The present paper aims to investigate the relative sea-level and the coastal evolution during the Holocene in the Rio de Janeiro coastline, based on geological and biological indicators. Using topographic survey, excavation and coring, and 14 C dating of these coastal deposits and beachrocks outcrops, we have reconstructed a sealevel curve for the Holocene. For the first time on the Brazilian coast it was identified a negative record of relative sea-level during Late Pleistocene and Early Holocene transition. After the transition, a relatively rapid increase of sea-level began. At approximately at 8500 cal yr BP, the sea-level was 0.5 m below the current level, was overtaken for the first time in the Holocene, at approximately 7500 cal yr BP. The maximum level of +2.5 m was reached between 4770 and 4490 cal yr BP. At the point of maximum transgression, the sealevel began a general behavior of lowering until the present. These results confirm other data already obtained elsewhere along the Atlantic coast of South America. The results of this study are consistent with previous researches and they help to refine the Holocene sea-level record along the Brazilian coast.

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The Southwest Atlantic continental margin between latitudes 21 and 23°S comprises the Campos Basin area. Its continental shelf is some 100 km wide, with the slope starting between 80 and 130 m in depth. The slope is about 40 km wide, extending deeper to the south (2000 m) than to the north (1500 m). Water masses influencing the area include (1) surficial tropical water (TW), 250 to 300 m depth; (2) South Atlantic central water (SACW), below TW 300 to 550 m; (3) Antarctic intermediate water (AIW), between 550 and 1200 m depth; and (4) North Atlantic deep water (NADW), 1200 to 3500 m depth. Distributions of octocorals (25 genera, 32 species/morphotypes) and stony corals (27, 11) and associations among taxa and with water masses were analyzed. Different communities were found over 3 depth ranges. Complete dissimilarity was observed between the continental shelf margin/upper slope and the middle-lower slope. The shallower depth range (52 to 760 m) was influenced by TW, SACW and the upper limit of AIW, while 11 species/morphotypes occurred exclusively in the middle depths (1000 to 1200 m), under the sole influence of AIW. No species were exclusive to the deepest depth range (1200 to 1605 m), which is bathed by NADW. Middle slope areas were distinct from one another, while lower slope areas were more homogeneous. Co-occurrences of species indicate the type of environment they live in, as soft or hard bottoms.

The Caraja ´s Province presents several volcano-sedimentary sequences that comprise the Itacaiu ´nas Supergroup. The rocks represent bimodal volcanism, and clastic and chemical sedimentation in relatively unstable basins subject to recurrent structural events with subsidence and volcanism. The Gra ˜o Para ´Group represents one of these sequences with mafic volcanic rocks that enclose discontinuous jaspilite lenses, with development of large high-grade orebodies (Fe.65%). This unit is named the Caraja ´s Formation and presents peculiar characteristics compared with other iron districts in the world, thereby departing from the classic Lake Superior or Algoma iron formation types. Owing to the dense vegetation, lack of outcrops and harsh landscape, the structural analysis of the district can only be accomplished by combination of regional field work, detailed structural work on the open pits and remotely sensed image interpretation, in this case Landsat ETM7, JERS-1 images and the shuttle radar topography mission (SRTM) digital terrane model. The regional trend of the several sequences of the area is approximately N-S and the structure is dominated by a flattened flexural fold system with axes moderately dipping WNW, intersected by several strike-slip faults subparallel to their axial plane. The Serra dos Caraja ´s represents an s-shaped synform-antiform pair, herein named the Caraja ´s Fold. This regional structure is partially disrupted by the Caraja ´s Shear Zone that divides it in the northern (Serra Norte) and the southern (Serra Sul) Ranges and also probably prepared the terrane with the development of pathways for mineralising hydrothermal fluids forming large highgrade massive iron bodies. Syntectonic granitic bodies played an important role in the structural evolution of the area as well. They caused localised ductile flattening deformation and thermal contact metamorphism in surrounding terranes. The Estrela pluton, for instance, was responsible for the discontinuity of the regional trend between the Serras do Rabo and Leste. The Caraja ´s Province is regionally the upper crustal product of a very shallowly eroded dome-and-keel geometry of Neo-Archaean volcano-sedimentary units intruded by syntectonic calc-alkaline intrusives and overlying pre-existing infracrustal rocks. The lithostructural data suggest continental-margin back-arc basin development and closure in an oblique collision belt, with N-S shallow crustal shortening, parallel to the inferred pre-existing strike of the stratigraphy.

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Abstract. The formation of the Paraíba do Sul river delta plain on the coast of Rio de Janeiro state, Brazil, gave rise to diverse lagoons formed under different sea level regimes and climate variations. Sedimentary core lithology, organic matter geochemistry, and isotopic composition (δ13C and δ15N) were analyzed to interpret the sedimentation of the paleoenvironment of the Lagoa Salgada carbonate system. Different lithofacies reflect variations in the depositional environment. The abundance of silt and clay between 5.8 and 3.7 kyr enhances the interpretation of a transgressive system, which promoted the stagnation of coarse sediment deposition due to coast drowning. Geochemistry data from this period (5.8–3.7 kyr) suggest the dominance of a wet climate with an increase of C3 plants and a marked dry event between 4.2 and 3.8 kyr. This dryer event also matches with previously published records from around the world, indicating a global event at 4.2 ka. Between 3.8 and 1.5 kyr, Lagoa Salgada was isolated; sand and silt arrived at the system by erosion with the retreat of the ocean and less fluvial drainage. Geochemistry from this moment marks the changes to favorable conditions for microorganisms active in the precipitation of carbonates, forming microbial mats and stromatolites in the drier phase.

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