Thesis--Utrecht. / Cover title. Summary in Dutch. Vita. Includes bibliographical references (p. 177-188).

Thesis (M. Phil.)--University of Hong Kong, 1998. / Includes bibliographical references (leaves 222-238).

Orientador: Alessandro Batezelli / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-25T01:50:06Z (GMT). No. of bitstreams: 1 Pereira_CamilaTavares_M.pdf: 6719830 bytes, checksum: c010edfeb787dd0ffb56ed12b5a56676 (MD5) Previous issue date: 2014 / Resumo: A Formação Marília, que aflora no sudeste do Brasil, é uma sucessão sedimentar caracterizada por estratos sedimentares alternados com paleossolos. As feições pedogenéticas podem ser relacionadas com os fatores climáticos e são utilizadas como ferramenta na interpretação de paleoambientes. Através da descrição macro e microscópica, associada a análise mineralógica e fluorescência de raios-X, foram identificados e caracterizados 20 de perfis de paleossolos da Formação Marília, Maastrichtiano da Bacia Bauru. A intercalação de horizontes C, Ck, Bt, Btk e Gley, possibilitaram a elaboração de um modelo de evolução paleoambiental, onde os dados geoquímicas permitiram tecer considerações paleoclimáticas. As mudanças nos processos de formação destes paleossolos foram impulsionadas principalmente pelas variações de umidade disponível. As estimativas de paleoprecipitação (MAP) obtidas por meio do CIA-K em horizontes Bt e Btk, indicam que a pluviosidade variou de 20-1000 mm/ano. Estas condições climáticas contrastantes resultaram na sobreposição de perfis distintos, sugerindo oscilação entre condições áridas a semiáridas. Estes resultados contribuem para um melhor entendimento paleoambiental do Cretáceo Tardio para a porção sudeste brasileira / Abstract: The Marília Formation is the Maastrichtian sequence of the Bauru Basin and crops out in southeastern Brazil. It is a sedimentary succession characterized by alternating sedimentary strata and paleosols. The pedogenic features can be related to climatic factors and are used as a tool in the interpretation of paleoenvironments. By means of a macro- and microscopic description, associated with mineralogical and x-ray fluorescence analyses, twenty paleosol sections were identified and characterized in the Marília Formation. The characterization of C, Ck, Bt, Btk and Gley horizons and the corresponding geochemical data helped define a paleoenvironmental evolutionary model and make some paleoclimatic considerations. Changes in the processes of formation of these paleosols were mainly triggered by moisture variations. Paleoprecipitation estimates (MAP) obtained by means of CIA-K in Bt and Btk horizons indicate that precipitation varied 20-1000 mm/year. These contrasting climatic conditions caused overlapping of distinct profiles, suggesting oscillation between arid to semi-arid conditions. These results contribute to a better understanding of the Upper Cretaceous paleoenvironment in southeastern Brazil / Mestrado / Geologia e Recursos Naturais / Mestra em Geociências

Orientador: Francisco Sérgio Bernardes Ladeira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-20T22:32:57Z (GMT). No. of bitstreams: 1 Bueno_RobertaMarquezi_M.pdf: 8038871 bytes, checksum: d7a9deb149b8074a8cb315a27706bd4a (MD5) Previous issue date: 2012 / Resumo: O Grupo Urucuia, localizado na porção centro-norte da Bacia Sanfraciscana, abrange os estados do Piauí, Bahia, Maranhão, Goiás, Tocantins e Minas Gerais e é formado por um conjunto de arenitos continentais datados do Cretáceo Superior e depositado sobre embasamento fanerozóico e sobre os Grupos Santa Fé e Areado, ambos também pertencentes à Bacia Sanfranciscana. O Grupo Urucuia é composto pelas Formações Posse e Formação Serra das Araras. A Formação Posse é caracterizada pelo deposito de material arenoso em campos de dunas e fluvial entrelaçado, já a Formação Serra das Araras foi depositada sobre a Formação Posse sendo caracterizada por lençóis de areia e depósito de clastos. Uma vez que a área em que está o Grupo Urucuia permaneceu praticamente na mesma latitude desde a separação de Gondwana, seus registros paleoclimáticos dizem respeito a mudanças climáticas em uma mesma latitude. Os depósitos indicam uma situação desértica que vai se tornando cada vez mais úmida. As mudanças ambientais da área também ficaram registradas nos paleossolos do Grupo Urucuia. Eles foram descritos em um afloramento no estado de Goiás e dois no estado do Tocantins. Foram utilizados procedimentos de descrição macromorfológica, micromorfológica e análise de espectrometria de fluorescência de raios-X com a finalidade de se obter dados relevantes a respeito dos processos atuantes durante o período de formação dos mesmos. O primeiro paleossolo (perfil SD) foi encontrado no município de São Domingos (GO) e marca o contato entre as Formações Posse e Serra das Araras, isto é, um momento de mudança ambiental, de deposição por dunas para deposição por lençóis de areia. Ele apresenta características hidromórficas, marcas de raízes e feições micromorfológicas como pedotúbulos, cutãs e glébulas. O segundo (perfil CV) foi encontrado em um corte de estrada entre Mateiros e Ponte Alta do Tocantins e estratigraficamente está no meio da Formação Serra das Araras. Ele apresenta intercalação de horizontes silicificados com não silicificados e apresenta cutãs, pedotúbulos, glébulas e cristalárias.O terceiro perfil (ES) está localizado na cidade de Mateiros (TO), no topo da Serra do Espírito Santo, que também corresponde ao topo da Formação Serra das Araras. O mesmo está fortemente cimentado por sílica de origem pedológica uma vez que existem feições pedológicas formadas por sílica, como silãs e cristalárias. Além destas estão presentes pedotúbulos e glébulas. A silicificação pedogenética, presente em dois paleossolos descritos indica um ambiente de formação árido a semiárido. De uma forma geral, os paleossolos encontrados são, seguramente, indicadores de condições climáticas extremamente quentes e secas na área do Grupo Urucuia durante o Cretáceo Superior. Localmente são capazes de fornecer dados mais confiáveis a respeito da posição na paisagem, vegetação e movimento de água pelo perfil, evidenciado pela frequência comum de cutãs formados não só por sílica, como também argila / Abstract: The Urucuia Group is located in the north central portion of the Sanfranciscana Basin and covers the states of Piauí, Bahia, Maranhão, Goiás, Tocantins and Minas Gerais. It is formed by a set of continental sandstones that date from the Late Cretaceous and deposited on a Phanerozoic bedrock and over Santa Fe and Posse Groups, both also located on Sanfranciscana Basin. The Urucuia Group consists of Posse and Serra das Araras Formations. The Posse Formation is characterized by deposits of sandy material in dune fields and braided fluvial system. Serra das Araras Formation was deposited on Posse Formation and is characterized by sand sheets and deposit of clasts. Since the area in which the Group is Urucuia is located virtually remained at the same latitude since the breakup of Gondwana, its paleoclimate records are related to climate change at the same latitude. The deposits indicate a desert situation that becomes increasingly wet though time. Environmental changes in the area were also recorded in paleosols of Urucuia Group. They were described in an outcrop in the state of Goias and two in the state of Tocantins. There have been used procedures of macromorphological and micromorphological description and X-ray Fluorescence Spectroscopy analysis with the purpose of obtaining relevant data about acting processes during their formations. The first palaeosol (profile SD) was found in the municipality of São Domingos (GO) and marks the contact between Posse and Serra das Araras Formations. This is, a time of environmental change, from deposits of dunes to deposits by sand sheets.He presents hydromorphic characteristics, root marks and micromorphological features as pedotubes, cutans and glebules. The second one (profile CV) was found in a road cut between Mateiros and Ponte Alta do Tocantins and stratigraphically is in the middle of Serra das Araras Formation. He has silicified horizons intercalated with non-silicified horizons and has cutans, pedotubes, glebules and crystals. The third profile, (ES) is located in Mateiros (TO), at the top of Serra do Espírito Santo, which also corresponds to the top of Serra das Araras Formation. It is strongly cemented with pedological silica and as there are soil features formed by silica such as silans and crystals. There are also pedotubes and glebules. The pedogenetic silicification is present in two paleosols that were described as formed in arid to semi-arid environments. In general, the found paleosols are indicators of an extremely hot and drought weather in the Group Urucuia area during Late Cretaceous. Locally they are able to provide more reliable data about their landscape position, vegetation and water movement in the profile, as evidenced by the common frequency of cutans formed not only by silica, but as well as by clay / Mestrado / Análise Ambiental e Dinâmica Territorial / Mestre em Geografia

Most soils in the Eastern Cape Province, South Africa are shallow and are low in organic matter. Therefore these soils are structurally fragile and highly susceptible to inherent degradative processes like hardsetting. The objective of this study was to determine the effect of cattle manure, scalping and soil wetness on aggregate stability, penetration resistance and early maize growth in hardsetting soils. Glasshouse and field studies were conducted to determine the effect of cattle manure on aggregate stability and penetration resistance of freshly exposed topsoils by scalping at 0, 10 and 20 cm depths. In the glasshouse cattle manure was applied at 0 and 20 Mg/ha and matric suction was kept at ~ 30 and ~ 400 kPa; contrasting high and low soil wetness. Three soils were put in pots and arranged in a randomized complete block 3 2 2 factorial design. The field study was done at the University of Fort Hare research farm and the treatments were arranged in a split-plot complete randomized design with three replications. Scalping treatment was the main plot whilst the quantity of the cattle manure applied was the sub plot. Cattle manure increased mean weight diameter (MWD) by between 48% and 71% under glasshouse and between 18% and 33% under field conditions, depending on the soil wetting rate. Cattle manure reduced MWD when the soil under field condition was subjected to mechanical shaking. Soil penetration resistance decreased linearly, with increasing soil wetness but it rapidly increased with increase in matric suction up to ~200 kPa and thereafter the rate of increase reduced. In the glasshouse, all treatments had no significant effects on shoot dry weight but low matric suction increased root dry weight by 133%. Interaction of cattle manure and low matric suction reduced shoot length by 6%, shoot fresh weight by 25%, root surface area by 36%, root length by 5% and root fresh weight by 29% compared to the control. In contrast, application of cattle manure and high matric suction increased shoot length by 37%, shoot fresh weight by 136%, root surface area by 159%, root length by 94% and root fresh weight by 119%. In the field, cattle manure application increased root length density and shoot dry matter by 26% and 30% respectively. Cattle manure improved the stability of aggregates of the hardsetting soil under rapid or slow water intake conditions experienced during rainfall or irrigation. However, under field conditions cattle manure acted as a deflocculant and decreased the stability of aggregates when mechanical stress was applied. The effectiveness of cattle manure in improving maize growth in hardsetting soils was determined by matric suction.

A soil chronosequence near Cox Bay, on the west coast of Vancouver Island, British Columbia, was investigated and verified. Soils in the sequence are developed in sandy beach deposits, which were found to aggrade toward the ocean at a rate of 0.26 m per year. Dendrochronology and geomorphic evidence established surface ages for seven selected pedons (sites 1 to 7) across these deposits, that ranged from 127 years at site 1 to 550 years at site 7. Soil classification ranged from an Orthic Dystric Brunisol (Typic Udipsamment) to an Orthic Humo-Ferric Podzol (Aquic Haplorthod) in thes sites, respectively. A variety of soil weathering characteristics, identified by wet-chemical, physical and optical techniques, were used to demonstrate that the soils along this transect have developed in a manner which is compatible with the presumed genesis of Podzols (Spodosols). A 0.17% increase in B horizon, oxalate extractable Al and a 0.22 meq/100 g decrease in C horizon, exchangeable Mg along this transect were plotted with site age to exemplify soil weathering chronofunctions. Soxhlet procedures were developed to artificially weather Cox Bay chronosequence soil materials, in the laboratory. Site 1, C3 horizon soil samples were leached with distilled water in soxhlets containing O₂, N₂, CO₂ and air atmospheres. The CO₂-water system clearly produced allitic weathering trends, whereas, a total elemental balance approach and more intense leaching were required to further interpret the weathering characteristies created by the other atmospheres. Problems of sample erosion and leachate contamination indicated a need for alterations in the design of the commercially available soxhlet. Modifications made, by reducing the height (A) or completely removing (B) the soxhlet siphon tube, rectified these problems and showed promise in simulating pedogenic processes. Acetic acid (0.3 M) was used to leach 220 g samples of the site 1, C3 horizon soil in A-modified soxhlets. High (4.3 litres per day) and low (2.2 litres per day) leaching rates produced 13 106 and 4 750 mg of precipitate, respectively, which accumulated in the leachates during an eight week experiment. Rates of removal of elements from the soil samples were in the order of Ca > Mg > Fe > K > Al > Na > Si for the low leaching rate and Ca > K > Mg > Al > Fe > Na > Si for the high leaching rate. These results are compatible with a podzolic weathering process. Acetic acid and both A- and B-modified soxhlets were used to weather chronosequence soil samples over 4, 8, 12, 20 and 24 week periods. Chemical changes in the resultant weathered products were evaluated. Ca and Mg decreases in the samples from both types of soxhlet were plotted against weathering time and statistically-derived, exponential functions were used to explain the resultant curves. The similarity between these laboratory chronofunctions and the field chronofunctions, derived earlier, was noted. Calcium-bound phosphate (PCa) and Ca chronofunctions from both field and soxhlet weathered soils were compared mathematically. By comparing the slopes of statistically-generated equations, both the A- a B-modified soxhlets were calibrated to pedogenic time. B-modified soxhlets closely simulated the chronosequence weathering and produced consistent calibration results. Statistically-based chronofunctions predicted that 100 years of pedogenic weathering of PCa required 7.4 weeks of B-modified soxhlet weathering. This compared well with the 5.5 weeks predicted for a similar loss of Ca. A- and B-modified soxhlets were presented as valuable pedologic tools for simulating soil weathering in the Cox Bay soil chronosequence. / Land and Food Systems, Faculty of / Graduate

No description available.

In this study I observed, described and measured differences in morphological, physical and chemical properties as a function of age on mine soils formed from overburden from the New River formation of the Pennsylvanian system in southern West Virginia. Within each group, we sampled nine separate sites and further categorized each to one of three predominant overburden types as observed in the exposed highwall (either predominantly sandstone or shale or an approximately even mixture of the two). Three “topsoiled” sites were sampled for comparative purposes, along with three contiguous soil series commonly found in the region. The most striking differences attributable to age were depth of profile development and horizonation. Aggregate stability, hydraulic conductivity and soil color also showed significant variance with age. The mine soils were generally more fertile in those elements analyzed than the natural soils, and the A horizons of mine soils and the natural soils contained approximately the same amounts of coarse fragments. Among the mine soils, the 5 year old soils were more fertile than the 2 or 10 year old soils. Ten years was not enough time to cause significant differences in textural classification of these soils. Texture was reflective of the parent material. / Master of Science

The genetic and morphological characteristics of Hagerstown silt loam, Pisgah silt loam and Clarksville cherty silt loam, three southwest Virginia soils which were formed from material weathered from limestone, were studied by means of mechanical and chemical analyses, and field studies or the soil profiles. The soils used in this investigation are all related in a general way, that is, they all occur within the Gray-Brown Podzolic region and are all derivatives of relatively highly carbonated rocks. Samples of all three soils were taken in Russell County, Virginia within the same vicinity. Therefore, the variation in the physical and chemical composition are due to variation in parent rock and relief and not to variations in climate. Chemical analyses of the parent rock showed that the Hagerstown silt loam and Clarksville cherty silt loan were formed from material weathered from a dolomitic limestone, and that the Pisgah silt loan was formed from material weathered from a high grade limestone. Total chemical analyses of the various horizons of the soil profiles showed that the soil forming processes of the three soils studied were podzolic is nature. The parent materials or C horizons of all the soil profiles studied were clays. Hagerstown, which contained approximately 38 percent clay in the A₁ horizon and 75 percent clay in the C horizon, was the heaviest of the three soils studied. Laboratory and field classifications of soil class conflicted in the case of the Hagerstown profile. The ratios of silica to alumina, and silica to iron showed clearly the accumulation of alumina or iron in the lower horizons. The base to alumina ratio showed the thoroughness of the weathering of the three soil profiles. Calculations of the percentages of bases lost during the soil forming processes showed that calcium was lost from the soil to a greater extent than the magnesium. / Master of Science

The Cullen soil series concept in the Virginia Piedmont has been the subject of much debate. This series was originally named Lloyd and was mapped throughout the southeastern Piedmont. In 1969 the Lloyd series was deactivated because of conflicting concepts. The Cullen series was established in 1970 to cover the Lloyd concept in Virginia. This soil is developed from a mixed felsic and mafic parent material and has been mapped over various rock types. A dark red (10R or 2.5YR 3/6) B subhorizon is the major morphologic feature of this soil series. Field and laboratory evaluations were undertaken to: (1) examine the relationship of Cullen and associated soil series and provide a method for their separation, (2) determine if geomorphic or weathering differences exist in Cullen and associated soil series, and (3) determine the classification of the Cullen series in Soil Taxonomy. The majority of Cullen pedons sampled classified as Typic Hapludults, clayey, mixed, thermic, but bordered on the kaolinitic and oxidic mineralogy classes. Chemical and physical properties were consistent in the pedons sampled and did not relate well to parent rock type or B horizon color. Weathering for an extensive time period has brought soils derived from various parent materials to a similar mineralogical state. We recommend that the Cullen series concept be broadened to include red (10R or 2.5YR) soils that have a mixed mineralogy. This concept covers a range between the Davidson and Tatum series and includes what has been mapped as Georgeville in Virginia. / Master of Science