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A dificuldade na distinção entre areias fluviais e marinhas não é incomum, principalmente em litorais com pouco aporte sedimentar e com planícies muito próximas à área fonte. Este estudo objetiva caracterizar os sedimentos de superfície das planícies flúvio-marinhas da região de Vitória (ES) e inferir sobre os processos deposicionais e a origem das areias com base nos parâmetros sedimentológicos (granulometria, composição, mineralogia e morfoscopia dos grãos de quartzo) e morfológicos. Os sedimentos foram distinguidos em depósitos arenosos e de terras úmidas. Apesar da imaturidade textural, os depósitos arenosos foram classificados em fluviais e marinhos. Contudo, os parâmetros sedimentológicos não foram suficientes para sanar dúvidas de proveniência em algumas amostras. Neste caso, a ausência de feições morfológicas bem definidas dos depósitos arenosos como alinhamento de cristas arenosas são recursos importantes para uma interpretação paleoambiental, especialmente quando os parâmetros sedimentológicos parecem ser ambíguos. The difficulty in distinguishing between fluvial and marine sands is not uncommon, especially in coastal areas with little sedimentary input and plains very close to the source area. This study aims to characterize the surface sediments of the fluvial-marine plains in the region of Vitória, state of Espírito Santo (ES), and to infer about the depositional processes and the origin of the sands based on the sedimentological (grain size, composition, mineralogy and morphoscopy of quartz grains) and morphological parameters. Sediments were distinguished in sandy and wetland deposits. Despite the textural immaturity, the sandy deposits were classified as fluvial and marine. However, the sedimentological parameters were not sufficient to resolve doubts of provenance in some samples. In this case, the absence of morphological features in sandy deposits or particular shapes such as alignment of sandy ridges are important resources for a paleoenvironmental interpretation, especially when sedimentological parameters appear to be ambiguous. La distinción entre las arenas fluviales y marinas no es una tarea facil, en particular en las costas con baja fuente sedimentaria, además en llanuras donde la región de origen del sedimentos son muy cercanas de la región de deposición. El estudio tiene como el objetivo caracterizar los sedimentos superficiales de las llanuras fluviomarinas de la Región de Vitória (ES) e inferir los procesos de deposición y el origen de las arenas en función de parámetros sedimentológicos (tamaño de grano, composición, mineralogía y morfoscopia de granos de cuarzo) y morfológicos. Los sedimentos se distinguieron en depósitos arenosos y de tierras humedales. Apesarar de la baja madurez textural, los depósitos arenosos se clasificaron como depósitos fluviales y marinos. Luego los parámetros texturales no fueron suficientes para responder a las questiones de proveniencia en algunos sedimentos. Todavía, la ausencia de informaciones morfológicas definidas de los depósitos arenosos, como la orientación de las líneas arenosas, no ayudó nas interpretaciones yaque son recursos importantes para una interpretación paleoambiental, en particular cuando los parámetros sedimentológicos parecen ser inciertos. La difficulté de faire la distinction entre les sables fluviaux et marins n'est pas rare, en particulier dans les zones côtières à faible apport sédimentaire et avec des plaines très proches de la zone source. Cette étude vise à caractériser les sédiments de surface des plaines fluvio-marines de la région de Vitória, état d'Espírito Santo (ES), et à en déduire les processus de dépôt et l'origine des sables à partir des paramètres sédimentologiques (granulométrie, composition, minéralogie et morphoscopie des grains de quartz) et morphologiques. Les sédiments ont été distingués dans les dépôts sableux et humides. Malgré l'immaturité de la texture, les dépôts sableux ont été classés comme fluviaux et marins. Cependant, les paramètres sédimentologiques n'étaient pas suffisants pour dissiper les doutes sur la provenance de certains échantillons. Dans ce cas, l'absence de caractéristiques morphologiques dans les dépôts sableux ou de formes particulières comme l'alignement de crêtes sableuses sont des ressources importantes pour une interprétation paléoenvironnementale, surtout lorsque les paramètres sédimentologiques semblent ambigus.

This study presents new sedimentology data and attempts to understand coastal processes, sedimentary dynamics and stratigraphic patterns of the Rio Bonito Formation (early Permian) in Parana Basin, southern Brazil. The study was performed based on the description of five cores, located in a small-scale area - Sao Gabriel City - in Rio Grande do Sul State, southern Brazil. Eighteen facies were described and grouped into nine facies associations. Later, these facies associations were then grouped into three depositional systems: fluvial, tide-dominated estuary and wave-dominated shallow-marine depositional systems. A paleoenvironmental evolution is proposed using three block diagrams showing the paleoenvironmental stage (S1, S2, and S3). S1 contains the oldest part of the sedimentary record with predominance of fluvial system deposits, S2 comprises dominantly estuarine system deposits, and S3 is mostly composed of shallow-marine deposits. ­Stratigraphic framework showed a general retrogradacional tendency, with thickness variations along the systems tracts that allowed for the construction of a curve of accommodation changes to the Rio Bonito Formation in the region of Sao Gabriel during the early Permian. This study contributes to a better understanding of the fluvial discharges, tidal and oscillatory (wave) currents and their interactions and dominances along stratigraphic records of coastal deposits.

Una de las singularidades del paisaje costero de Galicia es la amplia presencia de depósitos edafo-­‐sedimentarios cuaternarios, de extraordinaria calidad en cuanto a la información que aportan. Una diferencia respecto al ámbito atlántico europeo. Registran la memoria de la tierra y pueden contemplarse como archivos que documentan cambios paleo-­‐ambientales a escala local, regional y global y contextos geomorfológicos relacionados con la historia humana. Imbuido por una renovada concepción del patrimonio, que valora las formaciones naturales más allá de su apreciación estética, el pensamiento científico ha comenzado a considerar estos depósitos como un bien patrimonial. Sin embargo, se produce una total desconexión entre estas aspiraciones y el reconocimiento de administración y ciudadanía. Desde la convicción de que solo se producirá un reajuste a través de una educación generadora de conciencia social sobre los paisajes geomorfológicos, en este trabajo se plantea la relevancia de una educación patrimonial de índole crítica; se propone un modelo de actuación focalizado en la formación inicial del profesorado y se avanzan algunos datos que muestren sus resultados. One of the distinctive features of the coastal landscape of Galicia is its great number of quaternary pedosedimentary deposits, which are of extraordinary quality in terms of the information which, they provide, making them stand out from the rest of the European Atlantic coast. They record the memory of the land and can be considered to be repositories documenting paleoenvironmental changes on local, regional and global levels, as well as geomorphological contexts related with human history. Imbued with a renewed understanding of heritage, which values natural formations beyond the appreciation of their aesthetic aspect, scientific thinking has begun to consider these deposits as cultural assets. However, a total disconnection arises between these aspirations and the recognition of such assets by the political administration and citizens. In the belief that a change in this situation will only be brought about via an education which generates a social conscience regarding geomorphological landscapes, this study examines the relevance of a form of heritage education which is critical in nature; an approach focused on initial teacher training is proposed and data showing the results of this approach are presented. Este artículo se ha realizado en el marco del proyecto COMDEMO (EDU2015-­‐65621-­‐C3-­‐1-­‐R) que cuenta con financiación del Plan Nacional de I+D del Gobierno de España y Fondos FEDER de la UE SI

Una de las singularidades del paisaje costero de Galicia es la amplia presencia de depósitos edafo-­‐sedimentarios cuaternarios, de extraordinaria calidad en cuanto a la información que aportan. Una diferencia respecto al ámbito atlántico europeo. Registran la memoria de la tierra y pueden contemplarse como archivos que documentan cambios paleo-­‐ambientales a escala local, regional y global y contextos geomorfológicos relacionados con la historia humana. Imbuido por una renovada concepción del patrimonio, que valora las formaciones naturales más allá de su apreciación estética, el pensamiento científico ha comenzado a considerar estos depósitos como un bien patrimonial. Sin embargo, se produce una total desconexión entre estas aspiraciones y el reconocimiento de administración y ciudadanía. Desde la convicción de que solo se producirá un reajuste a través de una educación generadora de conciencia social sobre los paisajes geomorfológicos, en este trabajo se plantea la relevancia de una educación patrimonial de índole crítica; se propone un modelo de actuación focalizado en la formación inicial del profesorado y se avanzan algunos datos que muestren sus resultados. One of the distinctive features of the coastal landscape of Galicia is its great number of quaternary pedosedimentary deposits, which are of extraordinary quality in terms of the information which, they provide, making them stand out from the rest of the European Atlantic coast. They record the memory of the land and can be considered to be repositories documenting paleoenvironmental changes on local, regional and global levels, as well as geomorphological contexts related with human history. Imbued with a renewed understanding of heritage, which values natural formations beyond the appreciation of their aesthetic aspect, scientific thinking has begun to consider these deposits as cultural assets. However, a total disconnection arises between these aspirations and the recognition of such assets by the political administration and citizens. In the belief that a change in this situation will only be brought about via an education which generates a social conscience regarding geomorphological landscapes, this study examines the relevance of a form of heritage education which is critical in nature; an approach focused on initial teacher training is proposed and data showing the results of this approach are presented.

The determination of hydraulic conductivity is a relevant topic for the characterization of widely-extended sandy coastal deposits. In the present work, the hydraulic conductivity of the Rimini Northern coastal deposits is evaluated through different procedures. Hydraulic conductivity is estimated from in situ and laboratory tests on small soil volumes, and from empirical correlations based on particle size distribution and in-situ tests. Relying on the variability ranges of the estimated parameters, a preliminary numerical water flow model of the testing area has been developed. Results can be considered as predictive of the hydraulic behavior of large soil volumes in the investigated area.

The topic of this thesis is the Origin of the Dutch coastal landscapes during the Holocene. The landscape evolution is visualized in a series of palaeogeographical maps, and the driving mechanisms behind the environmental changes are discussed. The practice to make palaeogeographical map reconstructions in the Netherlands developed after the Second World War when a lot of regional geological and soil scientific mapping programs were carried out by government institutions and universities. The palaeogeographical map reconstructions were subsequently used for the understanding and modelling of the long-term coastal evolution, coastal management issues, landscape-archaeological purposes and for education and public information. The aim of this thesis is to describe how the palaeogeographical maps are compiled, what kind of data was used and what the goals were which had to be achieved with the maps. Palaeogeographical maps can be drawn on three scale levels: national, regional and local. The format of this book follows this subdivision. Geoarchaeology is involved in all these studies. Geological and palaeo-environmental data from archaeological excavations and surveys, ‘key sites’ in the landscape reconstruction, provided essential information for the palaeogeographical reconstructions. In the introduction (Chapter 1) the background of the landscape reconstructions is given, the geological / palaeo-environmental terminology and stratigraphic classifications are discussed, the role of archaeology in the coastal reconstruction treated, and the driving mechanisms in coastal evolution are elaborated upon. Chapter 2 discusses the compilation of 11 palaeogeographical maps of the Netherlands. Chapter 3 reports about three regional palaeogeographical studies. The flooding history of the Southwestern Netherlands is described in Chapter 3.1. The landscape history of the Oer-IJ tidal system (middle Noord-Holland) is the subject of Chapter 3.2. The landscape development of this system is described on a regional to supra-regional scale. In Chapter 3.3 five landscape reconstructions of the coastal area of the Northern Netherlands and Lower Saxony between 500 BC and today are presented. Three local palaeogeographical case studies are described in Chapter 4. The Yangtze harbour (water connection between the Maasvlakte 1 and 2; Port of Rotterdam) study is an example of a research in which geology and palaeolandscape reconstructions were used as tools for archaeological prospection of potential Stone-Age archaeology in the subsurface of the harbour (Chapter 4.1). The study of the Vergulde Hand West in Vlaardingen (VHW; Chapter 4.2) describes the landscape development of a peat site along the northern margin of the Rhine–Meuse Estuary. At this location archaeological remains from the Bronze Age up to the Middle Ages were found. The landscape evolution around a Middle Bronze Age site in the area of Geestmerambacht, north of Alkmaar, is the subject of Chapter 4.3. The area was part of the former Westfriese tidal-inlet system and the archaeological site is located on top of a salt-marsh ridge. In the synthesis, Chapter 5, the landscape development of the Netherlands is summarized. For the time intervals between the different national palaeogeographical maps, the mechanisms driving coastal evolution are analysed.

The topic of this thesis is the Origin of the Dutch coastal landscapes during the Holocene. The landscape evolution is visualized in a series of palaeogeographical maps, and the driving mechanisms behind the environmental changes are discussed. The practice to make palaeogeographical map reconstructions in the Netherlands developed after the Second World War when a lot of regional geological and soil scientific mapping programs were carried out by government institutions and universities. The palaeogeographical map reconstructions were subsequently used for the understanding and modelling of the long-term coastal evolution, coastal management issues, landscape-archaeological purposes and for education and public information. The aim of this thesis is to describe how the palaeogeographical maps are compiled, what kind of data was used and what the goals were which had to be achieved with the maps. Palaeogeographical maps can be drawn on three scale levels: national, regional and local. The format of this book follows this subdivision. Geoarchaeology is involved in all these studies. Geological and palaeo-environmental data from archaeological excavations and surveys, ‘key sites’ in the landscape reconstruction, provided essential information for the palaeogeographical reconstructions. In the introduction (Chapter 1) the background of the landscape reconstructions is given, the geological / palaeo-environmental terminology and stratigraphic classifications are discussed, the role of archaeology in the coastal reconstruction treated, and the driving mechanisms in coastal evolution are elaborated upon. Chapter 2 discusses the compilation of 11 palaeogeographical maps of the Netherlands. Chapter 3 reports about three regional palaeogeographical studies. The flooding history of the Southwestern Netherlands is described in Chapter 3.1. The landscape history of the Oer-IJ tidal system (middle Noord-Holland) is the subject of Chapter 3.2. The landscape development of this system is described on a regional to supra-regional scale. In Chapter 3.3 five landscape reconstructions of the coastal area of the Northern Netherlands and Lower Saxony between 500 BC and today are presented. Three local palaeogeographical case studies are described in Chapter 4. The Yangtze harbour (water connection between the Maasvlakte 1 and 2; Port of Rotterdam) study is an example of a research in which geology and palaeolandscape reconstructions were used as tools for archaeological prospection of potential Stone-Age archaeology in the subsurface of the harbour (Chapter 4.1). The study of the Vergulde Hand West in Vlaardingen (VHW; Chapter 4.2) describes the landscape development of a peat site along the northern margin of the Rhine–Meuse Estuary. At this location archaeological remains from the Bronze Age up to the Middle Ages were found. The landscape evolution around a Middle Bronze Age site in the area of Geestmerambacht, north of Alkmaar, is the subject of Chapter 4.3. The area was part of the former Westfriese tidal-inlet system and the archaeological site is located on top of a salt-marsh ridge. In the synthesis, Chapter 5, the landscape development of the Netherlands is summarized. For the time intervals between the different national palaeogeographical maps, the mechanisms driving coastal evolution are analysed.

Submitted by CARLA MARIA GOULART DE MORAES (carlagm) on 2015-04-01T20:11:18Z No. of bitstreams: 1 RosanaGandiniGeologia.pdf: 4608662 bytes, checksum: 062ac1345c53f4c87b0c0423e27c5022 (MD5) Made available in DSpace on 2015-04-01T20:11:18Z (GMT). No. of bitstreams: 1 RosanaGandiniGeologia.pdf: 4608662 bytes, checksum: 062ac1345c53f4c87b0c0423e27c5022 (MD5) Previous issue date: 2008-11-04 CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Ambientes marginais marinhos são áreas em constante transição que limitam o desenvolvimento das biotas. Fatores ecológicos limitantes da vida bentônica como salinidade, oxigenação, energia e exposição do substrato, condicionam o comportamento dos organismos. A salinidade atua nestes meios como um regulador natural na distribuição da fauna e sua flutuação, combinada aos demais fatores ambientais, resulta em condições fisiologicamente estressantes para muitos organismos. Os depósitos de subsuperfície da sucessão sedimentar Rio Bonito no bloco central da jazida carbonífera de Iruí (Cachoeira do Sul, RS) contêm as icnofábricas de Chondrites, Chondrites-Helmintopsis-Planolites, Cylindrichnus-Thalassinoides, Helminthopsis, Macaronichnus, Ophiomorpha, Palaeophycus, Planolites, Thalassinoides, Thalassinoides-Palaeophycus e Thalassinoides-Palaeophycus-Helminthopsis, distribuídas em associações de fácies representativas de depósitos costeiros e marinhos rasos. As icnofábricas presentes nos depósitos costeiros são caracterizadas pelo baixo índice de bioturbação, pelo tamanho reduzido das escavações e pela baixa icnodiversidade, enquanto que a de depósitos marinhos rasos apresenta moderado a alto índice de bioturbação e maior icnodiversidade. O padrão de cada icnofábrica, sua distribuição estratigráfica e seus vínculos faciológicos permitiram reconhecer quatro assinaturas icnológicas principais, três indicativas de estresse por salinidade e uma substrato-controlada. As icnofábricas de Helmithopsis, Palapeophycus e Planolites presentes na litofácies SiltArg sugerem o domínio de águas oligoalinas a doces. As icnofábricas de Thalassinoides-Palaeophycus e Cylindrichnus-Thalassinoides refletem domínio de águas mesoalinas, representando, respectivamente, uma suíte de ambientes mais estáveis e com menor energia (suíte empobrecida de Icnofácies Cruziana) e uma suíte de ambiente com maior energia (suíte de Icnofácies mista Skolithos-Cruziana). A icnofábrica Thalassinoides-Palaeophycus-Helminthopsis caracteriza uma suíte marinha rasa de Icnofácies Cruziana arquetípica; o tamanho reduzido das escavações, contudo, sugere domínio de águas polialinas, e a ocorrência pontual das icnofábricas, deposição em enseadas, que mimetizariam as condições ambientais encontradas na zona de shoreface inferior/transição ao offshore. A icnofábrica de Thalassinoides é substratocontrolada e ocorre em contexto de Icnofácies Glossifungites, demarcando superfícies estratigráficas autocíclicas nas seqüências C e D e uma superfície estratigráfica alocíclica que separa as seqüências basais da seqüência E. A análise integrada da sedimentologia e da icnologia dos depósitos estudados, em alta resolução, permitiu refinar as interpretações paleoambientais e estratigráficas pré-existentes para a sucessão sedimentar Rio Bonito na área de estudo. Marginal-marine environments are permanently transitional areas, constraining the biocoenosis development. Ecological features such as salinity gradient, available oxygen content, energy in biotope and substrate consistency and exposure control the animal behavior and impact in the establishment of benthic life. In these environments, the salinity gradient works as a natural regulator of faunal distribution and its fluctuation, combined with the afore mentioned features, results in stressing physiological conditions for many organisms. Thus, the biogenic sedimentary structures produced by the endobenthic fauna in these environments commonly reflect this stress. The subsurface deposits of the Rio Bonito sedimentary succession in the central block of the Iruí coal mine (Cachoeira do Sul, Rio Grande do Sul State, southern Brazil) is composed of sedimentary facies associations that represent deposition in dominantly marginal marine and shallow marine settings, the later in minor scale. Ichnofabrics of Chondrites, Chondrites-Helmintopsis-Planolites, Cylindrichnus-Thalassinoides, Helminthopsis, Macaronichnus, Ophiomorpha, Palaeophycus, Planolites, Thalassinoides, and Thalassinoides-Palaeophycus occur in the marginal marine settings, while the Thalassinoides-Palaeophycus-Helminthopsis ichnofabric is present in the shallow marine deposits. The marginal-marine ichnofabrics are characterized by the low bioturbation index, the reduced size of burrows, and the low ichnodiversity, whereas the marine ones show a moderate to high degree of bioturbation and ichnodiversity. The ichnofabric pattern, its stratigraphic distribution, and its sedimentological relationships allow recognizing four ichnological signatures, three suggesting stress caused by changes in the salinity gradient, and one substratecontrolled. Ichnofabrics of Helmithopsis, Palapeophycus, and Planolites in lithofacies SiltArg suggest the dominance of oligohaline to freshwater conditions. Ichnofabrics of Thalassinoides-Palaeophycus and Cylindrichnus-Thalassinoides reflect the dominance of mesohaline conditions, each one representing, respectively, more calm and stable environments (impoverished Cruziana Ichnofacies suite), and moderate to high energy settings (mixed Skolithos-Cruziana Ichnofacies suite). The Thalassinoides-Palaeophycus-Helminthopsis ichnofabric represents an arquetypical Cruziana Ichnofacies suite, indicating shallow marine settings. The reduced size of the burrows, however, suggests dominance of polyhaline rather than stenohaline conditions and its local distribution allow infer deposition in embayments, which mimic the environmental conditions found in the lower shoreface/offshore transition zones. The Thalassinoides ichnofabric is substrate controlled, representing Glossifungites Ichnofacies suítes. It demarcates autocyclic stratigraphic surfaces in sequences C and D, and an allocyclic stratigraphic surface (sequence boundary) that separates the basal sequences from the sequence E. The integrated analysis of the ichnology and sedimentology of the studied deposits, in high resolution scale, allowed refine the pre-existent paleoenvironmental and stratigraphic interpretations of the Rio Bonito sedimentary succession in the study area.

A sand dune located near São Bento do Norte and Caiçara do Norte towns (northern coastal region of Rio Grande do Norte state, Northeastern Brazil) is rapidly migrating toward urban areas. To understand the depositional processes (evolution of the dune), a Ground Penetrating Radar (GPR) survey was carried out. The survey is composed by sixteen profiles in E-W direction, which is parallel to the dominant wind direction, and five profiles in N-S direction. In both directions, it was used antennas of 200 MHz and 80 MHz. Additionally, a topographic survey, excavations of two trenches, and grain size analysis were also carried out. The GPR imaged the internal sedimentary structures of the coastal deposits so that it was possible to reconstruct the depositional history of the area. Initially, marine sediments were deposited during the final period of a marine regression of Holocene age. After the exposure of the area, a first phase of aeolian deposition occurred over the marine sediments. Later, a depositional hiatus took place, probably associated with partial erosion of the dune. Finally, a second phase of aeolian deposition occurred, covering all previous strata. Based on the geometry of foresets and bounding surfaces, it was interpreted that, in the second phase of aeolian deposition, the dune changed its morphology from barchan to dome. The morphology change appears to have occurred when the migration front of the dune faced the obstacle constituted by a ramp along in the depositional surface dipping against the wind direction. According to the similarities of the foreset dips in the first and second phases of aeolian deposition, the prevailing dominant winds were very similar to present day dominant winds. So, it is likely that the rapidly migration process of the dune toward urban areas is an entirely natural process. Uma duna localizada próxima às cidades de São Bento do Norte e Caiçara do Norte (litoral nordeste do Rio Grande do Norte, nordeste brasileiro) está migrando rapidamente sobre áreas urbanas. Para entender o processo deposicional (evolução da duna), um levantamento com Radar Penetrante no Solo (GPR) foi realizado. O levantamento é composto por dezesseis perfis na direção E-W, paralelos à direção dos ventos dominantes, e cinco perfis na direção N-S (utilizando antenas de 200 MHz e 80 MHz). Adicionalmente, foram efetuados escavações de duas trincheiras, um levantamento topográfico e análises granulométricas. O GPR imageou as estruturas sedimentares dos depósitos costeiros de modo que foi possível reconstruir a história deposicional da área. Inicialmente, sedimentos marinhos foram depositados durante o período final de uma regressão marinha ocorrida no Holoceno. Após a exposição da área, uma primeira fase de deposição eólica ocorreu sobre os sedimentos marinhos. Mais tarde, ocorreu um hiato deposicional, provavelmente associado com a erosão parcial da duna. Finalmente, ocorreu uma segunda fase de deposição eólica, cobrindo todos os estratos anteriores. Com base na geometria dos foresets e nas superfícies limitantes, foi interpretado que, dentro da segunda fase de deposição eólica, a duna mudou sua morfologia de barcana para dômica. A mudança na morfologia parece ter ocorrido quando a frente de migração da duna encontrou um obstáculo constituído por uma rampa ao longo da superfície deposicional. Devido às semelhanças entre os mergulhos dos foresets dentro da primeira e da segunda fase de deposição eólica, os antigos ventos dominantes foram muito similares aos atuais. Portanto, é provável que o rápido processo de migração da duna em direção a áreas urbanas seja um processo totalmente natural.

The concept of dissipation structures (Bigarella. 1914) refers to processes result introducing morphological, structural and textural modifications imposed to coastal sandy deposits, dunes and beach ridges, during Quaternary global changes. Several structures had been associated to the concept of dissipation structures. although fine textured lenticular contorted structures seems predominant, Twenty-five years later, several doubts persist about the concept. This paper stresses some considerations about de definition of dissipation structures as fine textured lenticular contorted structures ("band of fine") on the basis of the doubts that persist up to nowadays, The main aspects of our analysis deal with: a) the genetic ambiguity of the term: b) the distinction between the different genetic processes: c) the similarity between dissipation structures and pedologic lamellae; d) the generalization of the model associated with the concept. Attention is required when applying the expression dissipation structures to fine textured lenticular contorted structures ("band of fine"). Indeed, this application should be restricted to areas where dissipation processes are well established. In cases other then that, the use of the morphologic expression lamellae is preferable. Also, adjectives may be used to indicate other processes, as iluviation-lamellae for cases when tile accumulation of secondary fine material is verified.

Deposition of washover fans in coastal settings are related to accommodation space, slope of the basin margin, and coeval changes of sea level. Some preliminar y models of development and stacking of sand bodies are presented. [RESUMEN] El depósito de washover fans en áreas costeras está relacionado con el espacio de acomodación disponible, la pendiente del margen de cuenca y los cambios coetáneos de nivel del mar. Se ofrecen modelos preliminares del desarrollo y apilamiento de cuerpos arenosos.

Eustatic movements generate intricate patterns of coastal units. The resulting stratigraphyc architecture depends on eustasy, sediment supply and local tectonics. Tri-dimensional relations due to sea-level changes are interesting because they allow to reconstruct the existence and magnitude of eustatic changes, to understand the role of coastal deposits during the evolution of a basin margin, and to correlate depositional events

Eustatic movements generate intricate patterns of coastal units. The resulting stratigraphyc architecture depends on eustasy sediment supply and local tectonics. Tri-dimensional relatians due to sea-level changes are interesting because they allow to reconstruct the existence and magnitude of eustatic changes, to undersland the rofe of coastal deposits during the evolution of a basin margin, and to correlate depositional events.

Deposition of washo ver fans in coastal settings are related to accommodation space, slope of the basin margin, and coeval changes of sea level. Some preliminary models of development and stacking of sand bodies are presented, El depósito de washover fans en áreas costeras está relacionado con el espacio de acomodación disponible, la pendiente del margen de cuenca y ios cambios coetáneos de nivel del mar. Se ofrecen modelos preliminares del desarrollo y apilamiento de cuerpos arenosos

This paper deals with amino acid racemization ratios and aspartic acid preservation in Holocene (8ka and 2ka old) and today gastropoda, pelecipoda and echinoderma shells from the Gulf of Cadiz. Today samples revealed a relative high aspartic acid racemization process, but there is a net stepwise between the three sampled localities. There is also a fast, time dependent, asparctic acid loss

This paper deals with amino acid racemization ratios and aspartic acid preservation in Holocene (8ka and 2ka old) and today gastropoda, pelecipoda and echinoderma shells from the Gulf of Cadiz. Today samples revealed a relative high aspartic acid racemization process, but there is a net stepwise between the three sampled localities. There is also a fast, time dependent, asparctic acid loss

The Pleistocene deposits exposed in the Amapá Coastal Plain (onshore portion of the Foz do Amazonas Basin, northeastern South America) were previously interpreted as Miocene in age. In this work, they were named as "Itaubal Formation" and were included in the quaternary coastal history of Amazonia. The study, through facies and stratigraphic analyses in combination with optically stimulated luminescence (single and multiple aliquot regeneration), allowed interpreting this unit as Late Pleistocene tidal and fluvial deposits. The Itaubal Formation, which unconformably overlies strongly weathered basement rocks of the Guianas Shield, was subdivided into two progradational units, separated by an unconformity related to sea-level fall, here named as Lower and Upper Units. The Lower Unit yielded ages between 120,600 (± 12,000) and 70,850 (± 6,700) years BP and consists of subtidal flat, tide-influenced meandering stream and floodplain deposits, during highstand conditions. The Upper Unit spans between 69,150 (± 7,200) and 58,150 (± 6,800) years BP and is characterized by braided fluvial deposits incised in the Lower Unit, related to base-level fall; lowstand conditions remained until 23,500 (± 3,000) years BP. The studied region was likely exposed during the Last Glacial Maximum and then during Holocene, covered by tidal deposits influenced by the Amazon River. RESUMODepósitos pleistocenos expostos na Planície Costeira do Amapá (porção onshore da Bacia da Foz do Amazonas, nordeste da América do Sul) foram anteriormente interpretados como de idade miocena. Neste trabalho, esses depósitos foram chamados de "Formação Itaubal" e incluídos na evolução costeira quaternária da Amazônia. O estudo, mediante o uso de análise de fácies e estratigrafia em combinação com luminescência opticamente estimulada (regeneração de alíquotas simples e múltiplas), permitiu posicionar essa unidade no Pleistoceno Tardio, interpretada como depósitos fluviais e influenciados por maré. A Formação Itaubal, que sobrepõe discordantemente rochas intensamente intemperizadas do embasamento do Escudo das Guianas, foi subdivida em Unidade Inferior e Superior, de caráter progradante, separadas por desconformidade relacionada à queda do nível do mar. A Unidade Inferior apresenta idades entre 120.600 (± 12.000) e 70.850 (± 6.700) anos AP e consiste de depósitos de submaré, canal fluvial meandrante influenciado por maré e depósitos de planície de inundação, depositados durante condições de nível de mar alto. A Unidade Superior apresenta idades entre 69.150 (± 7.200) e 58.150 (± 6.800) anos AP e é caracterizada por depósitos de canal entrelaçado, que retrabalham a Unidade Inferior, depositada em condições relacionadas à queda do nível de base. Condições de nível de mar baixo permaneceram até 23.500 (± 3.000) anos AP. A região estudada foi provavelmente exposta durante o Último Máximo Glacial e, posteriormente, durante o Holoceno, recoberta por depósitos influenciados por maré oriundos do Rio Amazonas.

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