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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Sedimentology and distribution of heavy minerals in the Lower Orange River Valley

Fowler, Jonathan Anthony January 1982 (has links)
No description available.
2

Caracterização e gênese de Espodossolos da planície costeira do Estado de São Paulo / Characterization and genesis of Spodosols on the São Paulo State sandy coastal plain

Coelho, Maurício Rizzato 12 February 2009 (has links)
A gênese, a química, a macro e micromorfologia dos solos desenvolvidos nos ambientes arenosos da planície costeira do Estado de São Paulo foram investigadas. Nesses ambientes, genericamente denominados de restinga, a podzolização é o processo pedogenético predominante, sendo os Espodossolos e Neossolos Quartzarênicos os solos mais comumente encontrados. Os municípios paulistas de Cananéia, Ilha Comprida e Bertioga foram selecionados para o desenvolvimento desta pesquisa devido à presença de diferentes unidades sedimentares, de vegetação remanescente e de solos, representativos da planície costeira do Estado de São Paulo. Nesses locais foram descritos e amostrados 31 perfis, muitos deles em cronosseqüência. A idade dos sedimentos e da matéria orgânica de horizontes cimentados selecionados (ortstein) também foram investigadas e, juntamente às análises químicas, incluindo procedimentos de dissolução seletiva do Fe e Al (DC, oxalato e pirofosfato para Fe e Al; NaOH, KCl, LaCl3 e CuCl2 para Al) e às micromorfológicas, permitiram concluir que: (a) os Espodossolos mais evoluídos e antigos, dotados de horizontes ortstein, podem ser considerados indicadores dos sedimentos pleistocênicos da Formação Cananéia das planícies costeiras quaternárias estudadas e, possivelmente, são paleossolos; (b) o tempo e o relevo foram os principais fatores de formação, condicionantes da diferenciação dos Espodossolos na paisagem; (c) os solos mais antigos, bem drenados devido às condições de relevo e dinâmica sedimentar (Ilha de Cananéia e Bertioga), apresentam grande variabilidade e diversidade de seus horizontes e atributos morfológicos, diferindo daqueles mais jovens e mal drenados, mais homogêneos, geralmente destituídos de horizonte Bs (Bertioga); (d) a química da maioria dos solos estudados são típicas daqueles já descritos para as áreas sob vegetação de restinga: baixas soma e saturação por bases, extremamente a fortemente ácidos, capacidade de troca de cátions dependente da matéria orgânica e saturada com Al trocável, aumento do carbono orgânico em profundidade; (e) o Al é o principal cátion envolvido na podzolização, sendo que suas formas ativas são: complexos de Alhúmus e compostos inorgânicos pouco cristalinos. Os primeiros predominam nos horizontes superficiais e horizontes espódicos hidromórficos; as formas inorgânicas se relacionam a alguns horizontes espódicos (Bs, Bh, Bhs e Bsm) situados na base de perfis bem drenados; (f) Al inorgânico pouco cristalino também foi extraído pelos reagentes pirofosfato e CuCl2, geralmente utilizados para avaliar Al unido à matéria orgânica; ao contrário, LaCl3 extraiu apenas as formas ativas da interação Al-húmus, sendo que KCl não incluiu todas essas formas reativas; (g) a decomposição de raízes in situ e, sobretudo, os processos de formação e transporte de complexos Al-húmus foram observados em alguns (decomposição de raízes) ou em todos os perfis estudados (complexos Al-húmus), originando os horizontes espódicos às expensas dos eluviais; (h) a imobilização desses complexos se dá por diferentes mecanismos: filtragem físicomecânica dos poros do solo, aumento do pH em profundidade, incorporação adicional de Al durante seu transporte e o efeito da absorção seletiva das raízes. Neste último processo, as raízes absorvem seletivamente água e nutrientes, segregando e precipitando ao seu redor os complexos Al-húmus da solução do solo, mobilizados dos horizontes superiores ou presentes nas águas de drenagem. / The genesis, chemistry and macro and micromorphology of soils developed on the sandy coastal plain of the São Paulo State were investigated. In these environments, often designated restinga, podzolization is the main pedogenetic process, being Spodosols and Quartzipsamments the soils most commonly found. Cananéia, Ilha Comprida and Bertioga cities were selected for the development of this research due to the representativeness of this environmental condition in the São Paulo State. In these environments 31 soil profiles were described and sampled, mainly in chronosequences. Age of sediments and of organic matter of cemented horizons (ortstein) were investigated as well. These data associated to the chemical analysis, including Fe and Al selective dissolution procedures (dithionite-citrate, oxalate and pyrophosphate for Fe and Al; NaOH, KCl, LaCl3 and CuCl2 for Al) and micromorphological analysis allowed the following conclusions: (a) the most developed Spodosols have ortstein horizons and can be considered indicators of sediments of Pleistocene age from the Cananéia Formation of the studied quaternary coastal plain and possibly are paleosols; (b) time and relief were the main soil formation factors responsible for differentiation of Spodosols on the landscape; (c) the oldest and well drained soils due to relief conditions and sedimentary dynamics (Cananéia and Bertioga) showed great variability and diversity of their horizons and morphological properties, differing from the youngest, poorly drained and more homogeneous Spodosols usually without Bs horizon (Bertioga). The youngest and well drained Spodosols (Ilha Comprida) showed an advanced degree of degradation; (d) the chemical properties of the studied soils are similar to other soils already described in the restinga: low in exchangeable bases, low in base saturation, strongly acidic, organic-matter dependent and Al-saturated CEC, increase in organic carbon with depth; (e) Al is main metal related to the podzolization process. The reactive forms of this element are Al-humus complexes and inorganic poorly crystalline compounds. Alhumus complexes predominate in the superficial and spodic, poorly drained horizons; the Alinorganic forms occur in some well drained spodic horizons (Bs, Bh, Bhs and Bsm) situated at the bottom of the well-drained soil profiles; (f) Al inorganic, poorly crystalline forms were extracted by pyrophosphate and CuCl2 reagents, usually used to determinate Al bound to organic matter; unlike, LaCl3 only extracted the reactive forms of Al-humus interaction, whereas KCl did not include these reactive forms; (g) Al-humus formation and mobilization were the main pedogenetic processes, but roots decomposition were observed in some horizons; (h) different mechanisms are related to Al-humus complexes immobilization: physical-mechanical filtering effect on soil pores, precipitation as pH increases with depth, precipitation with the decrease of C-to-metal ratio during organic matter complexation and roots selective absorption effect. In the latter, there is selective absorption of water and nutrients with segregation and precipitation of Al-humus complexes around roots. These Al-humus complexes are either mobilized from the superficial horizons or already dissolved in the draining water.
3

Caracterização e gênese de Espodossolos da planície costeira do Estado de São Paulo / Characterization and genesis of Spodosols on the São Paulo State sandy coastal plain

Maurício Rizzato Coelho 12 February 2009 (has links)
A gênese, a química, a macro e micromorfologia dos solos desenvolvidos nos ambientes arenosos da planície costeira do Estado de São Paulo foram investigadas. Nesses ambientes, genericamente denominados de restinga, a podzolização é o processo pedogenético predominante, sendo os Espodossolos e Neossolos Quartzarênicos os solos mais comumente encontrados. Os municípios paulistas de Cananéia, Ilha Comprida e Bertioga foram selecionados para o desenvolvimento desta pesquisa devido à presença de diferentes unidades sedimentares, de vegetação remanescente e de solos, representativos da planície costeira do Estado de São Paulo. Nesses locais foram descritos e amostrados 31 perfis, muitos deles em cronosseqüência. A idade dos sedimentos e da matéria orgânica de horizontes cimentados selecionados (ortstein) também foram investigadas e, juntamente às análises químicas, incluindo procedimentos de dissolução seletiva do Fe e Al (DC, oxalato e pirofosfato para Fe e Al; NaOH, KCl, LaCl3 e CuCl2 para Al) e às micromorfológicas, permitiram concluir que: (a) os Espodossolos mais evoluídos e antigos, dotados de horizontes ortstein, podem ser considerados indicadores dos sedimentos pleistocênicos da Formação Cananéia das planícies costeiras quaternárias estudadas e, possivelmente, são paleossolos; (b) o tempo e o relevo foram os principais fatores de formação, condicionantes da diferenciação dos Espodossolos na paisagem; (c) os solos mais antigos, bem drenados devido às condições de relevo e dinâmica sedimentar (Ilha de Cananéia e Bertioga), apresentam grande variabilidade e diversidade de seus horizontes e atributos morfológicos, diferindo daqueles mais jovens e mal drenados, mais homogêneos, geralmente destituídos de horizonte Bs (Bertioga); (d) a química da maioria dos solos estudados são típicas daqueles já descritos para as áreas sob vegetação de restinga: baixas soma e saturação por bases, extremamente a fortemente ácidos, capacidade de troca de cátions dependente da matéria orgânica e saturada com Al trocável, aumento do carbono orgânico em profundidade; (e) o Al é o principal cátion envolvido na podzolização, sendo que suas formas ativas são: complexos de Alhúmus e compostos inorgânicos pouco cristalinos. Os primeiros predominam nos horizontes superficiais e horizontes espódicos hidromórficos; as formas inorgânicas se relacionam a alguns horizontes espódicos (Bs, Bh, Bhs e Bsm) situados na base de perfis bem drenados; (f) Al inorgânico pouco cristalino também foi extraído pelos reagentes pirofosfato e CuCl2, geralmente utilizados para avaliar Al unido à matéria orgânica; ao contrário, LaCl3 extraiu apenas as formas ativas da interação Al-húmus, sendo que KCl não incluiu todas essas formas reativas; (g) a decomposição de raízes in situ e, sobretudo, os processos de formação e transporte de complexos Al-húmus foram observados em alguns (decomposição de raízes) ou em todos os perfis estudados (complexos Al-húmus), originando os horizontes espódicos às expensas dos eluviais; (h) a imobilização desses complexos se dá por diferentes mecanismos: filtragem físicomecânica dos poros do solo, aumento do pH em profundidade, incorporação adicional de Al durante seu transporte e o efeito da absorção seletiva das raízes. Neste último processo, as raízes absorvem seletivamente água e nutrientes, segregando e precipitando ao seu redor os complexos Al-húmus da solução do solo, mobilizados dos horizontes superiores ou presentes nas águas de drenagem. / The genesis, chemistry and macro and micromorphology of soils developed on the sandy coastal plain of the São Paulo State were investigated. In these environments, often designated restinga, podzolization is the main pedogenetic process, being Spodosols and Quartzipsamments the soils most commonly found. Cananéia, Ilha Comprida and Bertioga cities were selected for the development of this research due to the representativeness of this environmental condition in the São Paulo State. In these environments 31 soil profiles were described and sampled, mainly in chronosequences. Age of sediments and of organic matter of cemented horizons (ortstein) were investigated as well. These data associated to the chemical analysis, including Fe and Al selective dissolution procedures (dithionite-citrate, oxalate and pyrophosphate for Fe and Al; NaOH, KCl, LaCl3 and CuCl2 for Al) and micromorphological analysis allowed the following conclusions: (a) the most developed Spodosols have ortstein horizons and can be considered indicators of sediments of Pleistocene age from the Cananéia Formation of the studied quaternary coastal plain and possibly are paleosols; (b) time and relief were the main soil formation factors responsible for differentiation of Spodosols on the landscape; (c) the oldest and well drained soils due to relief conditions and sedimentary dynamics (Cananéia and Bertioga) showed great variability and diversity of their horizons and morphological properties, differing from the youngest, poorly drained and more homogeneous Spodosols usually without Bs horizon (Bertioga). The youngest and well drained Spodosols (Ilha Comprida) showed an advanced degree of degradation; (d) the chemical properties of the studied soils are similar to other soils already described in the restinga: low in exchangeable bases, low in base saturation, strongly acidic, organic-matter dependent and Al-saturated CEC, increase in organic carbon with depth; (e) Al is main metal related to the podzolization process. The reactive forms of this element are Al-humus complexes and inorganic poorly crystalline compounds. Alhumus complexes predominate in the superficial and spodic, poorly drained horizons; the Alinorganic forms occur in some well drained spodic horizons (Bs, Bh, Bhs and Bsm) situated at the bottom of the well-drained soil profiles; (f) Al inorganic, poorly crystalline forms were extracted by pyrophosphate and CuCl2 reagents, usually used to determinate Al bound to organic matter; unlike, LaCl3 only extracted the reactive forms of Al-humus interaction, whereas KCl did not include these reactive forms; (g) Al-humus formation and mobilization were the main pedogenetic processes, but roots decomposition were observed in some horizons; (h) different mechanisms are related to Al-humus complexes immobilization: physical-mechanical filtering effect on soil pores, precipitation as pH increases with depth, precipitation with the decrease of C-to-metal ratio during organic matter complexation and roots selective absorption effect. In the latter, there is selective absorption of water and nutrients with segregation and precipitation of Al-humus complexes around roots. These Al-humus complexes are either mobilized from the superficial horizons or already dissolved in the draining water.
4

Quaternary marine terraces on Cyprus : constraints on uplift and pedogenesis, and the geoarchaeology of Palaipafos

Zomeni, Zomenia 12 June 2012 (has links)
Numerous flights of Quaternary marine terraces are present around the island of Cyprus, in the Eastern Mediterranean. These terraces are a result of the global eustatic sea-level curve and local tectonism. Marine Isotope Stage (MIS) 5 through MIS 13 terraces are identified, mapped and dated. Palaeoshoreline elevation, an excellent indicator for a past sea–level, and new numerical geochronology are used to calculate an Upper Pleistocene uplift rate for various coastal sectors. Southwestern Cyprus presents the highest uplift rates of 0.35-0.65 mm/year with other sections suggesting uplift of 0.07-0.15 mm/year. This Upper Pleistocene tectonic signal is attributed to an active offshore subduction/collision system to the southwest of Cyprus, evidenced from the seismic activity offshore and the surface expression of a blind thrust fault in the Pafos region. Soil chronosequences and geology in southwestern Cyprus are studied in order to understand the Quaternary development on this uplifting landscape. Soil profile properties are used to calculate a profile development index (PDI), a method often applied to geomorphic surfaces as a relative dating method. Well-developed red and clayey soils occur in the coastal sector, on broad and low-angle surfaces, specifically on marine terraces and alluvial fans. Higher elevations of steep slopes consisting of carbonate and ophiolite lithologies host poorly developed soils. Results show variable PDI's on uplifted terraces, obscured by transported materials, active alluvial fan buildup and hillslope erosion. Calcium carbonate build-up in soil profiles in the form of nodular and laminar accumulations are used as another relative dating method. Geochronology of marine terraces is used as an age range approximation for carbonate stages. Geomorphologic mapping focuses on the southeastern part of the Pafos thrust fault, the only point on the landscape where this otherwise blind fault is exposed on the surface. This is the location of Palaipafos, an important Ancient polity, today the site of the village of Kouklia. Geoarchaeological study suggests little landscape change over the last 4000 years in the vicinity of the urban core of Palaipafos, this being attributed to bedrock and landscape resistance of its location, a plateau at 80 m amsl. Copper deposits in the Palaipafos hinterland had provided a valuable resource at one time. Soil and water resources continue to sustain agriculture.Tectonic uplift in this part of the Pafos thrust fault is estimated to be 2.1mm/year, considered, together with Late Holocene sea-level change responsible for the shifting locations and eventual abandonment of the Palaipafos harbor in the coastal lowlands. / Graduation date: 2013

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