internal area and studied in this work, textural, geochemical (concentration of chemical elements; 210 Pb and 137 Cs; radiocarbon data) and foraminifera were analyzed in a muddy section, with a few intercalations of sandy layers. The sediments of the analyzed section were deposited in the last ≈2,350 BP years. The concentrations of Al, Cd, Co, Fe, Mn, Ni, Pb, Sn, Ti, V and Zn are higher at the base of the core and decrease towards the top. The contents of TOC, P and Zr have inverse paterns. The ratios of these elements to their background value have similar patterns. However, previous studies have recognized that during the twentieth century Cd, Zn, Cr and Pb concentrations increased in several areas of Sepetiba Bay, mainly due to industrial activity. The area where this core was collected may have been dredged. Radiocarbon ages suggest a loss of ≈2000 years of sedimentary registration, marked by an unconformity at a depth of 126 cm, probably caused by dredging. A new sedimentary sequence unpolluted by metals but highly enriched in organic matter was deposited on the surface of that discontinuity. Foraminifera were quite abundants in the lower section (240-126 cm; between ≈2,400-2,090 years BP, execept in the sandy layers), corresponding to sediment deposition before dredging. After dredging, the accumulation of very fine-grained sediments rich in organic matter generated eutrophication phenomena, which caused a drastic reduction in the abundance and diversity of these organisms. This work testifies the effect of eutrophication on meiofaunal organisms. Although some coastal foraminifer species tolerate harmful effects caused by eutrophication, it is recognized that the impact has been so negative that even these species occur with reduced abundance in the study area. IMPACTO DA EUTROFICACAO EM FORAMINIFEROS BENTONICOS NA BAIA DE SEPETIBA (ESTADO DO RIO DE JANEIRO, SE BRASIL) Resumo O principal objetivo deste trabalho e analisar as consequencias da eutrofizacao em organismos meiofaunais bentonicos (foraminiferos) em uma area interna da Baia de Sepetiba (Estado do Rio de Janeiro, SE, Brasil). Este estudo e interessante porque, no local estudado, os sedimentos correspondentes ao periodo de maior acumulacao de materia orgânica, nao estavam contaminados por metais, apesar da Baia de Sepetiba ter areas reconhecidamente poluidas por este tipo de contaminantes. Assim neste estudo foi possivel considerar apenas o impacto causado pela eutrofizacao. No testemunho SP6, coletado na area interna da Baia de Sepetiba e estudado neste trabalho, foram analisados dados texturais, geoquimicos (concentracao de elementos quimicos; 210 Pb e 137 Cs; dados de radiocarbono) e foraminiferos numa seccao lamosa, com intercalacoes de camadas arenosas. Os sedimentos da secao analisada foram depositados nos ultimos 2.350 anos BP. As concentracoes de Al, Cd, Co, Fe, Mn, Ni, Pb, Sn, Ti, V e Zn sao mais elevadas na base do testemunho e diminuem em direcao ao topo. O conteudo de TOC, P e Zr possui padroes inversos. As razoes destes elementos com o respectivo valor de fundo possuem padroes semelhantes. Porem, estudos anteriores reconheceram em varias areas da Baia de Sepetiba um aumento das concentracoes de Cd, Zn, Cr e Pb durante o seculo XX, principalmente devido a atividade industrial. A area onde foi coletado este testemunho podera ter sido dragada. As idades de radiocarbono sugerem uma perda de aproximadamente 2000 anos de registro sedimentar, marcada por uma inconformidade a 126 cm de profundidade, causada provavelmente por dragagem. Uma nova sequencia sedimentar nao poluida por metais, mas bastante enriquecida em materia orgânica foi depositada sobre a superficie da descontinuidade. Os foraminiferos eram relativamente abundantes na secao inferior (240-126 cm; entre ≈2.400-2.090 anos BP), correspondente a deposicao de sedimentos antes da dragagem. Apos a dragagem, a acumulacao de sedimentos muito finos e ricos em materia orgânica, gerou fenomenos de eutrofizacao, que terao causado uma reducao drastica da abundância e diversidade destes organismos. Este trabalho testemunha o efeito da eutrofizacao em organismos meiofaunais. Apesar de algumas especies de foraminiferos costeiros tolerarem efeitos nefastos causados pela eutrofizacao, reconhece-se que o impacto foi tao negativo que mesmo estas especies ocorrem com abundância reduzida na area estudada. Palavras-chave: Area Costeira. Registro Paleoambiental. Impacto Antropico. Meiofauna, Abordagem Multiproxy.

The present research was developed aiming to study macroscopically the effects of karstification that, over the time, affected significantly the carbonated massif in Khózuè, Cheringoma Plateau (Mozambique). The research was carried out from a field study (collecting samples and photos) for a period of one week, in May of 2017, in Khózuè. During the field work, evidences found in nature were recorded as well as, the mode of occurrence of several structures (caves, dolines and speleothems). The karstification in the study area that occurs in the Cheringoma Formation (from Middle Eocene) was greatly conditioned by fractures which influenced the process and formation of caves and dolines. These structures tended to follow morphological patterns depending on guide fractures orientation allied to their genesis and creating, in certain cases, dolines with a cross morphology. In addition to caves and dolines, karstic activity in the Cheringoma Formation massif also created other structures, especially speleothems, which are not widespread, and also preservation/fossilization of plant remains by mineralization. Chemical weathering chemical weathering, but especially internal geodynamic phenomena transformed the Khózuè massif one karst region with peculiar characteristics. ResumoEste trabalho foi desenvolvido com o objetivo de estudar macroscopicamente os efeitos da carstificação que, com o tempo, afetaram significativamente o maciço carbonatado de Khózuè, no platô de Cheringoma (Moçambique). A pesquisa foi realizada a partir de um estudo de campo (coleta de amostras e fotografias), em 2017, em Khózuè. Durante as atividades de campo, foram analisadas as estruturas encontradas na área de estudo, tal como a ocorrência de falhas, cavernas, dolinas e espeleotemas. A carstificação na área de estudo, associada á Formação Cheringoma (do Eoceno Médio), foi muito influenciada por falhas. Estas favoreceram a formação de cavernas e dolinas. Essas estruturas tenderam a assumir padrões morfológicos condicionados pela orientação de falhas. Em certos casos, as falhas deram origem por exemplo a dolinas em forma de cruz. Além de cavernas e dolinas, a atividade cárstica no maciço da Formação Cheringoma deu lugar também a outras estruturas, como por exemplo, espeleotemas encontrados em apenas alguns locais e a processos de preservação/fossilização por mineralização de restos vegetais. A meteorização química, mas sobretudo fenómenos de geodinâmica interna transformaram o maciço calcário de Khózuè uma região cárstica com características peculiares. Palavras-chave: Karstificação. Cavernas. Dolinas. Espeleotemas. Fossilização. Fraturas.

The Petroleum Terminal Pipeline “Dutos e Terminais do Centro Sul (DTCS)” is one of the largest petroleum terminals in Brazil. To assess wastewater treatment efficiency of the DTCS and to evaluate the contamination by potentially toxic elements (PTE) of sediments, ten sampling points were studied near the riser output of the submarine outfall in the summer of 2005, 2006 and 2007, and ten sampling points were studied along the São Sebastião Channel (CSS). All data were above the standards required by the Brazilian salt water/brackish Water Directives (CONAMA Resolution 454/2012). However, the sediments near the submarine outfall were enriched by As and Cu, with concentrations exceeding the threshold effect level (TEL). In 2005 and 2006, the concentrations of Ba, Sr, Ni and Pb exceeded the values established by TEL in some places. Concentrations of As were 69 times higher than that measured in the background station. In 2007, all the analyzed metals almost doubled the concentrations of that found in 2005. High concentrations of PTE in the sediments, namely Ba and As, are a source of contamination that should be considered for the water quality management planning of the DTCS system. Avaliação da Contaminação por Elementos Químicos Potencialmente Tóxicos (PTE) dos Sedimentos da Região do Terminal Petrolífero “Dutos e Terminais do Centro Sul (DTCS)”, SP, Brasil ResumoO Terminal Petrolífero “Dutos e Terminais do Centro Sul (DTCS)”, SP, Brasil é um dos maiores terminais de petróleo do Brasil. Para avaliar a eficiência do tratamento de águas residuais do DTCS e estimar a contaminação por elementos potencialmente tóxicos (PTE) dos sedimentos, foram estudados dez pontos de amostragem perto da saída do ducto submarino no verão de 2005, 2006 e 2007 e dez pontos de amostragem ao longo do Canal de São Sebastião (CSS). Todos os dados estavam acima dos padrões exigidos pelas Diretrizes Brasileiras para Águas Salgadas/Salobras (Resolução CONAMA 454/2012). No entanto, os sedimentos perto do exutor submarino estavam enriquecidos por As e Cu, tendo as concentrações excedido o nível limiar de efeito (TEL; the threshold effect level). Em 2005 e 2006, as concentrações de Ba, Sr, Ni e Pb ultrapassaram os valores estabelecidos para o TEL. As concentrações de As foram 69 vezes superiores às medidas na estação de fundo. Em 2007, todos os PTE tinham quase duplicado as concentrações de 2005. As altas concentrações de PTE nos sedimentos, nomeadamente Ba e As, são uma fonte de contaminação que deve ser considerada no planejamento da gestão da qualidade da água do sistema DTCS. Palavras-chaves: Elementos Químicos Potencialmente Tóxicos. Sedimentos. Emissários Submarinos. Efluentes Petroquímicos.

The coastal areas, the most populated regions in the world, are those which have undergone the greatest human influence. In Brazilian southeastern coast, the region around Guanabara Bay (GB) is one of the most densely populated, with large cities, such as Rio de Janeiro and Niteroi, and is highly industrialized. Due to anthropic activities tones of effluents, waste and sewage is daily released in GB. Despite, several works have been performed aiming to study the current and past human influence in GB, the sources of pollutants that have impacted this bay since the late nineteenth century. This work is a new contribution aiming to identify the main sources of pollution in the northern/northeast region of GB using stable isotopes of lead (Pb) and metal concentrations during the last decades. It analyses results obtained along the core T3 collected in the northeast region of Guanabara Bay, near the Guapimirim Environmental Protected Area (known as Apa de Guapimirim), a mangrove fringe. Twenty-two sediment samples collected along this core were submitted to grain size, total organic carbon content (TOC), elemental concentrations (Ag, Ca, Cu, P, Pb, S and Zn) and stable isotopes of lead (Pb) analyses. The sediment accumulation rate was estimated by 210 Pb. Results of core T3 were compared with similar data acquired in core T8, collected in Guanabara Bay, at north of Paqueta island. The comparison of the geochemical results allowed to verify that both cores recorded the same reality. Previous works have shown that the northern/northeast region of Guanabara Bay is low polluted by metals, however, since the ≈1950 a marked increase in eutrophication and metal contamination and another noticeable pulse after ≈1970, were recorded in both cores studied in this work. The 206 Pb/ 207 Pb values suggest that the main source of pollutants to northern/northeast region of GB since the second half of the 20 th century have been related to deforestation and landfill and embankment engineering works preformed around the GB, in addition to mineral products applied in industrial goods, as well as oil, agricultural and organic loads. FONTES DE POLUENTES NA AREA NORTE / NORDESTE DA BAIA DE GUANABARA (SE, BRASIL), DESDE O SECULO XIX, COM BASE EM ISOTOPOS DE CHUMBO E CONCENTRACOES DE METAIS Resumo As areas costeiras, as mais populosas do mundo, sao as que tem recebido a maior influencia humana. No litoral sudeste brasileiro, a regiao em torno da Baia de Guanabara (GB), uma das mais densamente povoadas, com grandes cidades, como Rio de Janeiro e Niteroi, e altamente industrializada. Devido as atividades antropicas toneladas de efluentes, residuos e esgoto sao liberados diariamente na GB. Apesar de varios trabalhos terem sido realizados com o objetivo de estudar a influencia humana atual e passada na GB, nao se sabe quais tem sido as fontes de poluentes mais impactantes nesta baia desde o final do seculo XIX. Assim, este trabalho tem como principal objetivo identificar as principais fontes de poluicao na regiao norte / nordeste da GB usando isotopos estaveis de chumbo (Pb) e concentracoes de metais nas ultimas decadas. Analisa os resultados obtidos ao longo do testemunho T3, coletado na regiao nordeste da Baia de Guanabara, proximo a Area Ambiental Protegida de Guapimirim (conhecida como Apa de Guapimirim), uma orla de mangue. Vinte e duas amostras de sedimentos coletadas ao longo deste testemunho foram submetidas a analises granulometricas, teor de carbono orgânico total (COT), concentracoes elementares (Ag, Ca, Cu, P, Pb, S e Zn) e isotopos estaveis de chumbo (Pb). A taxa de acumulacao de sedimentos foi estimada com Pb 210 . Os resultados do testemunho T3 foram comparados com dados semelhantes adquiridos no testemunho T8, coletado na Baia de Guanabara, a norte da ilha de Paqueta. A comparacao dos resultados geoquimicos permitiu verificar que os dois testemunhos registram a mesma realidade. Trabalhos anteriores mostraram que a regiao norte / nordeste da Baia de Guanabara e pouco poluida por metais, no entanto, observou-se nos dois testemunhos que desde 1950 aumentou acentuadamente a eutrofizacao e a concentracao de metais tendo ocorrido um outro pulso de contaminacao depois de 1970. Os valores de 206 Pb / 207 Pb sugerem que as principais fontes de poluentes na regiao norte / nordeste da GB, desde a segunda metade do seculo 20, estiveram relacionadas com o desmatamento e aterros em torno da GB, alem de minerais aplicados em produtos industrias, e ainda petroleo, produtos aplicados na agricultura e materia orgânica. Palavras-chave: Concentracao de metais. Isotopos de Pb. Contaminacao. Fontes de poluicao. Litoral. Registro antropogenico.

This work analyses lead concentrations and isotope ratios 204 Pb, 206 Pb, 207 Pb, 208 Pb, determined by leaching and total dissolution techniques from surface bottom sediment samples collected in the western sector of Sepetiba Bay, Rio de Janeiro (SE Brazil). The main aim of this work was to identify possible sources of Pb, particularly those related to anthropogenic activities for the study area located in the external region of this bay. Isotope ratios of 206 Pb, 207 Pb ranged from 1.160 to 1.259 for the total dissolution technique and from 1.175 to 1.188 for the leaching technique. The Pb isotope signature of the surface sediments of the western sector of Sepetiba Bay were compared with that obtained in other studies performed in Sepetiba Bay, including records of pre- and pos-industrial activity, and in other Brazilian regions. The isotope signature of the analyzed sediments in the western sector of Sepetiba Bay is similar to that obtained in previous works realized in the eastern and northeastern internal region of this bay which is under strong urbanization and industrial pressure. The results of Pb isotope signature obtained by the integrated use of total dissolution and leaching techniques allowed to trace the presence of sediments dredged from highly contaminated areas located in the eastern and north-eastern internal region of Sepetiba Bay probably as a consequence of dredging activities and natural processes of sediment dispersion. IMPACTOS ANTROPOGENICOS NO SETOR OESTE DA BAIA DE SEPETIBA (SE DO BRASIL) ACESSADOS PELA COMPOSICAO ISOTOPICA DE PB DE SEDIMENTOS SUPERFICIAIS Resumo Este trabalho analisa as concentracoes de chumbo (Pb) e isotopos de Pb ( 204 Pb, 206Pb, 207 Pb, 208 Pb) determinados por tecnicas de lixiviacao e dissolucao total de amostras de sedimentos de fundo, coletadas no setor oeste (regiao externa) da Baia de Sepetiba, no Rio de Janeiro (SE Brasil). O principal objetivo deste trabalho foi identificar possiveis fontes de Pb, principalmente aquelas relacionadas a atividades antropogenicas na area de estudo. A assinatura do isotopo Pb dos sedimentos analisados foi comparada com os dados obtidos em outros estudos realizados na Baia de Sepetiba e em outras regioes brasileiras, incluindo registros de atividade pre e pos-industrial. Na regiao externa da Baia de Sepetiba, os valores de 206 Pb/ 207 Pb variaram de 1.160 a 1.259 para a tecnica de dissolucao total e de 1.175 a 1.188 para a tecnica de lixiviacao. A assinatura isotopica dos sedimentos analisados e semelhante a obtida em trabalhos anteriores realizados na regiao interna leste e nordeste desta baia, que esta sob forte influencia da urbanizacao e pressao industrial. Os resultados da assinatura dos isotopos de Pb obtidos pelo uso integrado das tecnicas de dissolucao total e lixiviacao permitiram rastrear, no setor oeste (regiao externa) da Baia de Sepetiba, a presenca de sedimentos provinientes de areas altamente contaminadas localizadas na regiao interna leste e nordeste da baia de Sepetiba, provavelmente como consequencia das atividades de dragagem e processos naturais de dispersao de sedimentos. Palavras-chave: Isotopos de Pb. Geoquimica. Atividades antropogenicas. Fonte de sedimentos. Impacto de dragagem. Litoral.

The section between the 7 and 11 electric markers in the Aratu Stage of the Reconcavo Basin (Lower Cretaceous) has been studied in order to perform a stratigraphic analysis. This section bear reservoir rocks known as Imbe, Cambuqui and Miranga sandstones. It produces petroleum in fields like Miranga, Aracas, Taquipe, Miranga Norte and Imbe. The isopach map showed a general trend of increased subsidence for south and southeast. A series of structural lows surround the platform region known as Quirico High. Southwestward, the Taquipe Canyon is an indication of the lake deepening in that region. In terms of depositional systems, it was interpreted that the Aratu Stage presented a river-dominated deltaic system all over its depositional history. In the proximal regions, located to the north and northwest, the main facies belong to the fluvial and delta plain associations and to the delta front and prodelta in the most distal system. The isolithic map and the sand percentage map indicates a main axial sand distribution. The main sedimentary inflow comes from north and northwest. Near the southeastern faulted border there is a slight contribution from the alluvial fans attached to the Salvador fault. As a natural consequence, the stratigraphic sections showed a decrease of sand south and southeastward as well as the Spontaneous Potential (SP) logs indicate a progressive change from fluvial (normal bell shapes) to deltaic patterns (inverted bell shapes). The sedimentary cyclicity is strongly depicted in the Aratu section. Part of it can be observed in resistivity and SP logs, where auto-correlation can be obtained. Peaks in the resistivity logs indicate lag deposits due to periodic lake flooding. The resistivity value, as a function of the thickness of ostracodal and fish remains calciferous sandstones and shales, allows to separate several orders of peaks (four to six orders). Conventional cyclicity analyses indicate clearly an orbital control due to precession and axial obliquity. The calculated sedimentation ratio is 60 cm/1000 years, and the time interval of 1.44 Ma for deposition of the entire section. ANALISE ESTRATIGRAFICA DO ANDAR ARATU (CRETACIO INFERIOR), BACIA RECONCAVO (BRASIL), COM ROCHAS RESERVATORIO DE HIDROCARBONETOS Este trabalho efetua uma analise estratigrafica da secao entre os marcos eletricos 7 e 11, no Andar Aratu, da Bacia do Reconcavo (Cretaceo Inferior). Esta secao possui rochas reservatorio conhecidas como arenitos de Imbe, Cambuqui e Miranga. Produz petroleo em campos como Miranga, Aracas, Taquipe, Miranga Norte e Imbe. O mapa de isopacas mostrou uma tendencia geral de aumento da subsidencia para o sul e sudeste. Uma serie de baixos estruturais cercam a regiao da plataforma conhecida como a elevacao Quirico. A sudoeste, o canyon de Taquipe constitui uma indicacao do aprofundamento do lago naquela regiao. Os dados obtidos indicam que o Andar Aratu apresentou um sistema deltaico dominado por rio em toda a sua historia deposicional. Nas regioes proximais, localizadas a norte e noroeste, as principais facies pertencem as associacoes fluvial e planicie deltaica, marcando a area mais distal do sistema deposicional, a frente deltaica e o prodelta. O mapas de isolinhas e de percentagem de areia indicam que a distribuicao de areia e sobretudo axial. O principal influxo sedimentar vem do norte e do noroeste. Perto da fronteira com a falha do sudeste ha uma pequena contribuicao de leques aluviais associados a falha de Salvador. Como consequencia natural, as secoes estratigraficas mostraram um decrescimo de areia para sul e sudeste. Os registros geofisicos de Potencial Espontâneo indicam uma mudanca progressiva dos padroes fluviais (em forma de sino) para padroes deltaicos (em forma de sino invertido). A ciclicidade sedimentar e fortemente representada no Andar Aratu. Parte dela pode ser observada nos registros geofisicos de resistividade e de Potencial Espontâneo. Picos nos registros de resistividade indicam inundacoes periodicas do ambiente lacustre. O valor da resistividade, dependente da espessura de arenitos calcarios e xistos com vestigions de ostracodes e peixes, permite separar varias ordens de picos (quatro a seis ordens). Analises de ciclicidade convencionais indicam claramente um controle orbital devido a precessao e obliquidade axial. A taxa de sedimentacao calculada e de 60 cm / 1000 anos, correspondente ao intervalo de tempo de deposicao de toda a secao (andar Aratu) de 1,44 Ma. Palavras-chave: Exploracao de Petroleo. Mapas de Isopacas. Mapas de Isolinhas. Resistividade. Analises de Ciclicidade. Controle Orbital. Sistemas Deposicionais. Sistema Deltaico Dominado por Rio.

The Lu-Hf method has been used in the investigation of geological samples in order to understand processes and sources of magmatic rocks. This paper discusses the reference materials GJ-01, 91.500 and Mud Tank isotopic composition by LA-ICP-MS to investigate how suitable they are for the zircon analysis through this technique. The results show that the three zircons have homogeneous compositions for the proposed objectives. Considering that relatively high Yb contents produce isobaric interference, the results of this work have shown that the Mud Tank is the best reference material, since it has lower values of this element. Thus, the Mud Tank allows to obtain more reliable results due to lower correction requirements. In addition, it should be emphasized that the presented data corroborate the application of Hf isotopes for geological evolution and characterization of magmatic sources. The high abundances of Hf in the zircon grains allow to preserve the isotopic signatures of its crystallization from magmatic sources, allowing to characterize the isotopic signatures of the reservoir (s) that gave origin to that rocks, and in case studies of paleoclimate and paleoceanographic records and/or of sedimentary basins evolution, it allows to identify the origin of the sediments or temporal and spatial changes of the source of sedimentary particles. COMPOSIÇÃO ISOTÓPICA DE Lu, Hf e Yb ANALISADA POR LA-ICP-MS DOS MATERIAIS DE REFERÊNCIA “GJ-01”, “91.500” e “MUD TANK”: APLICAÇÃO DA GEOCRONOLOGIA Lu-Hf EM ZIRCÃO ResumoO método Lu-Hf tem sido utilizado para entender processos de formação e fontes de rochas magmáticas. Este artigo analisa a composição isotópica por LA-ICP-MS dos materiais de referência GJ-01, 91.500 e Mud Tank para investigar quão adequados eles são para a análise de zircônio através desta técnica. Os resultados mostram que os três zircões possuem composições homogêneas podendo ser usados com materiais de referência para as pesquizas referidas. Considerando que teores relativamente altos de Yb produzem interferência isobárica, os resultados deste trabalho mostraram que o Mud Tank é o melhor material de referência, uma vez que possui os menores valores deste elemento. O Mud Tank permite obter resultados mais confiáveis por requerer menor correção dos valores obtidos. Além disso, deve-se ressaltar que os dados apresentados corroboram a aplicação de isótopos de Hf para a evolução geológica e caracterização de fontes magmáticas. As altas abundâncias de Hf nos grãos de zircão permitem preservar as assinaturas isotópicas de sua cristalização a partir de fontes magmáticas, permitindo caracterizar as assinaturas isotópicas do (s) reservatório (s) que deram origem a essas rochas. Têm também utilidade em estudos de paleoclima e paleoceanográficos e/ou da evolução das bacias sedimentares, permitindo identificar a origem dos sedimentos ou mudanças temporais e espaciais da fonte das partículas sedimentares. Palavras-chave: Método Isotópico Lu-Hf. Interferência isobárica. Análise de Alta Resolução Espacial. Zircão. Calibração de materiais de georeferenciamento. Pesquisa analítica.

Paleoenvironmental reconstructions in coastal environments have been carried out using indicators of relative sea level oscillation (RSL), among them, mollusk shells, beachrocks and sedimentary records. Data from eleven geological-geotechnical drilling cores (from 15 m to 30 m long) distributed along the Ipanema - Leblon coastline and on the edge of the Rodrigo de Freitas Lagoon and respective stratigraphic profiles were analyzed in this work. Eleven radiocarbon ages obtained from shell samples calibrated to eliminate the effect of reservoir were used to perform the time evolution of the study area. The obtained results allowed to identify five distinct stages on the sedimentary evolution of the Southern Zone of the Rio de Janeiro City related to the Holocene RSL variations: the first stage under continental environmental conditions, with sea level approximately 4.5 m below the current; the second stage corresponding to a paleo-cove formed due to the sea level rising; the third stage associated with the mid-Holocene maximum transgression, in which the entire study area was flooded; the fourth stage following the gradual lowering of the RSL and marked by the formation of a paleo-bay; the fifth stage corresponding to the current configuration of the coastline. EVOLUCAO E RECONSTITUICAO PALEO-AMBIENTAL DA ZONA SUL DA CIDADE DO RIO DE JANEIRO (SE BRASIL) Resumo As reconstrucoes paleoambientais em ambientes costeiros tem sido realizadas utilizando indicadores de oscilacao relativa do nivel do mar (NRM), entre eles, conchas de moluscos, beachrocks e registros sedimentares. Foram analisados neste trabalho, dados de onze testemunhos de perfuracao geologico-geotecnica (de 15 m a 30 m de comprimento) distribuidos ao longo do litoral de Ipanema - Leblon e a beira da Lagoa Rodrigo de Freitas e respectivos perfis estratigraficos. Onze idades de radiocarbono calibradas obtidas em amostras de conchas foram utilizadas no estudo da evolucao temporal da area de estudo. Os resultados obtidos permitiram identificar cinco etapas distintas da evolucao sedimentar da Zona Sul da cidade do Rio de Janeiro, relacionadas com variacoes do NRM durante o Holoceno: a primeira etapa, sob a influencia de condicoes ambientais continentais, esta relacionada com um nivel do mar aproximadamente 4,5 m abaixo do atual; a segunda etapa corresponde a uma paleo-enseada formada devido a elevacao do nivel do mar; o terceiro estagio associado a transgressao maxima do Holoceno medio, em que toda a area de estudo foi inundada; o quarto estagio, apos o abaixamento gradual do NRM, e marcado pela formacao de uma paleo-baia; a quinta etapa corresponde a configuracao atual do litoral. Palavras-chave: Mudanca relativa do nivel do mar. Quaternario. Sedimentacao Marinha. Evolucao litoral. Modelo 2D.

This work is based on a compilation of benthic foraminiferal data collected in the Aveiro Lagoon and in the adjacent continental shelf and upper slope (center of Portugal). It intends to provide an overall analysis from transitional to the outer continental shelf of the occurrence and distribution of species in living and to present updated taxonomic data and illustrations of most of the species found in the in the Aveiro Lagoon and in the adjacent continental shelf including in total assemblages. Cluster analysis (CA) and Principal Components Analysis (PCA) interpreted as depth functions allow us to identify the main species in different ecoenvironments and sectors of the study area. The most unusual living assemblage was documented in the lagoon inlet under very strong tidal currents activity, composed mostly by the following species (both in living and total assemblages): Rotaliammina concava, Lepidodeuterammina ochracea, Quinqueloculina seminula , Gavelinopsis praegeri , Paratrochammina haynesi, Remaneica helgolandica and Remaneicella gonzalezi. The distribution patterns of some Trochamminidae and Remaneicidae species whose ecology and distribution pattern are poorly known, have proved to be a marker of more or less hydrodynamic and stable/unstable environments in coastal and transitional marine environments. OCORRENCIA DE FORAMINIFEROS E DISTRIBUICAO DAS PRINCIPAIS ESPECIES NA LAGOA DE AVEIRO E NA PLATAFORMA CONTINENTAL ADJACENTE (PORTUGAL) Resumo Este trabalho baseia-se numa compilacao de dados foraminiferos bentonicos recolhidos na Laguna de Aveiro e na plataforma continental adjacente (centro de Portugal). Pretende efetuar uma analise geral da distribuicao de especies nas associacoes vivas e totais (vivas e mortas) na area de estudo, em funcao da profundidade. Pretende ainda apresentar dados taxonomicos e ilustracoes da maioria das especies encontradas na Laguna de Aveiro e na plataforma continental adjacente. A analise de agrupamento (CA) e a analise de componentes principais (PCA), em funcao da profundidade, permitem identificar as principais especies em diferentes ecossistemas e setores da area de estudo. A associacao viva mais invulgar foi encontrada na embocadura da Laguna de Aveiro, um ambiente sujeito a forte corrente de mare. Essa associacao era composta principalmente pelas seguintes especies (na associacao viva e total): Rotaliammina concava, Lepidodeuterammina ochracea, Quinqueloculina seminula , Gavelinopsis praegeri , Paratrochammina haynesi, Remaneica helgolandica and Remaneicella gonzalezi . Os padroes de distribuicao de algumas especies de Trochamminidae e Remaneicidae, cuja ecologia e padrao de distribuicao sao pouco conhecidos, mostraram ser um marcador de ambientes mais ou menos hidrodinâmicos e de estabilidade/instabilidade do substrato em ambientes marinhos costeiros e de transicao. Palavras-chave: Ecologia. Taxonomia. Imagens digitais. Analise Estatistica. Ambientes Transicionais e Costeiros Marinhos.

This study characterizes the quantity and quality of organic matter present in surface sediments of the NE sector of Guanabara Bay (SE, Brazil), based on geochemical and statistical analysis. The geochemical analyses included stable isotopes in sedimentary bulk organic matter (orgδ13C), total organic carbon (TOC), total sulfur (TS) and Rock Eval pyrolysis parameters, such as free hydrocarbons (S1), generating source potential (S2), production index (PI), oxygen and hydrogen indices (OI, HI) and the maturation index of organic matter (Tmax). The analyzed data were statistically treated to find main factors that are influencing the sedimentary composition. The low activity of the bottom currents favors the deposition of fine-grained sediments, rich in organic matter, in most of the studied area. The organic matter present in the sediments is being supplied by local and allochthonous sources and can be considered a good source of type III kerogen, and therefore has the potential to generate gas, if the geological context is adequate. Considering the quantity, type of organic matter and potential of hydrocarbon generation four main groups of stations were identified. Stations in which the sediments: i) encompass a relatively high component of OM sourced mainly from the adjacent continental areas close to the Apa de Guapimirim (less contaminated by oil) and S. Gonçalo (Roncador River) regions; ii) contain some autochthonous contribution, located between the Paquetá and Governador Islands, where biogenic gas seeping should be predicted hereafter; iii) have higher contamination by oil, situated near Mauá and REDUC Oil Refinery, of Duque de Caxias; iv) present intermediate characteristics, located in the remaining study area.

The use of geochemical normalizers has been applied in sedimentological studies in several study contexts, such as pollution, diagenetic and provenance assessment. Selected textural and mineralogical data of 137 surface sediment samples were compared by statistical analyses with geogenic elements concentrations normalized by the Al, Be, Ce, Fe, Fe+Al, Li, Rb and Sc aiming to identify the best normalizer to trace different sources of bottom sediments for the Aveiro Lagoon entrance (NW of Portugal). The study area is heterogenous in terms of hydrodynamics and sedimentary processes. The most commonly applied geochemical normalizer for the sediments elemental concentrations has been the aluminum. However, the statistical analyses evidenced that the best normalizer was the scandium, since Principal Components Analysis results have evidenced that the element/Sc values are largely independent of sediment granulometry and thus have allowed the identification of compositional differences not related to grain size. Statistical analyses have also allowed to discriminate groups of stations that: i) trace the entry and exit of mixed sources sediments of the lagoon due to the action of tidal currents; ii) contain materials provided from the erosion of granitoids present mainly along the Douro River basin, located to the north, and transported southward by coastal drift; iii) encompasse sediments provided from the erosion of the Schist–Greywacke Complex crossed by the Vouga River that drains into the inner central zone of the lagoon and; iv) represent an area of sediment accumulation located near the entrance of Mira Channel, where lithogenic materials, provided by mixed lithologies in addition to organic matter, are being deposited. The results of this work contribute to the knowledge of the sedimentary dynamics of the Aveiro Lagoon, a coastal system which is part of a littoral stretch that is being strongly eroded, due to natural and anthropic causes and should be applicable to other coastal systems with similar characteristics.

International audience; Dredging is a common and important activity to maintain or improve/extend navigable depths in many ports and harbours. Dredging sometimes occur in areas where the sediments are contaminated material and is subject to consent and licensing according to the national regulations. This work shows the general pattern of distribution of potentially toxic elements (PTEs), such as As, Cd, Co, Cr, Cu, Ni, Pb and Zn, in surface sediments of the Ria de Aveiro lagoon mouth area (Portugal). The work is based on textural, mineralogical and geochemical analysis of 137 surface sediment (first centimetre) samples. The Pollution Load Index (PLI) was used to evaluate the overall enrichment of these elements and the enrichment factor (EF) was determined to assess the degree of anthropogenic input of taking into account the characteristics of the receiving environment and its legitimate use; and one station (29) as slightly contaminated dredged material (Class 3) that may be used for embankments or in the case of soaking requires a thorough study of the place of deposition and subsequent PTEs. Portuguese Ministerial Order n.° 1450/2007 was used as reference to classify dredging and elimination or application of dredging materials. Results evidence that the study area, which is highly anthropized, the concentration of PTEs is largely controlled by the hydrodynamics. The PLI index values show the highest enrichment of metals in the western side of Mira Channel entrance. The EF values indicate that eighty-three stations have significant enrichment of metals particularly Pb and Cr being the significant enrichment by Cr much more common and by Pb punctually. According to the Portuguese regulation most of the sites can be classified as clean dredged material (Class 1), sixteen sites as dredged material with trace contamination (Class 2) that may be immersed in the aquatic environment monitoring. In addition, sediments have an important ecological value.

This work intends to apply new ecological descriptors to a coastal marine area aiming to assess its environmental trophic status. This approach make possible to identify relevant variables associated with eutrophication process applicable and valid worldwide. The aim of this work is to study the organic matter (OM) quality and quantity, in terms of biopolymers, in Saquarema Lagoonal System (SLS) located in Rio de Janeiro State (Brazil). Sediment samples collected in SLS were analyzed in this study for granulometric and geochemical data such as total organic carbon (TOC), total sulfur (TS) and biopolimeric carbon (BPC) concentration, including proteins (PTN), carbohydrates (CHO) and lipids (LIP). These data were combined with additional environmental parameters measured in water of the four linked lagoons that compose the SLS. Data analyses allowed the identification of four distinct regions in SLS: an inner and impacted zone characterized by sediment particularly enriched in TOC, with lowest quality of OM most probably provided by contaminated effluents and rivers runoff; an outer-less impacted lagoonal area with relatively low TOC content and submitted to high hydrodynamic forces; an intermediate area characterized by transitional features between the two previously mentioned and a zone that are influenced mainly by salinity. The organic matter accumulation depends on the hydrodynamic conditions mostly governed by tidal currents. The quality of organic matter seems to be mainly influenced by the water renewal, rivers inputs and mangroves contributions as well as by the autochthonous lagoonal biological productivity. Results of this work indicate that the inner zone of SLS is being affected by eutrophication not necessarily caused by anthropic factors.

Core T4 (with 286 cm long) collected in the inner part of Sepetiba Bay is a record of late Holocene evolution of Sepetiba Bay. This core was described and sampled every 2 cm. Textural, geochemical and foraminifera data were analyzed, and two radiocarbon dates were obtained. Estimated ages indicate that core T4 represents the last ≈4,000 years calibrated before present (yrs cal BP). Results of this core suggest that coarse sediments, recorded in the period between ≈4,000-3,400 yrs cal BP, were probably associated with high hydrodynamic conditions in the study area. These sediments should be deposited at an incipient phase of the Marambaia Beach Barrier evolution; the development of this sand barrier resulted in the confinement of the inner region of Sepetiba Bay, leading to the deposition of muddy sediments rich in organic matter. Organic matter enrichment increased especially in the last ≈500 yrs cal BP. Foraminifera assemblages and carbonates content indicate that the studied region should have been affected in the last ≈3,400 yrs cal BP by changes in the water depth column. An increase of the water column depth was recorded for example between ≈850-350 yrs BP. The results obtained in the core T4 show that the confinement and eutrophication process of the internal zone of Sepetiba Bay, has been occurring since ≈3,400 yrs cal BP and is being caused by other factors such as geomorphological and climatic changes and human activities.

This study intends to evaluate baseline concentrations of chemical elements for unpolluted sediments of Sepetiba Bay (SE Brazil). It analyzes the concentrations of potentially toxic elements (PTE) and other chemical elements (by Inductively Coupled Plasma Mass Spectrometry and Inductively Coupled Plasma Emission Spectrometry) from the upper part of the SP2 drillcore (or 2-SPT-1-RJ; with 50.30 m length), collected on the margins of Sepetiba Bay (at latitude 22° 55'S and longitude 43° 46'W). This core was described and sampled. Textural, mineralogical and geochemical analyses were performed in 17 sediment levels. The sediment layers of interest were selected, considering the period in which they were deposited, before high anthropic influence in the area, and on sediment grain-size. Only the muddy levels were selected, since fine sediments generally tend to have higher elemental concentrations. Foraminiferal occurrence was also analyzed in the selected layers. The results indicate that the studied sediments were deposited in a transitional marine context, after being exposed to multiple sedimentary cycles and weathering. The baseline concentrations, related to natural sediment sources were estimated for As, Cd, Co, Cr, Cu, Ni, Pb, Zn) and P and for other chemical elements. These results are useful in environmental impact assessment not only in the study area, but also for other coastal regions of Rio de Janeiro State. TÍTULO: CONCENTRAÇÕES DE FUNDO DE ELEMENTOS QUÍMICOS NA BAÍA DE SEPETIBA (SE BRASIL) RESUMO:Este estudo pretende avaliar as concentrações de fundo de elementos químicos, em sedimentos não poluídos, na Baía de Sepetiba (Se Brasil). Analisa as concentrações de elementos potencialmente tóxicos (PTE) e outros elementos químicos (por Espectrometria de Massa Plasma Acoplada Indutivamente e Espectrometria de Emissão Plasma Acoplada Indutivamente) da parte superior do testemunho SP2 (ou 2-SPT-1 RJ; com 50,30 m de comprimento), coletado nas margens da Baía de Sepetiba (à latitude 22° 55'S e longitude 43° 46'W). Este testemunho foi descrito e amostrado a cada 5 cm. Análises estruturais, mineralógicas e geoquímicas foram realizadas em 17 níveis de sedimentos. Os níveis de interesse foram selecionados, considerando o período em que foram depositados, antes da alta influência antrópica na área, e no tamanho do grão do sedimento. Apenas os níveis de lama foram selecionados, uma vez que os sedimentos finos tendem geralmente a ter maiores concentrações de elementos quimicos. A ocorrência de foraminíferos foi também analisada nas camadas selecionadas. Os resultados indicam que os sedimentos estudados foram depositados num contexto marinho de transição, após serem expostos a múltiplos ciclos sedimentares e a intemperismo. As concentrações de fundo, relacionadas a fontes naturais de sedimento foram estimadas para As, Cd, Co, Cr, Cu, Ni, Pb, Zn) e P e para outros elementos químicos. Esses resultados são úteis para a avaliação de impacto ambiental, não apenas na área de estudo, mas também em outras regiões costeiras do Estado do Rio de Janeiro. PALAVRAS-CHAVE: Multi-indicadores. Sedimentos. Registros Holocénicos. Litoral. Atlântico Sul.

The disposal of waste and sewage by anthropic activities in Guanabara Bay (GB), Rio de Janeiro State (Brazil) is negatively affected this coastal ecosystem over the last few decades. This research intends to document how organic matter and metal enrichment affect the benthic organisms. Physicochemical, textural, geochemical and microfaunal data (foraminifera) are analyzed in nine stations in the NE sector of Guanabara Bay. The size and structure of the living foraminiferal assemblages are analyzed on each sedimentary fractions (63-150 μm, 150-250 μm, 250-500 μm and >500 μm) of every station. In the fraction >500 μm no foraminifera were found. Results suggest that organic matter contents are high everywhere whereas metals concentrations increase in Sao Goncalo region. The dimension, diversity and equitability of the living foraminiferal assemblages were reduced in the study area. Ammonia tepida was the dominant taxon in all samples. Living specimens identified in the 63-150 μm sedimentary fraction were found at all stations except in front of Sao Goncalo city (stations GB9 and GB8). Most of species were not found in the 250-500 μm sediment fraction in most sites except for instance Ammonia tepida . This species dominate in eutrophic areas but where organic matter is in an oxide stage and regardless of whether there is or not gas seep. Foraminiferal density and diversity increased in areas with a prevalence of organic matter from oceanic biological production and declined in areas where organic matter and metals are retained in disoxic/anoxic phases of the sediments.

This work was performed in the NE region of the Guanabara Bay, a highly impacted Brazilian coastal system, located in Rio de Janeiro State. It aimed to: i) identify and map the areas with occurrence of gas in the sediment, as well as its acoustic signature; ii) characterize the physical properties of the sediments and; iii) document the response of microbenthic organisms (living benthic foraminifera) to changes in quantity and quality of organic matter. Seismic surveys at the frequency of 12 kHz identified a large area with about 50% gas charged sediments in the study area. The main acoustic signatures of the shallow gas were black shadow and gas blanket. In addition, features related to gas seepages to the water column (acoustic plumes and pockmarks) and gas percolation within the sediments (intra-sedimentary plumes, turbidity pinnacles) were also identified. The gas has a biogenic origin and results from the high sedimentation rate between 0.03 to 0.9 cm.year -1 and from the decomposition of large amount of organic matter (10-20%). Vertical distribution of gas ranges from few centimeters to 9 m below the water-sediments interface. These occurrences are related to both gas migration from lower sedimentary layers to Holocene muds above, and to recent generation in near-surface sediments as the area display favorable conditions for gas production. Cores ranging from 150-240 cm in length have predominantly muddy sediments and variations in the P-wave velocity followed the changes in sediment density, controlled mainly by the presence of gas in sediments, bioclasts accumulation, textural variation and percentage of organic matter. The TOC content and Rock-Eval pyrolysis parameters evaluated in nine surface sediment samples indicate that good to excellent amount of organic matter associated with moderate to good source potential for gas production is present in the study area. In these areas living benthic foraminifera are of reduced diversity and density. The assemblages are largely dominated by Ammonia tepida . Statistical results evidence that areas of intense gas release affect the benthic faunas since the benthic foraminiferal assemblages are reduced in diversity and density.

The variety of approaches for assessing the trophic environmental state indicates that there is a strong need for the identification of new and possibly integrated ecological descriptors in coastal marine areas. These approaches would be able to capture relevant variables associated with the eutrophication process, and would be reliable, applicable and valid worldwide. The main objective of this study was to provide evidence that the quantity of total organic carbon (TOC), total sulfur (TS) and biopolymeric carbon (BPC) is useful proxies to evaluate the benthic trophic status in transitional marine environments. Sediment samples collected in Itaipu Lagoon, a Brazilian coastal system of the State of Rio de Janeiro, were analyzed in this study. Geochemical data, such as TOC, TS and BPC concentrations, including proteins (PTN), carbohydrates (CHO) and lipids (LIP), are combined with additional environmental parameters of the bottom water measured in in Itaipu Lagoon. The analysis of quantity and quality of organic matter (OM) allowed the identification of three distinct regions in Itaipu Lagoon: an inner and impacted zone characterized by sediment particularly enriched in TOC, with lower quality of OM most probably provided by the contaminated effluents and rivers runoff; an outer-less impacted lagoonal area with relatively low TOC content where the highest values of BPC/TOC and PTN/TOC are indicative of the presence of OM with high nutritional quality; and an intermediate area characterized by transitional features between the two previously described. The organic matter accumulation depends on the hydrodynamic conditions mostly governed by tidal currents. The quality of organic matter seems to be mainly influenced by municipal effluents, rivers inputs and mangroves contributions as well as by the autochthonous lagoonal biological productivity. Results of this work indicate that the inner zone of Itaipu Lagoon is being affected by eutrophication.

Graphic Computer and the three dimensional technique (3D) has its applicability in various fields of science, such as: medicine, zoology, botany and paleontology. In the paleontology field it has been applied, mainly in the study of vertebrates and invertebrates fossils. The 3D-models of the scanned fossils by computed microtomography (micro-CT) allow to observe full details of its internal and external morphology. The three-dimensional model of the species provides great detailing of internal and external structures, which can contribute to a better understanding and characterization of morphological features of the analyzed materials. This work aims to detail the morphology of Pyrgo depressa (d’Orbigny, 1826) (benthic foraminifera) using the micro-CT technics. Results of imagens and of the 3D-modells obtained by micro-CT analysis allowed the observation of the initial and later chambers arrangement, the proloculus with a columnar structure and two apertures, the sequence and linearization of the apertures and toothplates of the following chambers, the walls thickness and density. The 3D-models also allow to deduce the function of teeth which is related to the initial formation of the peripheral keel.

The Guadiana River is the fourth longest river in Europe and is a natural frontier between southern Portugal and Spain. This river was historically used to transport minerals exploited in the region since the Roman Empire and therefore suffered human interventions that have been intensified after the industrial revolution. The Guadiana River has in its limits the Guadiana Valley Natural Park, which is of great value for the Conservation of Geobiodiversity. This study mainly aims to identify zones with the environmental characteristics in the estuarine area of the Guadiana River based on the distribution and ecology of microorganisms (ostracods and foraminifera) associated with physicochemical parameters and sedimentological and geochemical (carbohydrate, lipid, protein, total organic carbon and total sulfur) data. Fifty-five foraminifera taxa were identified along the estuary with dominance of Ammonia tepida and Miliammina fusca and 13 ostracods taxa with dominance Leptocythere lacertosa and Loxoconcha elliptica . Detrended correspondence analysis (DCA) performed using biotic and abiotic variables indicated that pH, grain size, total organic carbon (TOC) and lipids were the most influent factors in the distribution of these organisms. Four zones were identified in the Guadiana River estuary: i) Low estuary - region with the largest marine influence with sandy sediment, higher salinity and total sulfur and mainly represented by the dominance of estuarine species of foraminifera ( Ammonia tepida and Cribroelphidium vadescens ) and by the ostracods ( Darwinula stevensoni , Semicytherura sulcate and Urocythereis oblonga ); ii) Intermediate estuary - region characterized by neutral pH and sandy sediment enriched in carbohydrates; this region is characterized by the presence of the ostracods species Cytherois fischeri and Neocytherideis subulata and by calcareous and agglutinated species in foraminiferal assemblages; iii) Upper estuary - silt, high TOC, proteins and lipids content, and by the presence of Loxoconcha elliptica ; iv) Freshwater environment - has similar characteristics to the upper estuary, but do not display foraminifera and was composed of ostracod species such as Cyclocypris ovum , Heterocypris incongruens and Ilyocypris sp. These species are commonly found in freshwater environments or in waters with very low salinity. The predetermined limit in previous studies for the intermediate/upper estuary shifted approximately 5 km further north. This effect may be due to human influence, since a dam was built on the river decreasing the freshwater flow and allowing marine water entrance to an inner area of the estuary. doi: 10.12957/jse.2016.22534

This work is based on the study of the core T1 collected in the Guaratiba Mangrove, located on the northeastern margin of Sepetiba Bay. Few studies dealing with the application of benthic foraminifera to study sea level changes during the Holocene have been conducted in Sepetiba Bay, State of Rio de Janeiro, Brazil. In order to fill this gap, the core T1 was studied using textural, geochemical (carbonate, total organic carbon, total sulfur and stable isotopes evaluated in Ammonia tepida ) and microfaunal (benthic foraminifera) data, unveiling paleoecological relationships of these organisms and the evolutionary scenario of Guaratiba Mangrove. Radiocarbon results indicate an estimated age of about 2400 yrs cal BP for the core base. Textural, geochemical and benthic foraminifera data suggest that the study area changed significantly during the last 2400 yrs cal BP. It experienced coastal waves action and shoreface processes in the period between ≈2.400-1.400 yrs cal BP; then, this phase gave place to a shallow marine environment similar to that found currently in internal and protected areas of Sepetiba Bay, between ≈1.400-350 yrs cal BP. Thenceforth, the study area evolved to the present mangrove environment. Factors related to climatic oscillations and the formation, evolution and events of rupture of Marambaia sand ridge influenced the late Holocene evolution of the northeast intertidal area of Sepetiba Bay. doi: 10.12957/jse.2016.21924

The main objective of this work is to locate and identify the outcrops considered iconic and valuable as references, not only from the point of view of Cultural or Didactic Tourism, but also in paleoenvironmental reconstruction studies, based on the lithologies that comprise the Itarare Group, in the State of Sao Paulo, Brazil. This work also intends to relate these sites to outcrops of sedimentary facies, in an area located at south of Itu and Porto Feliz, and north of Sorocaba. The Itarare Group lies within the Parana Basin (Paleozoic), and is composed by sedimentary sequences associated with the record of the Permo-Carboniferous glaciation event that occurred in the Gondwana supercontinent. This work is based on observations of outcrops in a macro- and mesoscopic scale, considering the characterization of external and internal aspects of the layer, the stratigraphic sequence in the outcrop, and the continuity of the layers within the mapped area. The study area has outcrops where the evidences of glaciomarine deposits predominate. Sedimentary sequences deposited in a subaquatic low-energy environment, as well as episodic deposits, in which relatively more energetic phases alternated with low hydrodynamic conditions are well-developed in the study area. There are also fluvio-deltaic environmental occurrences related to sea level oscillations linked with glacier advances and receding. doi: 10.12957/jse.2016.21964

Two high-resolution multi-proxy records from cores collected in the upwelling regions off Cabo Frio (Brazil, core 7620) and Galicia (NW Iberian Peninsula, core KSGX40) were used to evaluate environmental changes during the Holocene. Core 7620 is a muddy sequence that exhibits gradual coarsening upward and covers a time period of approximately 9400 yr cal BP. Core KSGX40 records the last 4800 yr cal BP and consists of a sedimentary sequence exhibiting gradual fining upward in grain size. Results from core 7620 indicate that important changes occurred at 7000, 5800 and 3000 yr cal BP. Micropaleontological proxies indicate an increase in organic carbon supply towards the bottom, due to higher oceanic productivity, in the last 2500 yr cal BP. This increment in oceanic productivity is likely related to stronger upwelling events in the Cabo Frio region in that period. Core KSGX40 also indicates an increment in upwelling events in the Galicia region in the last 2500 yr cal BP. In both systems, the upwelling is linked to the intensification of NE winds and the prevalence of relatively drier climatic conditions. The Holocene upwelling changes in the Cabo Frio region were previously attributed to deviations in the position of the Inter-Tropical Convergence Zone (ITCZ), whereas in the Galician area this phenomenon was attributed to alterations in the North Atlantic Oscillation (NAO). The multi-millennial variability recorded in both cores suggests the occurrence of Holocene in-phase climatic changes both in Southern Hemisphere at the latitudes of the SW coast of Brazil (Cabo Frio region) and in the Northern Hemisphere, at the latitude of Galicia (NW Iberian Margin). These coupled climatic alterations were probably related to changes in the oceanic-atmospheric climatic systems, coupled with and amplified by solar forcing effects. doi: 10.12957/jse.2016.21463

Foraminifera and thecamoebians assemblages were analyzed at Caete River Estuary in order to identify saline gradients and intensity of human impacts. In the study area, 29 species of foraminifera typically from intertidal environments and 11 species of thecamoebians were identified. The microfaunal assemblages were characterized by low diversity, averaging 1.9 at the mouth and 0.5 near Braganca City. These values are common in transitional coastal environments along de Brazilian Coast. Statistical analysis, based on the relative abundance of species, did not reveal the presence of an estuarine gradient, which was corroborated by the physical and chemical parameters measured in the field. An increasing of sedimentary fine fraction and organic matter occurs in the intermediate region of the estuary, indicating attenuation of the stream influence. The calcareous foraminifera species were associated with high salinity, temperature and pH values. The agglutinated species were associated with muddy sediment, total organic matter and lower salinity. Four environmental compartments were identified based on biotic and abiotic analysis, but they do not represent the classic estuarine gradient, instead, they represent the differences in the freshwater supply and mangrove distance. doi: 10.12957/jse.2016.21264

This work aims to compare the dimensions and composition of benthic foraminiferal biocenoses (living specimens) during two summer sampling events. Forty-four sediment samples were collected on the Aveiro Continental Shelf (Center of Portugal) (latitude of 40o30'N-40o50'N, longitude of 8o46'W-9o20'W) for granulometry, total organic matter (TOM) and living foraminiferal analyses. The sediment samples were collected during summers of 1994 and 1995, on stations located along transects (east-west direction) and between the bathymetries of 10-200 m. During the sampling campaigns, measurements of salinity, temperature and density data were recorded in the water column. The results showed that the living assemblages were mainly found in stations located between 20-80 m depth. The abundance of living foraminifera was generally reduced at depths

International audience; The Bizerte Lagoon (Tunisia) functions as a sedimentation environment characterized by receiving allochthonous sediments mainly transported by the Ben Hassine, Rharek and Guenich streams, as well as marine sediments from the Mediterranean Sea. It is subjected to significantenvironmental changes due to the natural and anthropic influences altering the natural patterns of circulation, extraction and/or deposition of mineralogical materials. The aim of this investigation is to analyze the sediments supply and early diagenetic processes in Bizerte Lagoon. Thephyicochemical parameter of the sediment pore water, as well as their texture, mineralogical composition (X-Ray diffraction technique - XRD), magnetic susceptibility and their geochemical composition (namely lithogenic and evidence a coarser particles contribution of the Ben Hassinestream to the lagoon. The other streams seem to introduce mostly fine grained sediments in the lagoon. The currents circulation, the water residence time and the biological productivity influence the mineralogical and geochemical characteristics of the bottom sediments. The industrialactivity is also an important factor, since it results in the accumulation of high levels of some metals, such as Fe. Metals are mostly retained in the sediment in areas with active biogeochemical activity due to high organic matter accumulation. Mineralogical and geochemical patterns biogenic chemical elements analyzed by ICP-MS) were analyzed in 10 sampling stations. The water temperature with an average of 15.2°C was stablein the study area. The sediments were generally characterized by fine granulometry, mainly mud and sandy mud, poorly to very poorly sorted, and constituted by two or more granulometric particle modes. The mineralogical results revealed the presence of phyllosilicates, quartz, pyrite, calcite, anatase and K-feldspar, and other minerals in smaller proportions. The fine sediment and high phyllosilicates and Al contents indicate the presence of weak currents in most part of the studied area. The results of sorting, skewness and kurtosis suggest that the currents are more active in the northern region of the lagoon, near the channel of communication with the Mediterranean Sea. They also indicate contributions from different rocks sources, diverse processes of transport and deposition of sediments and varied processes of production of autochthonous materials

Total organic carbon (TOC), total sulfur (S) and Rock-Eval pyrolysis analyzes were performed in 41 samples collected along the SP-60-PR core, from the Irati Formation, northwestern of Parana Basin. This work aims to show how organic matter content evolved vertically in the Irati Formation and therefore to contribute to the identification of the most attractive levels to generate hydrocarbons, in thermally immature sediments. The results of these analyses allowed to recognize sharp changes in the types of organic matter and paleoenvironmental conditions, giving rise to eight chemical- stratigraphic units, labeled as A, B and C (Taquaral Member) and D, E, F, G and H (Assistencia Member). The units A and C display low organic carbon content and predominance of organic matter type IV, which indicate an oxic environment. The unit B, with higher TOC content, has organic matter predominantly of type II and should be associated to a disoxic environment. The Assistencia Member, mainly with organic matter type II, is differentiated from the previous units by their sharply higher TOC content and hydrogen index values, suggesting a more restricted environment, characterized by disoxic to anoxic conditions. The bituminous shale of the units E and H have the highest TOC, sulfur and hydrogen index values, representing the units where conditions of the autochthonous organic matter (type II) preservation was more efficient (anoxic environment). Despite being found organic matter thermally immature in the Assistencia Member, the layer with the highest generation potential is the unity H. The comparison with data of other studied wells evidenced a strong reduction in the potential generator of the Irati Formation toward the north of Parana Basin.

Itarare Group represents the glacial record of Gondwana Continent in the intracratonic Parana Basin, encompassing regions of Southern Brazil, Eastern Paraguay, Northeast Argentina and Northern Paraguay. Itarare Group is the thickest sedimentary package of Parana Basin, and was deposited over 36 million years during the end of the Carboniferous and the beginning of the Permian. However, in relation to its paleoenvironmental evolution, it is generally understood that more research is necessary, in order to better understand the genesis of the Itarare Group in different places. The present work entailed mapping facies associations for the Itarare Group in the city of Salto, in Sao Paulo State, by identifying and classifying sedimentary facies that, in turn, were utilized to develop a paleoenvironmental evolution model. This model was based on geological mapping carried out over 125 km². Petrological and petrographic descriptions of 32 outcrops of Itarare Group also were studied. These results were compared with subsurface data obtained by Sistema de Informacoes de Aguas Subterrâneas, Servicos Geologicos do Brasil (SIAGAS-CPRM; System Water Information Groundwater, Geological Survey of Brazil). Through lithofacies and petrographic analyses and making a comparison between five column sections, surface and subsurface data, a stratigraphic correlation model was established for the region. Through this model was possible to identify four facies associations, which, together, indicate how the paleoenvironmental evolution of the region occurred. The first three associations (A, B, C) were interpreted as being formed in subaqueous environment, being related to sandy lobe systems, followed by the last association (D), pertaining to a fluvial system. doi: 10.12957/jse.2016.21956

It is with great satisfaction that we disclose the creation of Journal of Sedimentary Environments (JSE), an open access journal that allows online publication of important articles in the fields of Sedimentology, Stratigraphy, Paleontology, Archeology, Biology (associated with sedimentary environments), Speleology, Biogeography, Oceanography, Environmental Sciences, Geophysics, Geochemistry, Energy Resources and related fields. The JSE was designed by the Department of Stratigraphy and Paleontology (DEPA), Faculty of Geology (FGEL) at the State University of Rio de Janeiro (UERJ) in order to fill a gap in Brazilian geoscientific research: the absence of a focused journal for the area of Sedimentary Geology. Given the representativeness and authority of the Brazilian community in this field of research, it is of fundamental importance to create a channel for communication and integration between Brazilian and foreign geoscientists. We believe that the JSE will play an important role in this process. The JSE is a quarterly journal (four issues per year) in English and rigorously peer-reviewed. Its editorial board is composed of renowned national and foreign researchers from different areas of Sedimentary Geology, which are also editors of important journals focused on geosciences worldwide. The creation of the JSE is also a tribute to the great masters of Sedimentary Geology who had and have a very important role, not only for the Faculty of Geology at UERJ and for Rio de Janeiro State, but also for Brazilian Geology: Maria Antonieta da Conceição Rodrigues, Hernani Aquini Fernandes Chaves, Jorge Carlos Della Fávera, Pedro de Césero (in memoriam) and René Rodrigues.

This work studies mineralogical data from X-Ray Diffraction Techniques (XRD) and geochemical data analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) of fine fraction from samples collected along the Ocean Margin Exchange Project (OMEX) core KSGX 24. This core was recovered in the external sector of Ria de Vigo, N Spain. Radiocarbon ages allowed the estimation of an age about 3 ka cal BP for the core base. Core KSGX 24 is a muddy sedimentary sequence with two main sections where the sediments are finer: ≈134-90 cm and ≈26-0 cm. These finer sections are characterized by a relatively low sedimentation rate, and by changes in the geochemical and mineralogical composition of the sediments and their magnetic susceptibility. Basically, they are relatively depleted in carbonates and Ca content, and relatively enriched in detrital minerals, namely phyllosilicates, and in Al, Co and Sc. The slightly coarser grained intercalated sections are marked by the increase of Ce, La and Th content. These results suggests that, despite the prevalence of a weak hydrodynamic regime in the study area during the last 3 ka, it has undergone some changes. The mineralogical and geochemical deviations may have been conditioned by several factors, such as: authigenetic and diagenetic reactions; anthropogenic activities in the nearby continental region; the natural tendency for sea level rise; changes in hydrodynamic conditions regulated by modifications in the pattern of prevailing winds; and alterations in the rainfall regime. The two last factors are related to climate oscillations and probably with the tendency of the North Atlantic Oscillation (NAO) to remain more positive or negative during longer periods in the past than at present. doi: 10.12957/jse.2016.21642

The main goal of this work is to analyze the elemental composition of the test’s wall of some species/specimens of Textulariids (sub-class Subclass Textulariia), collected in surface sediments of the NW Iberian Margin. The elemental analyses was based on the Energy Dispersive Spectroscopy (EDS) on the Scanning Electron Microscope (SEM; Hitachi, S4100) of Textularia deltoidea, Textularia agglutinans, Sahulia conica, Karrerotextularia flintii, Siphotextularia heterostoma, Karreriella bradyi, Spiroplectammina sagittula and Arenoparrella mexicana . The elelemetal cocnentrations of the species wall were compared with the mineralogical composition (X-Ray diffraction) of the sediments of the stations where these specimens were collected. The results evidence that whereas the test’s wall of T. deltoidea , T. agglutinans , K. flintii and S. heterostoma are characterized by the highest concentrations of Ca, Mg and Y and lowest Si and Al contents; S. conica, S. sagittula and K. bradyi present intermediate concentrations of the refereed variables but display the highest K content; A. mexicana , contains the highest Si and Al contents and lowest Ca, Mg and Y concentrations. Some species that live in silisiclastic sediments contains high calcium content in their tests (such as T. deltoidea , T. agglutinans whereas some species much common in the deep sea includes high concentrations of lithogenic elements. Results of this work suggests that some Textulariid species can use the test for “storage” and “excretion” of toxic or useless elements that can be used when necessary. These features seems to be functions of biomineralization of the analyzed species and not only the intention of built a protective envelope.

This work focuses on the distribution and the controlling factors of rare earth element (REE) total concentrations and fractionation patterns in fine sediment fractions of 53 samples collected along the main channels of the Ria de Aveiro, a northern Portuguese coastal lagoon. Total and available concentrations and residual phases of REE and total concentrations in three chemically partitioned fractions (S1 - adsorbed by clay and co-precipitated with carbonates; S2 - adsorbed by organic matter; S3 - adsorbed by amorphous Mn hydroxides) are analysed. These data are joinly analysed with physicochemical, textural and mineralogical and other geochemical data. Sediment samples mainly consisted of phyllosilicates, quartz, plagioclase and K–feldspars. Cerium (Ce) is the most abundant REE in the residual phase and displays the lowest total available percentage, whereas Yttrium (Y) is the most available. The highest total concentration and residual concentration (R) of Ce, Lanthanum (La), Scandium (Sc) and Y are mostly related to fine grained sediments, suggesting that their distributions are conditioned by lagoon hydrodynamics. The dissimilar distribution of REE-S1, REE-S2 and REES3 indicates differentiated sedimentary processes. The enrichment of REE-S2 and REE-S3 is related essentially to biogeochemical processes inside the lagoon. The REE-S1, as well as Ce-S1/Sc-R, trace sediments supplied from the northern areas suplyed mostly by the Douro River outflow and from the Antua River. In the past, the sediments suplyed by the Douro River through the litoral drift contributed to the formation of the lagoon islands. Thus the relatatively high Ce-S1/Sc-R values inside the lagoon allowed the identification of: sediments supplied from the litoral drift and deposited near the lagoon mouth, erosional processes of the lagoonal islands and sediments supplied by the Antua River. This work demonstrates that the available concentrations of rare earth elements can be considered as important tools for investigating sediment sources and dispersion in a coastal system. doi: 10.12957/jse.2016.21444

Surface sediment samples recovered in the Sao Paulo Bight (SW Atlantic) were collected between 45 to 1132 m water depths to characterize sedimentary processes based on a multiproxy approach. This study analysis benthic foraminifera and abiotic data, including granulometry, TOC and C/N values. Spatial and yearly distributions of ocean chlorophyll -a concentrations [Chl-a] evaluated from available SeaWiFS Chlorophyll Ocean Colour Images also were analyzed. On the basis of the non-metric Multidimensional Scaling analysis two regions with different characteristics were identified (1) Sao Sebastiao Island and (2) Grande Island. The C/N results indicate that in most of the studied stations the organic matter supplied to the sea bottom is provided essentially by oceanic productivity. Concentrations of chlorophyll -a and TOC are higher in Grande Island region than in the Sao Sebastiao Island sector. In the first region the benthic foraminifera assemblages are larger but less diversified than in Sao Sebastiao Island sector. The foraminifera assemblages of Grande Island region are dominated by Globocassidulina subglobosa and composed mostly by opportunist species related to episodic availability of food inputs related to the Cabo Frio upwelling system. The influence of this system seems to decrease in Sao Sebastiao Island sector. In the deeper slope stations of the Sao Sebastiao Island region, the presence of an arborescent community ( Rhadammina spp. and Rhizammina spp.) and Nodulina dentaliniformis suggests that the sedimentary regime is relatively more stable and contain a higher amount of refractory organic than in Grande Island region for the similar range of depths.

Guanabara Bay (GB), located at the coast of Rio de Janeiro State (Brazil), is an ecosystem rich in biodiversity both in terms of mega, macro and microfauna. However, the factors that control their distribution are still poorly understood. This work intends to identify the possible factors affecting the distribution of benthic foraminifera in the bay by comparing living and dead assemblages in selected sediment fractions. Substantial differences in terms of density, diversity and equitability of the species in the living and dead assemblages and in different sediment fractions (63-150 μm, 150-250 μm, 250-500 μm) are identified. Lower similarity (