The Upper Mississippian Hinton, Princeton, and Bluestone formations of southern West Virginia constitute a wedge of strata that filled the Appalachian basin over a ~7 million year time interval. Seventeen transgressive-regressive sequences comprise the study interval in the basin depocenter. Five sequence types defined by the degree of incision and the thickness/ character of dominant facies include: 1) major incised valley-fill to coastal plain, 2) major incised valley-fill to deltaic, 3) minor incised valley-fill, 4) coastal plain, and 5) marine-dominated sequences. Transgressive and highstand deposits within several sequences contain tidal rhythmites. The prodeltaic Pride Shale member (Bluestone Formation) preserves a hierarchy of submillimeter-to meter-scale cycles that reflect a spectrum of tidal periodicities. The abbreviated character of these microlaminated rhythmites is suggestive of a distal, subtidal setting wherein neap tides were of insufficient strength to transport sand/ silt. Decimeter-scale bundling of semimonthly cycles is ascribed to seasonal fluvial discharge. Meter-scale, multi-year cycles may reflect the 18.6-year lunar nodal cycle. Sequence development likely reflects fourth-order (~400 k.y.), Gondwanan glacioeustatic cycles. The character and relative stratigraphic position of paleoclimatic indicators within the sequences suggests a link between eustasy and patterns of global-scale atmospheric circulation. Calcic vertisols and lacustrine carbonates in coastal plain successions are suggestive of seasonal, semiarid climatic conditions during highstand progradation. Leached paleosols and coals that underlie sequence boundaries and occur within estuarine fills are suggestive of humid conditions during late highstand through early transgression. This pattern may reflect fluctuations in monsoonal circulation whereby the latitudinal shift of seasonal moisture was restricted to the equatorial zone during glaciations. The fourth-order sequences stack into two (2-4 Ma) composite sequences that consist of: 1) a basal retrogradational interval comprised of a major paleovalley-fill sequence overlain by a thick aggradational sequence set made up of fluvial/ coastal plain sequences (TST); 2) a marine interval that demarcates maximum flooding; and 3)(where preserved) a progradational sequence set consisting of minor incised valley-fill sequences (HST). These composite sequences document accommodation change that may reflect global tectono-eustasy. / Ph. D.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Os solos da Chapada do Apodi â CE expressam um grande potencial para uso na agricultura irrigada. SÃo solos fÃrteis quando comparado com outros solos do Brasil, apresentam relevo plano e parte deste possuem grau de drenagem de boa a moderada. No entanto, alguns aspectos sÃo de interesse por parte dos pesquisadores no Ãmbito da CiÃncia do Solo, quanto a sua gÃnese e a presenÃa de nÃdulos nestes solos. Visando aumentar a base de dados à necessÃrio que se faÃa uma caracterizaÃÃo quÃmica e mineralÃgica dos solos e nÃdulos encontrados neste ambiente. Cinco perfis (P1, P2, P3, P4 e P5) de solos encontrados em uma topossequencia desenvolvidos de calcÃrio da formaÃÃo JandaÃra foram estudados. Utilizaramse de anÃlises quÃmicas como o ataque total, ataquesulfÃrico, DCB e difraÃÃo de raios â X para obtenÃÃo de dados para que fosse possÃvel estabelecer relaÃÃes para a compreensÃo da gÃnese dos solos e nÃdulos. Os solos, de maneira geral apresentam teores uniformes de ferro e titÃnio, nÃo sendo notadas grandes diferenÃas entre horizontes e perfis. No entanto, as diferenÃas existentes, destacam o P5 dos de demais perfis, sendo este de maior profundidade, maior teor de ferro e titÃnio, representando um maior grau de intemperismo expresso pela menor relaÃÃo entre os teores de silÃcio e alumÃnio(Ki). A distribuiÃÃo uniforme nos teores de titÃnio em todos os perfis indicam que estes solos foram formados in situ. Os principais minerais encontrados nos solos sÃo caulinita e micaâ ilita. Os nÃdulos apresentaram elevados teores de ferro, no entanto, nÃo foram notadas relaÃÃo inversa entre o teor de ferro e o tamanho das concreÃÃes. Os teores de titÃnio no solo e nas concreÃÃes quando somados e comparados entre perfis apresentaram-se quimicamente semelhantes, evidenciado a formaÃÃo das concreÃÃes in situ. Os principais minerais encontrados nos nÃdulos e concreÃÃes foram caulinita, quartzo, goethita, hematita, anatÃsio e rutilo. A micromorfologia dos nÃdulos e concreÃÃes indicam que as mesmas estÃo em processos de degradaÃÃo. / The soils of the Apodi Plateau - EC express a great potential for use in irrigated agriculture. Fertile soil are compared to other soi l from Brazil, and have flat terrain feature of this degree of drainage good to moderate. However, there is some interest from researchers in the field of Soil Science, as its genesis and the p resence of nodules in these soils. Aiming to increase the database is necessary to make a chemic al and mineralogical characterization of soils and nodules found in this environment. Five p rofiles (P1, P2, P3, P4 and P5) found in a soil toposequence developed from calcareous JandaÃr a were studied. Was used for chemical analyzes as full attack, sulfuric acid, and DCB-ray diffraction X - to obtain data to make it possible to establish relationships for understandi ng the genesis of soils and nodules. The soils generally have uniform levels of iron and titanium, is not noticed big differences between horizons and profiles. However, the differences, P5 differ from those of other profiles, which is of greater depth, more iron and titanium, repres enting a greater degree of weathering expressed by the lower ratio between the contents o f silicon and aluminum (Ki). The concentration of titanium is present in all profile s uniform evidence indicating that these soils were formed in situ. The main minerals found in soil are kaolinite and muscovite - illite. The nodules had high levels of iron, however, there wer e no inverse relationship between the iron content and size of concretions. The titanium conte nt in soil and concretions when summed and compared to profiles showed similar chemically, evidenced the formation of concretions in situ . The main minerals found in nodules and concretion s were kaolinite, quartz, goethite, hematite, anatase and rutile

Les acquisitions de mesures de températures et de conductivités thermiques ont enrichi la connaissance du régime thermique du bassin sédimentaire de Paris et ont mis en évidence des hétérogénéités thermiques spatiales ou temporelles. Afin de mieux les comprendre, ces variations doivent être intégrées dans une vision multidisciplinaire confrontant données et modèles. La revue bibliographique sur le sujet a permis d’intégrer les données de natures diverses, de les confronter par SIG et d’investiguer les connaissances. Cette étude a mis en évidence et réinterprété les variations verticales de flux géothermal. Les simulations conduites à partir de scénarios diffusifs paléoclimatiques montrent que le système a gardé en mémoire l’effet des paléoclimats. Par ailleurs, nous identifions pour la première fois une décroissance systématique du flux géothermal au niveau des principales formations aquifères. Des simulations thermo-hydrauliques transitoires des phénomènes paléoclimatiques mettent en évidence le développement de zones froide et chaude suivant les régions d’écoulement. Une explication de l’anomalie de température de plus de 20°C entre les installations géothermiques situées au nord et au sud de Paris au Bathonien est proposée. Les modélisations effectuées montrent clairement la contribution potentielle de zones fracturées, ainsi que celle des failles, à l’hétérogénéité observée dans le champ de température du bassin en permettant des écoulements contraints par le gradient de charge régional et les instabilités densitaires. Ces travaux ont montré le lien entre les formations du bassin qui sont exploitées pour leurs ressources ou utilisées comme milieu de stockage. / The acquisition of measurements of temperature and of thermal conductivity has enriched the understanding of the thermal regime of the Paris sedimentary basin and brought to light spatial and temporal thermal heterogeneities. In order to understand them better, these variations need to be integrated into a multidisciplinary vision of the basin by comparing data against models. The bibliographic review made it possible to integrate data of diverse sorts, to compare them using GIS and to investigate the knowledge base. This study has highlighted and reinterpreted the vertical variations of geothermal flux. Simulations carried out based on diffusive palaeoclimatic scenarios show that the system has retained a memory of the effects of palaeoclimates. Furthermore, for the first time, a systematic decline of the geothermal flux has been identified at the level of the main aquifer formations. Transitory thermo-hydraulic simulations of palaeoclimatic phenomena show the development in the sedimentary basin of cold and hot zones according to the areas of flow. An explanation of the temperature anomaly of over 20°C between the geothermal installations located to the north and south of Paris in the Bathonian is put forward. The models produced clearly show the potential contribution of fractured zones, as well as that of the faults, to the heterogeneity observed in the temperature field of the basin by allowing flow constrained by the regional charge gradient and unstable densities. This work has shown the link between the formations in the basin which are exploited for their resources or used as a storage medium.

Thesis (MSc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Vaalputs radioactive waste disposal facility is situated in an arid region of Bushmanland currently with evapotranspiration potential that far exceeds precipitation. Dominant soil features in Vaalputs are palimpsests of climates under which they formed. Particle sizes vary drastically between horizons which suggest different modes of sediment transport. Petrographic analyses revealed euhedral habits of primary mineral feldspar within the soils of Vaalputs. This suggests a proximal source of sediments and minimal primary mineral weathering under an arid climate where euhedral grains of feldspar are maintained. The surface horizon of the soils is covered by an equigranular coarse sand of residual aeolian origin. The transition from the surface horizon to the subsurface horizons is widely marked by a pebble sized stone-line. The pebble sized material of the stone-line suggests residual accumulation during the weathering of a previously surface exposed horizon. Since deposition of subsurface sediments (15 Ma) pedogenic alteration has been active in Vaalputs. This has resulted to a complex soil system which displays varied forms of thick dorbank horizons including massive polygonal peds and platy horizons. The polygonal peds are defined by desiccation cracks where vertical and horizontal laminations are hosted. Slaking tests as well as bulk chemistry confirmed that the laminations are composed largely of secondary calcite, however elemental mapping revealed numerous illite bands alternating with calcite layers. It is proposed that calcite layers represent solution features rather than cutanic features. Signs of hydromorphy are commonly observed within the dorbank horizons, since an arid climate currently prevails in Vaalputs such hydromorphic features may indicate formation under past climates. The occurrences of palygorskite, sepiolite and dorbank horizons in Vaalputs require high soil pH (generated by high concentrations of Na) for their formation. Vaalputs soils, however, measured circumneutral pH and relatively low Na concentrations which suggests that palygorskite, sepiolite and dorbank horizons are relic features. Salt casts of lenticular texture occur between polygonal peds of massive dorbank horizons and their enveloping vertical and horizontal laminations. Scanning Electron Microscope analyses indicate high concentrations of Mg, Al, Si and O which suggests sepiolite and palygorskite accumulation through a replacement of gypsum. Elemental maps in conjunction with x-ray tomography and bulk chemical analyses revealed that high concentrations of secondary barite occur along the contact surfaces between dorbank horizons and the laminations. The solution chemistry of all horizons show supersaturation with respect to barite suggesting that the Ba accumulation adjacent to the laminations is likely to have taken place at lower sulphate conditions than those present in the soils today. Evidence shows that Vaalputs soils have experienced at least one climate shift. The preserved soil mottles are indicative of soil environments that remain wet for an extended period. A fine textured platy dorbank horizon is an extensive feature in Vaalputs. The presence of this horizon indicates that the sediments were deposited from a low energy fluvial system. The large polygonal ped units in the lower dorbank units as well as the barite enrichments in pore spaces suggests a climate shift from wet to dry began after the sediments were deposited. / AFRIKAANSE OPSOMMING: Vaalputs radioaktiewe afval fasiliteit is geleë in 'n ariede streek van Namakwaland met evapotranspirasie potensiaal wat neerslag tans ver oorskry. Dominante grond funksies in Vaalputs sluit in 'palimpsests‘ klimaat kondisies waaronder dit gevorm het. Deeltjies groottes wissel drasties tussen horisonne wat op verskillende vorme van sediment vervoer dui. Die oppervlak in Vaalputs word gedek deur 'n gelyke korrelagtige growwe sand van residuele eoliese oorsprong. Die oorgang vanaf die oppervlak horison na die ondergrondse horisonne word algemeen gekenmerk deur 'n spoelsteen grootte kliplyn. Die spoelsteen grootte materiaal van die kliplyn dui op residuele opbou gedurende die verwering van 'n voormalige oppervlak blootgestelde horison. Sedert afsetting van die ondergrondse sedimente (15 Mj) is pedogenetiese veranderinge reeds aktief in Vaalputs. Dit het gelei tot 'n komplekse grond stelsel wat verskillende vorme van dik dorbank horisonne insluitend massiewe veelhoekige pedons en plaatagtige horisonne vertoon. Die veelhoekige pedons word gedefinieer deur uitgedroogde krake waar die vertikale en horisontale lamellering aangetref word. Ontbindingstoetse sowel as heelrots chemiese analiese bevestig dat die lamellering grootliks bestaan uit 'n sekondêre kalsiet. Elementele kartering het egter talle illiet bande afgewissel met kalsiet lae openbaar. Daar word voorgestel dat kalsiet lae verteenwoordigend van oplossingskenmerke is eerder as kuntanise kenmerke. Tekens van hidromorfie word algemeen binne die dorbank horisonne waargeneem, aangesien droë klimaat tans in Vaalputs heers kan sulke hidromorfiese kenmerke dui op die vorming onder vorige klimate. Die groot voorkomste van paligorskiet, sepioliet en dorbank horisonne in Vaalputs vereis hoë grond pH (wat gegenereer word deur hoë konsentrasies van Na) vir hul vorming. Vaalputs grond het egter relatief neutrale pH gemeet en relatief lae Na konsentrasies wat daarop dui dat paligorskiet, sepioliet en dorbank horisonne oorblyfsel kenmerke is. Sout gietforme met lentikulare texture kom voor tussen veelhoekige pedons van massieve dorbank horisonne en hul omhullende vertikale en horisontale lamellerings. SEM analiese toon hoe konsentrasies Mg, Al, Si en O aan wat opbou van sepioliet en paligorskiet deur verplasing van gips voorstel. Petrografiese analiese het euhedraal geaardheid van primere veldspaat mineraal getoon binne die grond van Vaalputs. Dit stel 'n bron van sediment voor en minimale pedogenese in dorre klimaat waar euhedraal korrels veldspate bewaar bly. Elementele kartering tesame met x-straal tomografie en heelrots chemiese analiese het getoon dat hoe konsetrasies sekondere bariet langs die kontak oppervlakke tussen dorbank horisonne en lamellerings voorkom. Die oplossingschemie van alle horisonne toon superversadiging met betrekking tot bariet wat voorstel dat die opbou van Ba langs die lamellerings waarskynlik plaasgevind het by laer sulfaat kondisies eerder as die kondisies wat heedendaags in grond voorkom. Bewyse toon dat Vaalputs grond ten minste een klimaatsverandering ondergaan het. Die gepreserveerde grond vlekke is kenmerkend aan grond omgewings wat vogtig gebly het vir 'n geruime tyd. 'n Fyn getekstuurde plaatagtige dorbank horison is 'n uitgebreide verskynsel in Vaalputs. Die teenwoordiheid van hierdie dorbank toon aan dat sedimente vanuit 'n lae energie fluviale sisteem afgeset het. Die groot veelhoekige pedon eenhede in die laer dorbank eenhede sowel as die bariet verryking in porie spasies stel voor dat 'n klimaatsverandering vanaf vogtig na droog begin het nadat die sediment afgeset het.

Pollen analysis of a sediment core from Lake SP02, Melville Peninsula, Nunavut, Canada provides a ~6300 year record of post-glacial vegetation and climate change. Dominant local and regional taxa identified include Cyperaceae, Ericaceae, Artemisia, Salix, and Oxyria. Fossil pollen assemblages, pollen accumulations rates, and variations in sediment organic matter, indicate a period of optimal Holocene warmth between 5300-3900 yr BP, followed by a prolonged period of Neoglacial cooling, as well as a period of relative warmth between 1300-1000 yr BP, interpreted as evidence for the Medieval Warm Period. Variations in pollen abundances and accumulations during the 20th century suggest a response to recent warming that is unprecedented since deglaciation of the Peninsula. Comparisons of the timing and rates of multi-scale climate variations for Melville Peninsula with adjacent sites reveal a potential late Holocene shift in the boundary separating continental and maritime climate regions in the eastern Canadian Arctic.

Pollen analysis of a sediment core from Lake SP02, Melville Peninsula, Nunavut, Canada provides a ~6300 year record of post-glacial vegetation and climate change. Dominant local and regional taxa identified include Cyperaceae, Ericaceae, Artemisia, Salix, and Oxyria. Fossil pollen assemblages, pollen accumulations rates, and variations in sediment organic matter, indicate a period of optimal Holocene warmth between 5300-3900 yr BP, followed by a prolonged period of Neoglacial cooling, as well as a period of relative warmth between 1300-1000 yr BP, interpreted as evidence for the Medieval Warm Period. Variations in pollen abundances and accumulations during the 20th century suggest a response to recent warming that is unprecedented since deglaciation of the Peninsula. Comparisons of the timing and rates of multi-scale climate variations for Melville Peninsula with adjacent sites reveal a potential late Holocene shift in the boundary separating continental and maritime climate regions in the eastern Canadian Arctic.

Com base em um estudo interdisciplinar, os objetivos deste trabalho foram: estudar a dinâmica da vegetação e do nível relativo marinho e inferir o clima, durante o Holoceno, na região nordeste do estado do Espírito Santo. Para tanto foram analisados: (i) vegetação atual (caracterização botânica e \'delta\'13C e \'delta\'15N); (ii) matéria-orgânica do solo (\'delta\'13C, C elementar e datação 14C); (iii) sedimento lacustre (litologia, C e N elementar, \'delta\'13C e \'delta\'15N, datação 14C da matéria-orgânica, pólen e diatomáceas). Os pontos de amostragem estão localizados na Reserva Natural Vale e na Reserva Biológica de Sooretama, região de predomínio de Floresta Ombrófila Densa das Terras Baixas, com fragmentos de Savana e áreas ocupadas por vegetação pioneira. As principais conclusões foram: (i) o local de estudo não apresentou retração florestal durante o Holoceno; (ii) o clima foi inferido como predominantemente úmido; (iii) a dinâmica da vegetação durante o Holoceno no interior e nas proximidades do vale do Rio Barra Seca foi influenciada pelas flutuações do nível relativo marinho: com a transgressão marinha (há aproximadamente 7700 anos cal. A.P.) iniciou-se o deslocamento da vegetação florestal e a instalação do manguezal; entre aproximadamente 4700 até 3000 anos cal. A.P., o período de maior influência marinha, ocorreu o maior distanciamento do manguezal em relação ao ponto estudado; com a regressão marinha, a colonização do vale por vegetação pioneira ocorreu a partir de, aproximadamente, 2300 anos cal. A.P.; há cerca de 1200 anos cal. A.P. ocorreu a instalação do atual ambiente lacustre com a floresta em seu entorno; (iv) o local atualmente ocupado pela Lagoa do Macuco, no interior do vale do Rio Barra Seca, foi caracterizado por um ambiente estuarino durante o período aproximado de 7700 a 3000 anos cal. A.P / Based on an interdisciplinary study, the objectives of the present work were to study the vegetation and relative sea-level dynamics and to infer the climate during the Holocene, at northeastern region of Espírito Santo State. The materials and respective analyses were: (i) modern vegetation (botanic identification, \'delta\'13C and \'delta\'15N); (ii) soil organic matter (total organic carbon, \'delta\'13C and 14C dating); (iii) lake sediment (lithology, total organic carbon and total nitrogen, \'delta\'13C and \'delta\'15N, 14C dating, pollen and diatoms). The sampling points were located at Vale Natural Reserve and Sooretama Biologic Reserve, region of tropical rainforest vegetation dominance, with savanna fragments and pioneer vegetation patches. The main conclusions were: (i) the forest retreatment was not observed in the study site during the Holocene (ii) the climate was predominantly humid (iii) vegetation dynamics inside the Barra Seca River valley and surroundings were influenced by relative sea-level fluctuations: at ca. 7700 cal. yr B.P., the forest vegetation started its retreatment and the mangrove ecosystem was installed; from ca. 4700 to ca. 3000 cal. yr B.P., the period of higher marine influence, occurred the higher mangrove detachment from the sampling point; with the marine regression, the valley colonization by the pioneer vegetation started at ca. 2300 cal. yr B.P.; at ca. 1200 cal. yr B.P. started the installation of modern lacustrine environment, with the Forest in the surroundings; (iv) the present location of Lagoa do Macuco was characterized by na estuarine environment during the period from ~7700 to ca. 3000 cal. yr B.P

Com base em um estudo interdisciplinar, os objetivos deste trabalho foram: estudar a dinâmica da vegetação e do nível relativo marinho e inferir o clima, durante o Holoceno, na região nordeste do estado do Espírito Santo. Para tanto foram analisados: (i) vegetação atual (caracterização botânica e \'delta\'13C e \'delta\'15N); (ii) matéria-orgânica do solo (\'delta\'13C, C elementar e datação 14C); (iii) sedimento lacustre (litologia, C e N elementar, \'delta\'13C e \'delta\'15N, datação 14C da matéria-orgânica, pólen e diatomáceas). Os pontos de amostragem estão localizados na Reserva Natural Vale e na Reserva Biológica de Sooretama, região de predomínio de Floresta Ombrófila Densa das Terras Baixas, com fragmentos de Savana e áreas ocupadas por vegetação pioneira. As principais conclusões foram: (i) o local de estudo não apresentou retração florestal durante o Holoceno; (ii) o clima foi inferido como predominantemente úmido; (iii) a dinâmica da vegetação durante o Holoceno no interior e nas proximidades do vale do Rio Barra Seca foi influenciada pelas flutuações do nível relativo marinho: com a transgressão marinha (há aproximadamente 7700 anos cal. A.P.) iniciou-se o deslocamento da vegetação florestal e a instalação do manguezal; entre aproximadamente 4700 até 3000 anos cal. A.P., o período de maior influência marinha, ocorreu o maior distanciamento do manguezal em relação ao ponto estudado; com a regressão marinha, a colonização do vale por vegetação pioneira ocorreu a partir de, aproximadamente, 2300 anos cal. A.P.; há cerca de 1200 anos cal. A.P. ocorreu a instalação do atual ambiente lacustre com a floresta em seu entorno; (iv) o local atualmente ocupado pela Lagoa do Macuco, no interior do vale do Rio Barra Seca, foi caracterizado por um ambiente estuarino durante o período aproximado de 7700 a 3000 anos cal. A.P / Based on an interdisciplinary study, the objectives of the present work were to study the vegetation and relative sea-level dynamics and to infer the climate during the Holocene, at northeastern region of Espírito Santo State. The materials and respective analyses were: (i) modern vegetation (botanic identification, \'delta\'13C and \'delta\'15N); (ii) soil organic matter (total organic carbon, \'delta\'13C and 14C dating); (iii) lake sediment (lithology, total organic carbon and total nitrogen, \'delta\'13C and \'delta\'15N, 14C dating, pollen and diatoms). The sampling points were located at Vale Natural Reserve and Sooretama Biologic Reserve, region of tropical rainforest vegetation dominance, with savanna fragments and pioneer vegetation patches. The main conclusions were: (i) the forest retreatment was not observed in the study site during the Holocene (ii) the climate was predominantly humid (iii) vegetation dynamics inside the Barra Seca River valley and surroundings were influenced by relative sea-level fluctuations: at ca. 7700 cal. yr B.P., the forest vegetation started its retreatment and the mangrove ecosystem was installed; from ca. 4700 to ca. 3000 cal. yr B.P., the period of higher marine influence, occurred the higher mangrove detachment from the sampling point; with the marine regression, the valley colonization by the pioneer vegetation started at ca. 2300 cal. yr B.P.; at ca. 1200 cal. yr B.P. started the installation of modern lacustrine environment, with the Forest in the surroundings; (iv) the present location of Lagoa do Macuco was characterized by na estuarine environment during the period from ~7700 to ca. 3000 cal. yr B.P