Literatura académica sobre el tema "Sols carbonatés"
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Artículos de revistas sobre el tema "Sols carbonatés"
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Timbal, J. y J. Gelpe. "Croissance juvénile du chêne rouge sur des sols carbonatés à des profondeurs variables". Annales des Sciences Forestières 46, Supplement (1989): 694s—696s. http://dx.doi.org/10.1051/forest:198905art0153.
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Dupla, Jean-Claude, Elisabeth Palix, Guillaume Damblans, Alain Puech, Mathieu Blanc, Christophe Dano, Hussein Mroueh et al. "Le projet ANR SOLCYP+ pour améliorer le dimensionnement des monopieux utilisés comme fondations d’éoliennes marines". Revue Française de Géotechnique, n.º 158 (2019): 4. http://dx.doi.org/10.1051/geotech/2019010.
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La plupart des éoliennes offshore sont fondées sur monopieux. L’augmentation constante de la capacité des turbines et l’insuffisance des procédures évoquées dans les documents normatifs, notamment en ce qui concerne la prise en compte des chargements cycliques, posent des défis pour leur dimensionnement. Dans le cas des sites français, la présence de sols et roches carbonatés, dont le comportement est encore mal connu aujourd’hui, rend la tâche encore plus complexe. Le projet SOLCYP+, lancé en 2017 pour une durée de 3 ans, doit permettre de disposer de nouvelles méthodologies fiables et robustes pour le dimensionnement des monopieux de grand diamètre y compris dans le contexte géotechnique du plateau continental français. Cet article présente une description détaillée du projet ANR SOLCYP+. On aborde, tout d’abord, le contexte, la problématique et les objectifs du projet puis, dans un second temps, on décrit plus en détail les quatre principales tâches scientifiques.
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El Howayek, Alain, Antonio Bobet y Marika Santagata. "Microstructure and cementation of two carbonatic fine-grained soils". Canadian Geotechnical Journal 56, n.º 3 (marzo de 2019): 320–34. http://dx.doi.org/10.1139/cgj-2018-0059.
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This paper presents an investigation of the microstructure and cementation of two carbonatic fine-grained soils obtained from a deposit of lacustrine origin formed during the Wisconsin glaciation. The two soils differ in the degree of cementation (with average total carbonate contents of ∼55% and ∼38%), the dominating carbonate mineral (calcite versus dolomite), and the forms of carbonates present. The study is founded on observations of the microstructure using scanning electron microscopy (SEM) equipped with energy-dispersive X-ray (EDX) spectrometry, and examination of the effects of carbonate dissolution on Atterberg limits and particle-size distribution. In both soils, the majority of the carbonate is in the form of a coating layer on the clay and silt particles, with a thickness less than 2–3 μm, and decreasing in the sample with lower carbonate content. This coating layer “networks” particles and groups of particles. Carbonate cementation impacts the engineering properties of both soils, and the site’s overconsolidation ratio (OCR) profile clearly reflects changes in carbonate content and microstructure. One-dimensional compression tests show that cementation is associated with a moderate degree of structuring, and that the resulting structure is stable, with no complete destructuration occurring even after the effective stress exceeds 10 times the preconsolidation stress.
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Wang, Dunling y Darwin W. Anderson. "Pedogenic carbonate in Chernozemic soils and landscapes of southeastern Saskatchewan". Canadian Journal of Soil Science 80, n.º 2 (1 de mayo de 2000): 251–61. http://dx.doi.org/10.4141/s99-063.
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The objective of this study was to characterize soil carbonates and estimate their accumulation by using a method based on δ13C values of soil carbonate in pedons and landscapes. Dark Brown Chernozem soils of the Amulet Association (with mixed C3 and C4 plants) and native Black Chernozem soils of the Oxbow Association (with a pure C3 plants) were included. Six soil samples representing the Cca and Ck horizons of the Oxbow and Amulet Associations were chosen for detailed pedogenic carbonate studies, which include particle size fractionation, mineralogical identification, surface morphology examination, and stable carbon isotopic compositions analysis on the particle size fractions.X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses of the fractionated particle sizes indicated that dolomite dominates the carbonate occurring in the Ck horizons, and is mainly in medium and coarse silt fractions. In the Cca horizons, carbonate in clay and fine silt fractions is mostly calcite, whereas dolomite dominates the carbonates in medium and coarse silt fractions. Calcitic coatings on the surfaces of both silt and sand particles were observed. Stable carbon isotope ratio (δ13Cvalue) of carbonate was −8‰ in the clay fraction of Cca horizons in which carbonate is dominated by calcite. Carbonate in the fine particle size fractions of the Cca horizons is dominated by calcite and has the most depleted δ13C values, indicating that pedogenic carbonate occurs as calcite and mainly in the fine particle size fractions. In contrast, carbonates from coarse silts of Ck horizons were composed solely of dolomite and had the most enriched δ13C values (−1.1 to −1.4‰), a character of lithogenic carbonate. On a landscape basis, carbonate occurs mainly in the Cca horizons in mid- and upper slope soils as a result of moisture movement and ground water fluxes. Soils in the depressions were more leached and contained small amounts of carbonate, mostly in the 60- to 90-cm depth. Calculations from the δ13C values of soil carbonates indicate that about 50–68% of the carbonate in the Cca horizons of middle slope soils is of pedogenic origin, which is equivalent to a CaCO3 storage of 136–188 kg m−2. In contrast, 5 to 39% (0–36 kg m−2 CaCO3) of carbonate stored in the lower slope soils is of pedogenic origin. Thirty-one to fifty percent of the carbonate (equivalent to 100–134 kg m CaCO3) in upper slope soils is of pedogenic origin. Key words: Carbonate, pedogenic, calcite, dolomite, δ13C value, XRD, SEM, landscape
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MILLER, J. J., D. F. ACTON y R. J. ST. ARNAUD. "THE EFFECT OF GROUNDWATER ON SOIL FORMATION IN A MORAINAL LANDSCAPE IN SASKATCHEWAN". Canadian Journal of Soil Science 65, n.º 2 (1 de mayo de 1985): 293–307. http://dx.doi.org/10.4141/cjss85-033.
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The results of this study indicate the importance of groundwater flow and water table depth on the genesis, characteristics and distribution of soils within a hummocky morainal landscape. Non-saline and non-carbonated soils in upland depressions can be attributed to "depression-focused" recharge by snowmelt and snowmelt runoff in the spring, as evidenced by deep sola and/or eluvial horizons. Non-saline and carbonated soils on lower slopes adjacent to depressions are associated with local discharge and/or lateral flow from the adjacent groundwater mounds under the depressions in spring, as well as upward flow in the summer resulting from water use by phreatophytes such as willows, creating a water table depression around the slough fringes. Saline and carbonated soils at low elevations are associated with shallow and rather stable water tables, and local discharge from surrounding uplands. Soil types on uplands are more dependent on slope position and infiltration than on depth to water table or groundwater flow. Non-saline soils of different profile types occur on mid- and upper slope positions. These areas have a deep water table with mainly recharge or lateral flow occurring in the saturated zone. The infiltration of surface runoff water in upland depressions is the dominant factor influencing the distribution of soluble salts in this hummocky landscape. Key words: Water table, landscape position, recharge, discharge, soluble salts, soil genesis, morphology, carbonate soil
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Kassim, Jabbar K. "Method for Estimation of Calcium Carbonate in Soils from Iraq". International Journal of Environment 1, n.º 1 (30 de agosto de 2013): 9–19. http://dx.doi.org/10.3126/ije.v1i1.8524.
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Attempts have been made to evaluate four methods of quantitative determination of soil carbonates. Calcium carbonates equivalent were determined by the acid neutralization, calcimeter and acetic acid methods. Also, it obtains by the fourth methods when the acid neutralization method is corrected against proton adsorption. The acid neutralization method gave significantly higher estimates of total carbonates and different from each of the others. The calcimeter method gave the lower estimates of CaCO3 equivalent. The results showed that the corrected values of CaCO3 equivalent did not differ significantly from other three methods but the overall mean tended to be higher than the acetic acid and calcimeter methods. It may be concluded that the acetic acid method is simple, can reasonably estimate the carbonate content and requires only a pH meter. It can be used for routine determination of soil carbonate. DOI: http://dx.doi.org/10.3126/ije.v1i1.8524 International Journal of Environment Vol.1(1) 2013: 9-19
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Souza, Renato Ferreira de, Valdemar Faquin, Ruy Carvalho, Paulo Rogério Ferreira Torres y Adélia Aziz Alexandre Pozza. "Atributos químicos de solos influenciados pela substituição do carbonato por silicato de cálcio". Revista Brasileira de Ciência do Solo 32, n.º 4 (agosto de 2008): 1563–72. http://dx.doi.org/10.1590/s0100-06832008000400020.
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A aplicação de silicatos pode promover incrementos na capacidade de troca de cátions, favorecer a disponibilização de ânions, especialmente o H2PO4- (fosfato diácido), elevar o pH, amenizar a toxidez de Al e, de maneira geral, incrementar a disponibilidade de nutrientes para as plantas, apresentando, porém, uma eficiência agronômica inferior em comparação aos carbonatos. Com o objetivo de avaliar o efeito da substituição do carbonato de Ca por silicato de Ca sobre as propriedades químicas dos solos, especialmente em relação à disponibilidade de P, foram realizados quatro experimentos em casa de vegetação, num delineamento inteiramente casualizado, com quatro repetições. Os tratamentos consistiram de cinco níveis de substituição (0, 25, 50, 75 e 100 %) do carbonato de Ca por silicato de Ca, mantendo uma relação estequiométrica Ca:Mg de 4:1 e o mesmo conteúdo de CaO, suficientes para elevar V = 60 %. Os tratamentos foram aplicados em amostras de 4 dm³ de Neossolo Quartzarênico órtico, Latossolo Vermelho-Amarelo textura média, Latossolo Vermelho-Amarelo textura argilosa e Latossolo Vermelho textura muito argilosa, sendo cada solo um experimento. Foram determinados os valores dos atributos químicos dos solos: pH em H2O, P, P remanescente (P-rem), K, Ca, Mg, Si, Al, H + Al, matéria orgânica (MO), Cu, Mn, Zn e B, soma de bases (S), a CTC efetiva (t), a CTC em pH 7,0 (T), a saturação por bases (V) e a saturação por Al (m), os quais foram submetidos à analise de variância e ao ajuste de modelos de regressão simples, considerando os níveis de substituição de CaCO3 por CaSiO3. Verificou-se que a substituição de carbonato por silicato promoveu aumentos significativos nos valores de Si, Al, H + Al e m e redução nos valores de P-rem, pH, S, t e V; já os valores de P Mehlich-1, K, Mg, MO, T, Mn, Cu e B não foram influenciados significativamente. Houve declínio na disponibilidade de Zn somente no solo RQo. A eficácia do silicato de Ca foi inferior à de carbonato de Ca na melhoria das condições químicas do solo.
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Jarnuszewski, Grzegorz. "Some physical properties of mursh developed on limnic limestones in NW Poland". Soil Science Annual 68, n.º 3 (1 de septiembre de 2017): 132–39. http://dx.doi.org/10.1515/ssa-2017-0016.
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AbstractPost-bog soils developed on carbonate sediments are closely related to a young-glacial landscape and postglacial lakes. Drainage of biogenic accumulation area leads to a series of transformations in accumulated formations, including the process of decession. The studies conducted in the years 2009–2012 were focused on post-bog soils near lakes: Strzeszowskie, Sitno and Drawskie in Western Pomerania. The examined soils belong to murshic soils and gleysols (The classification of Polish soils). Mursh horizons contained from 0.2 to 43.3% of carbonate and from 27.2 to 77.6% of non-carbonates fractions (Ncf), and varying amount of organic matter depending on the degree of mineralisation. Specific density of surface horizons was in the range from 1.76 to 2.33 Mg·m−3, and bulk density from 0.28 to 0.68 Mg·m−3. Higher porosity was found in mursh organic soils in comparison to gleysols. The studies showed that the content of carbonate fraction was related with specific density, bulk density, porosity and water capacity. Obtained results of physical and physico-chemical analysis indicate that dewatering depth of post-bog soils developed on limnic limestone are reflected in worsened water retention properties and reduced capillary ascent in the upper layers of carbonate formations of gleysols.
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García-Montero, L. G., I. Valverde-Asenjo, P. Díaz y C. Pascual. "Statistical patterns of carbonates and total organic carbon on soils of Tuber rufum and T. melanosporum (black truffle) brûlés". Soil Research 47, n.º 2 (2009): 206. http://dx.doi.org/10.1071/sr08084.
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The ascocarps of several truffle species, such as Tuber rufum, are harvested in T. melanosporum brûlés; these species reduce T. melanosporum production. Some authors argue that this competition might be due to the evolution of organic matter in the soil. However, soil conditions in brûlés have yet to be clarified, and most studies on T. melanosporum fail to supply statistical data. We propose a study of 40 soils to compare the values for total organic carbon (TOC), pH, and carbonates inside the brûlés with the values for the outer edges of the same brûlés, where T. rufum ascocarps are collected. A principal component analysis relates the soils from the inner brûlés with high active carbonate content and soils outside the brûlés with high TOC and total carbonate content. ANOVA analyses indicate that the mean concentration of active carbonate, total CO32–, and % active/total carbonate differ significantly depending on soil location, but there are no significant differences for pH and TOC. These results lead us to propose a new hypothesis: T. melanosporum mycelia may solubilise active carbonate (<50 μm) and the other carbonate fractions (>50 μm) inside the brûlés; however the environmental conditions of the brûlés could favour a secondary carbonate precipitation with a net increase in active carbonate. This increase would counterbalance carbonate losses from leaching, which would in turn favour T. melanosporum mycelia, suggesting a feedback process.
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Gordienko, O. A. y E. A. Ivantsova. "Morphological features of the soil cover of slope lands in the south of the Volga uplands within the urban landscapes of Volgograd". Dokuchaev Soil Bulletin, n.º 106 (27 de marzo de 2021): 77–104. http://dx.doi.org/10.19047/0136-1694-2021-106-77-104.
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The paper deals with morphological properties of agrogenically transformed chestnut soils of slope lands in the south of the Volga upland within the urban landscape of Volgograd. It is established that as a result of agrogenesis, erosion, land use change, as well as of agroforestry reclamation measures performed, both anthropogenic deeply transformed and postagrogenic soils have been formed. The greatest changes under the influence of agrogenesis are noted in morphological structure of profiles. Agrogenesis results in degradation of soils involved in active agricultural use due to intensified sheet and rill erosion. In eroded soils there is noticed a decrease in the thickness of agrohumic layer, formation of furrow bottom compaction and changes in structure. Their characteristic feature is the presence on the surface of a homogeneous agro-abraded horizon with lumpy structure, in the lower part of which secondary carbonates inherited from the carbonate horizon and resulted from deep plowing may occur. Soils slightly exposed and not exposed to erosion processes have an agrohumus horizon on the surface, which depending on soil tillage can have thickness from 19 to 36 cm. At present, the annual agricultural practices at the plot include mowing of weeds and disk plowing to 20 cm depth. Earlier moldboard plowing to 40 cm depth was performed. All agrogenically-modified soils are characterized by HCl reaction with carbonates from the surface. Carbonate accumulations in agrogenic soils, as a rule, have a segregated form that indicates rapid summer drying of the profile and short period of soil solutions migration. Upper boundary of accumulative-carbonate horizons of agrogenic soils on the average is at 42 cm depth. Such occurrence of carbonate horizons in general is typical both of natural non-eroded soils of dry-steppe zone and of soils involved in agricultural land use. Under forest plantations the original chestnut soils were transformed into turbated agrozems due to deep ameliorative cultivation preceded planting of woody and shrub vegetation. Soil preparation practices applied before tree species planting resulted in transformation of original chestnut soils into turbated agrozems, which is due to deep (up to 60 cm) soil reclamation. The forest belt, being a “barrier” between the field parts, contributed to the formation of a stratified small horizon (trait) of 10 cm thickness for more than 70 years due to the constant inflow of fine-grained soil and decay of leaf and herbaceous debris.
Tesis sobre el tema "Sols carbonatés"
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Metzger, Laure. "Comportement du rimsulfuron dans deux sols carbonatés". Nancy 1, 1997. http://www.theses.fr/1997NAN10302.
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Le devenir de l'herbicide rimsulfuron dans une rendzine et un sol alluvial a été étudié à partir d'incubations de sols et d'expériences en "batch". L'apport de rimsulfuron, à 4-5 fois les doses recommandées au champ, n'a pas modifié l'activité microbienne des sols, mesurée par la respiration. La minéralisation du rimsulfuron n'a été observée qu'en présence d'une microflore active et était très faible : respectivement 2 et 0,75 % de la radioactivité apportée au sol alluvial et à la rendzine. La plus faible minéralisation du rimsulfuron obtenue avec la rendzine pourrait résulter de la présence de quantités élevées de matière organique qui (i) constituerait une source de carbone alternative pour la microflore et (ii) fixerait des résidus du rimsulfuron, diminuant ainsi leur biodisponibilité. En effet, les études d'adsorption du rimsulfuron montraient non seulement que la surface spécifique influençait l'adsorption, mais que la vitesse d'adsorption semblait augmenter avec la teneur en argiles et la capacité d'adsorption augmentait avec la teneur en matière organique. De plus, des résidus non-extractibles (RNE) de rimsulfuron étaient plus concentrés dans les fractions granulométriques ayant les plus fortes teneurs en matière organique et une part de ces RNE était extractible avec les composés organiques alcalino-solubles. Cependant, 65 à 80 % des résidus du rimsulfuron étaient encore extractibles, même après 3 à 7 mois d'incubation. Cette mobilité potentielle des résidus du rimsulfuron était confirmée par les valeurs des Kd obtenues lors des expériences d'adsorption. Ainsi, des résidus du rimsulfuron peuvent persister dans le sol et être disponibles pour migrer vers les eaux souterraines ou être absorbés par les plantes. Les processus influençant le devenir du rimsulfuron dans les sols sont similaires à ceux qui affectent l'évolution des matières organiques naturelles, mais l'importance relative de ceux-ci et leur durée diffèrentThe fate of rimsulfuron, a sulfonylurea herbicide, was studied in a rendzina and an alluvial soil, through (i) laboratory soil incubations and (fi) batch experiments to de termine the capacity and the dynamics of rimsulfuron adsorption. The application of rimsulfuron, at 4-5 times the recommended field doses, did not modify the soil microbial activity, measured by the soil respiration. The mineralization of rimsulfuron occured only in the presence of an active microflora and was very low: 2 and 0. 75 % of the applied radioactivity for the alluvial soil and the rendzina soil, respectively. The lower rimsulfuron mineralization observed in the rendzina could be explained by high amounts of organic matter that (i) constituted an alternative source of organic carbon for the microflora, and (ii) might increase the adsorption of rimsulfuron residues, thus reducing their availability for mineralization processes. Lndeed, adsorption studies showed not only that the specific surface area influenced the rimsulfuron adsorption, but also that higher clay contents seemed to enhance the adsorption dynamics and that organic matter seemed to increase the adsorption capacity. Besides, non extractable residues (NER) of rimsulfuron were more concentrated in the grain-size fractions having the higher organic matter contents and a non negligible proportion of these NER has been co-extracted with alcalino-soluble organic compounds. However, 65 to 80 % of rimsulfuron residues were still extractable, even after 3 to 7 months. This potential mobility of rimsulfuron residues was confirmed by the Kd values obtained from the adsorption experiments, ranging from 0. 12 to 1. 7. Thus rimsulfuron residues can accumulate in soil and be available for migration or for absorption by plants. The processes influencing the behavior of rimsulfuron in soil are similar to those affecting the evolution of natural organic matter but the relative importance of these processes and their kinetics are different
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Achour, Yosra. "Etude de la mobilité des métaux (Pb, Zn, Cd) et des métalloïdes (As, Sb) dans les sols carbonatés contaminés par les rejets miniers". Electronic Thesis or Diss., Orléans, 2022. https://theses.univ-orleans.fr/prive/accesESR/2022ORLE1041_va.pdf.
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Cette thèse porte sur plusieurs réponses sur l'écodynamisme et la phytodisponibilité des éléments potentiellement toxiques (EPT) dans des sols agricoles fortement contaminés par des rejets miniers développés sur un substrat carbonatés de la Tunisie septentrionale (Jebel Ressas (JRS), Jebel Hallouf (JH1) et Sidi Bouaoune (SB) dans un climat semi-aride. Les principaux contaminants en cause sont Zn, Pb, Cd, As et Sb pouvant atteindre respectivement 185037 mg.kg-1 à JRS, 28 000 mg.kg-1 à (JH1), 1021 mg.kg-1 à JRS, 1 355 mg.kg-1 et 338 mg.kg-1 à (JH1).Ces sols sont essentiellement formés d'argiles (kaolinite, illite, et montmorillonite), de carbonates (calcite, dolomite et hydrozincite), de silicates (quartz et hémimorphite), et de sulfates (barytine et anglésite). L'effet rhizosphérique sur la mobilité des EPT a été étudié par un test cinétique avec des acides à faible poids moléculaire (LMWAOs). Les résultats ont montré une augmentation du pH de la solution initiale (2,8) jusqu'à des valeurs proches de la neutralité, résultant de la dissolution des carbonates. Nos résultats suggèrent que les éléments les plus extractibles sont le Cd et le Zn et dans une moindre mesure le Pb. La mobilité des métalloïdes (As et Sb), était relativement faible à l'exception des sols de Jebel Hallouf et Sidi Bouaouane, ou un pourcentage d'extraction ne dépassant pas 1% pour Sb et 0,1% pour As, respectivement a été observé.Pour la détermination des formes des EPT dans les sols, deux méthodes d'extractions séquentielles ont été appliquées (BCR et Maiz). En parallèle, la concentration totale dissoute dans les eaux porales, la fraction labile (sondes DGT) et l'absorption par les plantes (orge et petit pois) ont été déterminées afin d'étudier la spéciation, la mobilité et la phytodisponibilité de sols agricoles autour de deux sites post-minier (Jebel Hallouf - Sidi Bouaouane et Jebel Ressas). Nos résultats ont montré que les fractions mobile et mobilisable (schéma de Maiz) des sols sont faibles par rapport à leurs concentrations totales. Le schéma de BCR a quant lui révélé que la majeure partie des EPT est liée à la fraction résiduelle à l'exception du Zn à JRS qui est beaucoup plus concentré dans la fraction échangeable. Une exception a été observée aussi pour le Pb dans les sols de Jebel Hallouf où il est distribué de façon similaire dans les fractions échangeable, oxydable et résiduelle dont le pourcentage varie entre 23 % et 32 %. La réponse des plantes vis-à-vis de ces contaminants montre que le petit pois et l'orge ont accumulés des teneurs en EPT dépassant les teneurs absorbées par les plantes dans les sols témoins. Les concentrations des EPT dans les eaux interstitielles ainsi que celles mesurées par DGT ne montrent pas de corrélation avec le contenu foliaire des plantes. Ce résultat s'explique par le fait que les concentrations des EPT accumulées dans les plantes sont supérieurs à celles disponibles dans les eaux interstitielles et que le réapprovisionnement de la phase solide est pratiquement négligeable. Le risque de transfert des EPT vers l'eau souterraine a été étudié par percolation en condition saturée dans des colonnes de sol reproduisant le profil de surface. Une diminution progressive du potentiel redox liée à la concentration en carbone organique dans le sol a induit un accroissement de la mobilité de l'arsenic probablement liée à la réduction microbienne des oxydes de ferThis thesis provides answers on the ecodynamics and phytoavailability of potentially toxic elements (PTE) in agricultural soils heavily contaminated by mining waste developed on a carbonated bedrock of northern Tunisia (Jebel Ressas (JRS), Jebel Hallouf (JH1) and Sidi Bouaoune (SB) in a semi-arid climate.The main contaminants in question are Zn, Pb, Cd, As and Sb which can respectively reach 185037 mg.kg-1 at JRS, 28,000 mg.kg-1 at (JH1), 1021 mg.kg-1 at JRS, 1,355 mg.kg-1 and 338 mg.kg-1 at (JH1).These soils are essentially made up of clays (kaolinite, illite, and montmorillonite), carbonates (calcite, dolomite, and hydrozincite), silicates (quartz and hemimorphite), and sulfates (barite and anglesite).The rhizospheric effect on the mobility of PTE has been investigated using kinetic test with a mixture of low molecular weight organic acids. The results showed an increase in the pH of the solution (initial pH 2.8) up to near neutrality, leading to the dissolution of carbonates. Our results suggest that the most extractable elements are Cd and Zn and to a lesser extent Pb. an extraction percentage not exceeding 1% for Sb and 0.1% for As, respectively, was observed. for metalloids (As and Sb) their extractibility was relatively low with the exception of the soils of Jebel Hallouf and Sidi Bouaouane, with an extraction percentage not exceeding 1% for Sb and 0.1% for As, respectively.For the determination of the forms of the PTE in soils, two methods of sequential extractions were applied (BCR and Maiz). Jointly, the total dissolved concentration in pore waters, the labile fraction (DGT probes) and the absorption by plants (barley and peas) were measured in order to study the speciation, mobility and phytoavailability of two sites post-mining (Jebel Hallouf - Sidi Bouaouane and Jebel Ressas).Our résultats showed that the PTE in the mobile and mobilisable fraction(Maiz scheme) of the soils are low compared to their total concentrations. The BCR scheme revealed that most of the PTE are bound to the residual fraction with the exception of Zn at JRS which is much more concentrated in the exchangeable fraction. An exception was also observed for Pb in JH(1) and JH(2) soils where it was distributed evenly in the exchangeable, oxidizable and residual fractions, the percentage of which varies between 23 % and 32 %.The response of plants to these contaminants shows that peas and barley have accumulated TPE levels exceeding the levels absorbed by plants in control soils.Total dissolved concentrations soil power water as well as concentrations measured by DGT are not correlated with primary plant leaf content. This result is explained by the fact that the concentrations of PTE accumulated in the plants are higher than those available in the power waters and that the replenishment of the solid phase is practically negligible.The risk of transfer of PTE to water was studied by percolation in saturated conditions in soil columns reproducing the surface profile. A progressive decrease in the redox potential related to the concentration of organic carbon in the soil induced an increase in the mobility of arsenic probably related to the microbial reduction of iron oxides
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Santerre, Yannick. "Influence de la diagenèse précoce et de la dynamique sédimentaire sur la distribution des propriétés pétrophysiques dans les réservoirs carbonatés". Aix-Marseille 1, 2010. http://www.theses.fr/2010AIX11042.
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Prédire la distribution des propriétés pétrophysiques au sein des plates-formes carbonatées est un enjeu majeur de l'industrie pétrolière car celles-ci représentent plus de la moitié des réserves en hydrocarbures. Pour résoudre ce problème, des modélisations basées processus à grande échelle permettant de déterminer l'architecture sédimentaire des platesformes sont de plus en plus utilisées. Ces modèles prennent en compte de nombreux paramètres (tectonique, eustatisme, hydrodynamisme, sédimentation) mais la diagenèse précoce n'y est généralement que peu ou pas intégrée. Les processus diagénétiques précoces sont pourtant un facteur de contrôle critique des propriétés pétrophysiques dans les platesformes carbonatées. Afin de mieux déterminer l'influence de la diagenèse précoce et de la dynamique sédimentaire sur la distribution des propriétés pétrophysiques dans les systèmes carbonatés, une étude pluridisciplinaire (sédimentologie, diagenèse et pétrophysique) a été menée dans cette thèse sur une série de plate-forme mixte carbonatée-silicoclastique relativement récente, et qui a été très peu enfouie : la série oligo-aquitanienne de Carry-le-Rouet (nord-ouest de la ville de Marseille, France). Cette étude a permis de montrer que cette série a subi de très importantes modifications diagénétiques précoces. Les transformations minéralogiques observées se sont toutes déroulées au cours des phases d'émersion de la plate-forme, qui ont engendrées la circulation de fluides météoriques à travers les sédiments. Les zones météoriques vadoses mises en place au cours de ces périodes d'émersion ont pu être subdivisées en une sous-zone "sommitale", qui présente un néomorphisme très important des éléments de minéralogies instables et/ou une microsparitisation des matrices, et en une sous-zone "non sommitale", qui présente un gradient de néomorphisme et de cimentation des porosités en fonction de la distance à la surface d'émersion. Les zones météoriques phréatiques présentent quant à elles une dissolution très importante de l'ensemble des minéralogies carbonatées instables. L'étude de la série oligo-aquitanienne de Carry-le-Rouet a permis d'aboutir à une relation entre l'évolution des propriétés pétrophysiques des sédiments (porosité, perméabilité), la dynamique sédimentaire et les processus diagénétiques précoces. Un modèle conceptuel d'évolution des propriétés pétrophysiques pour des sédiments boueux soumis à des conditions climatiques humides en contexte de mer aragonitique a pu être proposé à l'issu de cette thèse. Au premier ordre, ce modèle montre que les propriétés pétrophysiques des sédiments peuvent être estimées à partir de la quantité originelle en éléments de minéralogies instables, de la position au sein des différentes zones diagénétiques, et du temps de résidence dans ces zones (durée d'émersion des plates-formes).
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Deville, de Periere Matthieu. "Origine sédimento-diagénétique de réservoirs carbonatés microporeux : exemple de la formation Mishrif (Cénomanien) du Moyen-Orient". Thesis, Dijon, 2011. http://www.theses.fr/2011DIJOS107/document.
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La microporosité représente jusqu'à 95% de la porosité totale des réservoirs à hydrocarbures et des aquifères dans les calcaires crétacés du Moyen-Orient. Dans ces sédiments microporeux, la porosité est modérée à excellente (jusqu'à 35%), tandis que la perméabilité est faible à modérée (jusqu'à 190mD). A l'inverse, mes faciès microporeux peuvent former des niveaux denses, avec de très faibles porosité et perméabilité (respectivement 2–8% et 0,01–2mD). Dans ce travail, les échantillons proviennent essentiellement de la Formation Mishrif (Cénomanien), mais aussi de la Formation Habshan (Berriasien/Valanginien), afin d'examiner les grandes différences verticales et latérales des propriétés pétrophysiques. Le MEB a été utilisé pour étudier deux contrôles potentiels des qualités réservoir : (1) la morphologie des particules micritiques (forme et contacts intercristallins), et (2) la cristallométrie des micrites, définie comme la taille médiane des particules mesurées sur les clichés MEB. Les données morphométriques ont été comparées avec trois paramètres pétrophysiques (porosité, perméabilité, distribution des rayons de seuil de pore). Les résultats montrent que les matrices micritiques peuvent être subdivisées en trois classes pétrophysiques. La Classe C (micrites strictement microporeuses avec des cristaux grossiers ayant des contacts punctiques à partiellement coalescents) est composée de particules grossières (>2µm), polyhédrales à arrondies. Elle présente des porosités bonnes à excellentes (8-28%), des perméabilités faibles à modérées (0,2-190mD), et des rayons de seuils de pores (PTR) moyens supérieurs à 0,5µm. Cette Classe C est généralement observée dans les shoals bioclastiques riches en rudistes, où de nombreux facteurs sédimentaires (hydrodynamisme…) peuvent défavoriser le dépôt des particules les plus fines. L'étude diagénétique montre que ces micrites grossières peuvent aussi être expliquées par une dissolution précoce des fines particules d'aragonite et de HMC dans des fluides météoriques oxydants, permettant la formation in-situ de surcroissances sur les particules de LMC au sommet de la nappe phréatique météorique. Ces processus induisent une augmentation de la taille des particules micritiques, une lithification précoce de la boue carbonatée, et donc une stabilisation minéralogique précoce des micrites grossières de la Classe C. La Classe F (micrites strictement microporeuses avec des cristaux fins ayant des contacts punctiques à partiellement coalescents, est composée de particules fines (<2µm), polyhédrales à arrondies. Elle présente des porosités bonnes à excellentes (3-35%), mais des valeurs de perméabilité souvent inférieures à 10mD, et des PTR inférieurs à 0,5µm. Cette Classe F est souvent observée dans les sédiments déposés en domaine de plate-forme interne boueuse. La formation de ces micrites fines est aussi expliquée par une stabilisation minéralogique précoce des particules micritiques dans des eaux météoriques confinées, favorisant les processus de néomorphisme, pouvant continuer au cours de l'enfouissement. Plus tard, au cours de l'enfouissement de la série, les qualités réservoirs des Classes C et F sont localement améliorées par de la dissolution mésogénétique (probablement liée à des acides organiques) affectant la matrice micritique durant la mise en charge des réservoirs. La Classe D est formée par des matrices micritiques denses, composées de cristaux anhédraux ou subhédraux avec des contacts fusionnés. Elle présente de très faibles données de porosité et de perméabilité. Ces micrites sont uniquement observées dans les niveaux de plate-forme interne et forment des intervalles inter-réservoirs, généralement en association avec des stylolites et un contenu argileux important, pouvant dépasser 10%. Quelque soit leur mode de formation, ces trois classes peuvent être incorporées dans les futures études de rock-typing portant sur les réservoirs carbonatés microporeux du Moyen-OrientMicroporosity may account for as much as 95% of the total porosity of hydrocarbon and water reservoirs in Cretaceous limestones of the Arabian Gulf. In these microporous facies porosity is moderate to excellent (up to 35%) while permeability is poor to moderate (up to 190mD). Conversely, microporous facies may form dense inter-reservoir or cap rock layers with very low porosity and permeability values (2–8% and 0.01–2mD, respectively). For this study, samples were mainly collected from the Cenomanian Mishrif Formation, but also from the Berriasian-Valanginian Habshan Formation, so as to examine the wide vertical and lateral discrepancies in their petrophysical parameters. Scanning Electron Microscopy was used to investigate two potential controls of reservoir properties: (1) micrite particle morphology (shape and inter-crystal contacts); and (2) micrite crystallometry, defined as the median size of micrite particles measured on SEM photomicrographs. The morphometric data are compared with three petrophysical parameters (porosity, permeability and pore threshold radius distribution). Results reveal that micrite matrixes can be subdivided into three petrophysical classes each with its own distinctive crystallometry, morphology and reservoir properties. Class C (strictly microporous limestones with coarse punctic-to-partially coalescent micrites) is made up of coarse (>2µm) polyhedral to rounded micritic crystals, it has good to excellent porosity (8–28%), poor to moderate permeability (0.2–190mD) and a mean pore threshold radius of more than 0.5µm. The class C is usually observed in rudist-rich bioclastic shoal facies where several sedimentary factors (hydrodynamism, bioproduction …) would disfavour deposition of the finer micritic crystals. Diagenetic study shows that the development of coarse micrites (Class C) must also be explained by the early dissolution of fine aragonite and high magnesium calcite particles in oxygenated meteoric fluids leading to a simultaneous in-situ overgrowth on LMC particles at the top of the meteoric phreatic lens. These processes induce an increase of the crystallometry of micritic particles, an early lithification of the carbonate mud, and so the mineralogical stabilization of coarse Class C micrites. Class F (strictly microporous limestones with fine punctic-to-partially coalescent micrites) is composed of fine (<2µm) polyhedral to rounded micrites with poor to excellent porosity (3–35%), but permeability values of less than 10mD and a mean pore threshold radius of less than 0.5µm. It is mostly observed in sediments deposited in a low energy muddy inner platform setting. The formation of fine micrites (Class F) is also explained by an early mineralogical stabilization of micritic particles in confined meteoric waters, favoring neomorphism processes, which may proceeds during burial. Later, during burial, reservoir properties of classes C and D strictly microporous samples where locally enhanced by mesogenetic dissolution (probably due to organic acids) affecting the microporous matrix during the oil emplacement. Class D (strictly microporous mud-dominated facies with compact anhedral to fused dense micrites) comprises subhedral to anhedral crystals with sutured to fused contacts forming a dense matrix. It has very low porosity and permeability. Class D is only found in low energy muddy inner platform facies and forms inter-reservoir or caps rock layers usually in association with stylolites and clay contents that exceed 10%. Regardless of how they formed, though, the three classes can be usefully incorporated into future rock-typing of the microporous carbonate reservoirs of the Middle East
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Hanich, Lahoucine. "Les traçages d'essai en aquifère hétérogène : méthodes, intérêt et limites : application au milieu alluvionnaire languedocien et comparaison avec les milieux carbonatés et fissurés du nord de la france". Lille 1, 1991. http://www.theses.fr/1991LIL10157.
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L'objectif de ce travail est l'application des traçages d'essai pour l'étude des transferts de soluté dans un aquifère hétérogène. Trois types de traçage ont été réalisés (en écoulement naturel, radial convergent et en puits unique) sur le site expérimental de Marsillargues (Hérault). Ce site est implanté dans l'aquifère alluvionnaire «villafranchien» dont la nappe est semi-captive. Il est muni d'un puits de pompage, de neufs piézomètres satellites, arrivant dans la nappe et de cinq piézomètres superficielles. Les courbes expérimentales de restitution obtenues, pour des traceurs, des distances et des directions d'investigation différentes, montrent que le transfert des traceurs s'effectue selon des chemins préférentiels d'écoulement, essentiellement par convection. Ces essais ont confirmé le rôle primordial des hétérogénéités de l'aquifère dans le transfert de masse. Dans les formations carbonatées du Nord de la France, deux types de traçage (en écoulement naturel et en radial convergent) ont été effectués sur trois sites différents (Escalles, Sangatte et Moranrieux). Ces essais ont montré une étroite relation entre les directions morphologiques, la fracturation du réservoir aquifère et les directions principales d'écoulement souterrain. L'expérimentation réalisée à Escalles a permis de mettre en évidence, pour la première fois dans l'aquifère crayeux du Nord-Pas-de-Calais, l'existence d'un écoulement de type karstique; confirmé par des observations en carrière souterraines. Sur le plan méthodologique, c'est la technique de traçage en puits unique qui fournit les meilleures résultats. La fiabilité de cette technique permet de mieux cerner la variabilité des caractéristiques hydrodispersives des aquifères hétérogènes
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Bruna, Pierre-olivier. "Evolution des propriétés réservoir des carbonates peu poreux : exemple des calcaires du Crétacé Inférieur de la Moyenne Durance". Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4745.
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Les calcaires hémipélagiques du Sud-Est de la France sont caractérisés par de faibles valeurs de porosité et de perméabilité. Ces caractéristiques permettent de considérer ces roches comme de potentiels analogues des réservoirs pétroliers non-conventionnels ou des aquifères fissurés. Ces réservoirs sont d’une importance capitale dans le contexte économique actuel. Néanmoins, l’exploitation de ce type de réservoir représente des risques industriels et des challenges techniques qui doivent être gérés pour réduire leur empreinte sur l’environnement.Ce travail apporte une quantité significative de nouvelles données et des méthodes pour caractériser les réservoirs carbonatés non-conventionnels. Il démontre l’importance des figures de compaction (stylolites, microstylolites et faisceaux de pression-dissolution) sur la capacité de stockage des fluides dans ce type de réservoir. Il montre aussi que l’évolution diagénétique des sédiments carbonatés hémipélagiques dépend de processus précoces (cimentations précoces, compaction différentielle) et éventuellement de réactivations plus tardives (inversion de contraintes tectoniques). Le couplage des modèles 3D avec les géostatistiques apparaît comme un protocole valide et rapide pour identifier les éléments clef (faciès, fractures et stylolites) qui jouent un rôle dans la distribution des hétérogénéités pétrophysiques des réservoirs non-conventionnels. Cette méthode permet aussi de générer des modèles équiprobable de corps géologiques fracturés et perméables permettant de possible investigations sur la distribution des zones d’écoulement préférentielsHemipelagic limestones from the South-East of France are characterized by low values of porosity and permeability that allow considering these rocks as potential analogs to unconventional oil and gas reservoirs or fissured aquifers. These reservoirs are of primary importance in today’s economical context where the energy and the water’s demands grow with the increase in the world population. Nevertheless, the industrial exploitation of such reservoirs faces series of environmental risks and technical challenges that require to be managed in order to reduce their footprint on the environment.This work brought a significant amount of new data on unconventional carbonate reservoirs. It highlights how important compaction features (stylolites, microstylolites, solution seams) may be to fluids storage in such reservoirs. It shows that the diagenetic evolution of hemipelagic carbonate sediments depends on both early processes (sorting, early cementation, differential compaction) and eventual late reactivations (under tectonic stress inversion for example). Coupling three-dimensional modeling with geostatistics appear as an accurate and fast protocol to identify key elements (facies, fractures and stylolite) that play a role in the petrophysical heterogeneity of such unconventional reservoirs. This method also allows identifying equiprobable models of fractures geobodies and investigating the distribution of flow preferential pathways
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El, Mansour Nadia. "Caractérisation physico-chimique de la carbonatation minérale des résidus miniers ultramafiques de la région de Thetford Mines, Québec". Master's thesis, Université Laval, 2019. http://hdl.handle.net/20.500.11794/33851.
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L’origine de la croissance très rapide des émissions des gaz à effet de serre est attribuée, pour plus des ¾, au seul dioxyde de carbone (CO₂). Ce dernier engendre d’importants impacts sur l’équilibre thermique de la Terre, sur l’environnement et sur la biodiversité. Il est donc nécessaire de mettre en oeuvre des actions d’envergure pour réduire ces émissions. La carbonatation minérale est l’une des méthodes de la séquestration du CO₂, qui participe significativement à l’effort global de réduction des émissions d’origine anthropique dans l’atmosphère. Plusieurs auteurs ont montré que le processus de carbonatation minérale se produit naturellement en surface de la halde à résidus miniers de la mine LAB Chrysotile à Thetford Mines, Québec (Canada). L’objectif de ce projet est de trouver les évidences de la carbonatation minérale en soussurface de la halde à résidus miniers en caractérisant les phases minérales carbonatées des échantillons d’un forage de 90 m de profondeur et en identifiant les horizons présentant un fort potentiel de carbonatation minérale. Un total de 42 échantillons de forage a été prélevé à différentes profondeurs puis tamisés, broyés et analysés par les méthodes suivantes : analyseur élémentaire carbone-soufre, appareil infrarouge à transformée de Fourier-ATR, microfluorescence des rayons X et le microscope électronique à balayage. Les résultats ont montré la présence de l’artinite, la nésquehonite, la dypingite et l’hydromagnésite dans tous les échantillons analysés cela prouve que les minéraux carbonatés sont stable à l’intérieure de la pile de résidu. Cependant les minéraux ont peutêtre précipité à la surface puis avoir été subséquemment enfouis par d’autres résidus. La corrélation entre les absorbances, la teneur en carbone, les mesures de la résistivité et de la susceptibilité magnétique montre que la carbonatation minérale s'est produite d’une manière très hétérogène tout au long du forage, mais que les horizons aux profondeurs entre 15-20 m, 24-29 m, 37-42 m, 57 m, 65-69 m, 80-84 m et à 89 m ont une concentration significative en carbonates de magnésium hydratés.
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Nourtier-Mazauric, Elise. "Modélisation géochimique et numérique des interactions entre des solutions solides et une solution aqueuse. Extension du logiciel de réaction-transport Archimède et application à la diagénèse minérale des réservoirs". Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2003. http://tel.archives-ouvertes.fr/tel-00088991.
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Cette thèse présente un modèle thermodynamique et cinétique des interactions entre un fluide et des solutions solides idéales à plusieurs pôles. La réaction entre une solution solide et la solution aqueuse résulte de la compétition entre la dissolution stoechiométrique de la solution solide initiale et la coprécipitation de la solution solide la moins soluble dans le fluide à l'instant considéré.Ce modèle a été intégré au logiciel de transport réactif en milieu poreux ARCHIMEDE, puis appliqué à divers exemples. Dans le cas de solutions solides binaires, une méthode graphique a permis de déterminer les compositions des solutions solides qui précipitent, à l'aide des potentiels chimiques des pôles.
Le logiciel ainsi obtenu pourrait être utilisé pour modéliser notamment la diagenèse des réservoirs pétroliers argileux ou carbonatés, ou la dispersion de polluants dans le sol.
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Junior, Jairo Calderari de Oliveira. "Processos pedogenéticos atuais e pretéritos em solos alcalino-sódicos do Pantanal Norte". Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-15042015-153823/.
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A ocorrência de solos sódicos é comumente relacionada a regiões de clima semiárido ou condições de drenagem fechada (endorreica), e ambientes evaporativos. No Pantanal brasileiro, conhecido como a maior área inundável continental do mundo, os solos sódicos possuem significativa expressão em termos de área e funcionalidade ambiental, pela especificidade no desenvolvimento de plantas e no consumo intencional do solo por diversos animais e servindo como refúgio durante a cheia. Estes solos estão localizados nas partes mais elevadas da paisagem (paleodiques), situação diversa da maioria dos casos. Os processos pedogenéticos em solos sódicos do Pantanal Norte foram estudados na Reserva Particular do Patrimônio Natural (RPPN) SESC-Pantanal, no município de Barão de Melgaço-MT, em paleodiques de cinco setores em diferentes estádios de dissecação. Para tanto foram utilizadas descrições morfológicas em diversas escalas, datações de 14C em precipitados de carbonato e por luminescência opticamente estimulada (LOE) em sedimentos, modelagens geoquímicas e mineralógicas, análises espaciais de atributos químicos e físicos do solo, levantamento da condutividade elétrica aparente com sensor eletromagnético (EM-38) e estatísticas multivariadas. Nos solos dos setores mais conservados, foram observadas feições típicas de ambiente sedimentar lêntico, lâminas de carbonato de cálcio e ocorrência de diatomáceas, sugerindo que a formação das feições ocorreu pela concentração de águas. Esses ambientes ocorreram em condições de drenagem distintas das atuais, em que as planícies de inundação permaneciam isoladas, com limitações de drenagem lateral e vertical, promovendo a perda d\'água por evapotranspiração e consequentemente concentrando os íons em solução. A simulação da evaporação das águas dos rios São Lourenço e Cuiabá apresentaram resultados similares, indicando que ambos poderiam resultar na precipitação de calcita e saturação do Na+ no complexo de troca. Entretanto as feições observadas na morfologia do perfil como nas lâminas delgadas sugerem que os solos sódicos atualmente estão em degradação. A argiluviação é muito intensa e se destaca como principal processo de transformação desses solos, ocorrendo desde os mais conservados até em estádio mais avançado de dissecação. A ferrólise é evidente no estádio mais avançado de transformação dos solos, na transição entre E e Bt onde se estabelece uma porosidade cavitária por depleção tanto mecânica como química. Os carbonatos associados a canais, antigos poros e sem córtex definido, sugerem que as condições atuais não favorecem a sua formação. As análises mineralógicas indicam a presença de esmectita na parte mais preservada do paleodique, que nas condições atuais sofre interestratificação esmectita-caulinita. A hidrologia atual promove a erosão gradativa dos paleodiques que, anteriormente isolavam as lagoas, passando a uma drenagem mais aberta. A análise de componentes principais (ACP) identificou o processo redox como predominante na área de estudo e, em conjunto com os eventos de inundação, são os principais responsáveis pelas transformações dos solos. A via de transformação de solos nos paleodiques da RPPN SESC Pantanal foi LUVISSOLO-PLANOSSOLO. Estes últimos são muito susceptíveis ao processo de erosão promovido pela inundação e tendem a desaparecer, estreitamento a cordilheira progressivamente. A erosão acaba deixando pequenas elevações circulares denominadas de murundus, com elevados teores de Na+.Sodic soils are commonly associated to semi-arid climates, closed drainage systems (endorheic) and evaporative environments. In Brazilian Pantanal, knowns as the largest continental flooded area in the earth, sodic soils have significant expression in terms of area and environmental functionality, the specificity on plants development and soil intentional consumption (geophagy) by several animals, also playing as a refuge along the flooding events. These soils are located in the higher ground of the landscape (paleodiques), different from common situation. Pedogenic processes on north Pantanal sodic soils were studied in the Private Natural Heritage Reserve (PRNP) SESC Pantanal, in Barão do Melgaço-MT, performed on \"paleodiques\" from five sectors at different dissection stages. Pedogenic process was studied by means of morphologic descriptions was done in various scales, 14C dating on carbonate precipitates and optically stimulated luminescence (OSL) in sediments, geochemical and mineralogical modeling, spatial analysis of chemical and physical properties of the soil, apparent soil electrical conductivity performed by sensor electromagnetic (EM-38) and multivariate statistics. Soil profile from more conserved sectors shows typical features of lentic sedimentation environment, calcium carbonate layer and diatoms occurrence, suggesting that the formation of these features occurred by water concentration. Current condition is the opposite from earlier, wherein the flood plains remained isolated, with limited lateral and vertical drainage promoting water loss by evaporation and therefore concentrating the ions in solution. Simulation of the evaporation of water from São Lourenço and Cuiabá rivers points out similar results, suggesting that water evaporation from both could result in calcite precipitation and Na+ saturation in exchange complex. However, the features observed in both, field morphology and thin sections suggested that sodic soils are currently in degradation. The argilluviation is very intense and stands out as the main transformation process of these soils, occurring from the most preserved even in the most advanced dissection stage of. The ferrolysis is evident in the most advanced stage processing at E and Bt transition, where it establishes a cavity porosity depletion by both mechanical and chemical. Carbonates associated with channels, old pores and channels, without a cortex, suggests the current conditions do not favor sodic soil formation. Mineralogical analyzes indicates smectite presence in the paleodique of the most preserved sector, while present conditions promotes a smectite-kaolinite interestratification. Current hydrology promotes the gradual erosion of paleodiques that previously isolated the lakes from each other, becoming a slight open drainage system. The principal component analysis (PCA) identified the redox process as major process in the study area and, along the flood events, are primarily responsible for soil transformations. Pathway of sodic soil transformation in the RPPN SESC Pantanal paleodiques was Typic Natrudalf-Glossic Natraqualf. The latter are very susceptible to erosion process, promoted by flooding and tend to disappear, narrowing the paleodique progressively. Erosion process results in smalls and circulars elevations, named mounds, with high levels of Na+.
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Al, Qabany Ahmed Abdul Aziz. "Microbial carbonate precipitation in soils". Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609845.
Texto completoLibros sobre el tema "Sols carbonatés"
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P, Le Tirant y Nauroy Jean-François, eds. Foundations in carbonate soils. Paris: Editions Technip, 1994.
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R, Lal, ed. Global climate change and pedogenic carbonates. Boca Raton, Fla: Lewis, 2000.
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Geological Survey (U.S.), ed. The distribution of calcium carbonate in soils: A computer simulation using program CALSOIL. [Denver, Colo.]: U.S. Dept. of the Interior, Geological Survey, 1986.
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Geological Survey (U.S.), ed. The distribution of calcium carbonate in soils: A computer simulation using program CALSOIL. [Denver, Colo.]: U.S. Dept. of the Interior, Geological Survey, 1986.
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Kamilov, O. K. Genezis i svoĭstva okarbonachenno-zagipsovannykh pochv T͡S︡entralʹnoĭ Fergany. Tashkent: Izd-vo "Fan" Akademii nauk Respubliki Uzbekistan, 1992.
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Nettleton, W. D., ed. Occurrence, Characteristics, and Genesis of Carbonate, Gypsum, and Silica Accumulations in Soils. Madison, WI, USA: Soil Science Society of America, 1991. http://dx.doi.org/10.2136/sssaspecpub26.
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D, Nettleton W. y Soil Science Society of America. Division S-5., eds. Occurrence, characteristics, and genesis of carbonate, gypsum, and silica accumulations in soils. Madison, Wis., USA: Soil Science Society of America, 1991.
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G, Tindle A. y Webb P. C, eds. Geochemical reference material compositions: Rocks, minerals, sediments, soils, carbonates, refractories & ores used in research & industry. Latheronwheel, Caithness, U.K: Whittles Pub., 1992.
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El-Gobbi, Mahgub Omar. The effect of organic matter in corporation on the behaviour of calcareous growing media. Dublin: University College Dublin, 1997.
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Canada, Geological Association of, Canadian Geological Foundation, Devon Energy Corporation, University of Saskatchewan y Geological Association of Canada. Meeting, eds. Dynamics of epeiric seas. [St. John's, Nfld.]: Geological Association of Canada, 2008.
Buscar texto completoCapítulos de libros sobre el tema "Sols carbonatés"
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Lutenegger, Alan J. "Carbonate Content". En Laboratory Manual for Geotechnical Characterization of Fine-Grained Soils, 71–84. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9781003263289-7.
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Coop, M. R. y J. D. McAuley. "Shaft Friction of Piles in Carbonate Soils". En Advances in Underwater Technology, Ocean Science and Offshore Engineering, 645–59. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-017-2473-9_30.
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Hallmark, C. T. "Family Mineralogy of Soils with Free Carbonates and Gypsum". En SSSA Special Publications, 53–60. Madison, WI, USA: Soil Science Society of America and American Society of Agronomy, 2015. http://dx.doi.org/10.2136/sssaspecpub16.c4.
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Whittig, L. D. y P. Janitzky. "Mechanisms of Formation of Sodium Carbonate in Soils". En Selected Papers in Soil Formation and Classification, 367–78. Madison, Wisconsin, USA: Soil Science Society of America, Inc., 2015. http://dx.doi.org/10.2136/sssaspecpub1.c30.
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Virto, Iñigo, Isabel de Soto, Rodrigo Antón y Rosa M. Poch. "Management of carbonate-rich soils and trade-offs with soil inorganic carbon cycling". En Understanding and fostering soil carbon sequestration, 707–36. Burleigh Dodds Science Publishing, 2022. http://dx.doi.org/10.19103/as.2022.0106.22.
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Carbonate-rich soils are common in many arid and semiarid areas. Many of them are cultivated, and agriculture is expanding by the spreading of irrigation. Although the soil mineral fraction has been usually considered little or not affected by agricultural management in the short term, increasing evidence suggests that this is not the case for carbonates in the tilled layer. The consequences of management can be intense and depend on the modifications induced in inorganic carbon cycling, which can result in gains or losses of total inorganic soil C, and in changes in its type (pedogenic vs. lithogenic), size and distribution. Net soil CO2 emissions and interactions with organic C cycle can be affected by these changes, thereby altering soil organic matter dynamics. This chapter summarizes the major observed effects of agricultural practices potentially altering soil carbonates, includes a case study in a newly irrigated area, and identifies the most important knowledge gaps and research perspectives.
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Sposito, Garrison. "Soil Salinity". En The Chemistry of Soils. Oxford University Press, 2016. http://dx.doi.org/10.1093/oso/9780190630881.003.0016.
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A soil is salineif the electrical conductivity of its soil solution as obtained by extraction from a water-saturated soil paste (ECe) exceeds 4 dS m-1. (The measurement of electrical conductivity for a soil saturation extract is discussed in Methods of Soil Analysis,listed under For Further Reading at the end of this chapter.) According to this definition, about a quarter of the agricultural soils worldwide are saline, but values of ECe > 1 dS m-1 are encountered typically in arid-zone soils, which cover almost one-third of the global ice-free land area. Ions released into the soil solution by mineral weathering, or introduced there by the intrusion of saline surface water or groundwater, tend to accumulate in the secondary minerals formed as the soils dry. These secondary minerals typically include clay minerals (Section 2.3), carbonates and sulfates (Section 2.5), and chlorides. Because Na, K, Ca, and Mg are brought into the soil solution relatively easily—either as displaced exchangeable cations or as cations dissolved from carbonates, sulfates, and chlorides—it is this set of four metals that contributes most to soil salinity. The corresponding set of anions that contributes to salinity is CO3, SO4, and Cl. Thus, arid-zone soil solutions are essentially electrolyte solutions containing chloride, sulfate, and carbonate salts of four metal cations. According to Eq. 4.21, an electrical conductivity of 4 dS m-1 corresponds to an ionic strength of 58 mM (log I = -1.841 + 1.009 log4 = 0.0584). This level of salinity is less than 10% of that of seawater (EC = 46.21 dS m-1), but high enough that only crops that are relatively salt tolerant can withstand it. Moderately salt-sensitive crops are affected when the electrical conductivity of a soil saturation extract approaches 2 dS m-1, corresponding to an ionic strength of 29 mM, and salt-sensitive crops are affected at 1 dS m-1 (I = 14 mM). Thus, with respect to crop salinity tolerance, a soil can be judged saline at any saturation extract ionic strength greater than 15 mM if crops are stressed.
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Aitken, R. A. y K. M. Aitken. "With Carbonates". En Nitro, Nitroso, Azo, Azoxy, and Diazonium Compounds, Azides, Triazenes, and Tetrazenes, 1. Georg Thieme Verlag KG, 2010. http://dx.doi.org/10.1055/sos-sd-041-00233.
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Beignet, J. "Using Carbonates". En Three Carbon-Heteroatom Bonds: Acid Halides; Carboxylic Acids and Acid Salts, 1. Georg Thieme Verlag KG, 2007. http://dx.doi.org/10.1055/sos-sd-020-01269.
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Stien, D. "From Carbonates". En Three Carbon-Heteroatom Bonds: Esters and Lactones; Peroxy Acids and R(CO)OX Compounds; R(CO)X, X=S, Se, Te, 1. Georg Thieme Verlag KG, 2005. http://dx.doi.org/10.1055/sos-sd-021-00008.
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Maltman, Alex. "How Minerals Work". En Vineyards, Rocks, and Soils. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780190863289.003.0007.
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We might expect the ground of vineyards to consist of bewildering permutations of elements, but because its composition is dominated by just eight of them and there are chemical restrictions on how they can combine, the number of common minerals is not huge. Even so, their names are not particularly well known, even those of the very minerals that make the ground we live on and the soils that vines grow in. Mineral names that might spring to mind are more likely to be those used in jewelry or that are commercially mined. Such gemstones and ore minerals are not widespread, but geological processes have concentrated them in certain parts of the Earth, and if we can locate these accumulations, it may be worthwhile to extract them for profit. The rocks and soils that mainly concern us here are composed of silicate minerals, and Chapter 3 is devoted to these workhorses. They are sometimes called the “rock-forming minerals,” though there is an outstanding exception to this term: calcium carbonate, which makes the calcareous rocks. So in this chapter’s survey of the kinds of nonsilicate minerals we may come across in vineyards, we will pay particular attention to the carbonates. But first, let’s examine some fundamental concepts concerning the nature of minerals. As we saw in Chapter 1, minerals are made of ions bonded together through giving or sharing electrons. But to achieve this linkage, the ions cannot combine in some higgledy-piggledy fashion; rather, they have to organize themselves in a particular, symmetrical physical arrangement. It’s a bit like the sight of soldiers on formal parade. We call the three-dimensional framework of ions a lattice, and it’s this regular pattern that makes the material crystalline; it is a crystal. In other words, the pieces of mineral in a vineyard are crystalline. We may think of crystals as having the attractive, light- catching facets seen in gem shops and museums. Although this is a manifestation of the crystalline structure of the constituent ions, it is not what defines them as crystals. Consequently, minerals lying in a vineyard may be dull, shapeless chunks, but they are still crystals.
Actas de conferencias sobre el tema "Sols carbonatés"
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Skripnikov, P. y A. Nalivaichenko. "ACCUMULATION OF ORGANIC CARBON UNDER WOODY PLANT COMMUNITIES IN URBAN FORESTS OF ROSTOV-ON-DON". En Reproduction, monitoring and protection of natural, natural-anthropogenic and anthropogenic landscapes. FSBE Institution of Higher Education Voronezh State University of Forestry and Technologies named after G.F. Morozov, 2022. http://dx.doi.org/10.34220/rmpnnaal2021_97-102.
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The paper provides an analysis of the vegetation state and soil cover of the "Temernitskaya Roscha" and the "Schepkinsky Les" artificial recreational forests which located in the Rostov-on-Don city. Geobotanical descriptions were carried out according to the standard method to species diversity assessing. The “Temernitskaya Roscha" recreational forests has been affected by anthropogenic pressure, but its grass cover was more diverse than in the "Schepkinsky Les" recreational forests where tree plant species was dominated. The study of the soil cover revealed a statistically significant increase of the organic matter content in the AUrz surface horizon. This increase was noted in soils under woody vegetation, in comparison with steppe zones which are typical for our region. In the underlying AU horizons, the accumulation and distribution of Corg, in turn, has a similar character for all studied soils. There are no significant differences between the chernozems of the forest park zone and fallow territories in the accumulation and distribution of Corg. The calcium carbonates profile distribution under woody vegetation is characterized by a decrease in the carbonated depth, visual blurriness of the presence of carbonates and the presence of rarely encountered lime nodules in the lower part of the profile.
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Thi, Bang Le, Hoang Quoc Khai, Bui Duc Long y S. Ramesh. "Fabrication of nanoparticle carbonated hydroxyapatite by phase transformation of calcium carbonate prepared by sol-gel hydrothermal method". En 8TH BRUNEI INTERNATIONAL CONFERENCE ON ENGINEERING AND TECHNOLOGY 2021. AIP Publishing, 2023. http://dx.doi.org/10.1063/5.0113867.
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Yadla, Nanda Kishore, Rama Mohan Gajulapalli, Kandasamy K. K y Faris Kamal. "Optimization of Jacket Structure in Carbonate Soils". En The 7th World Congress on Civil, Structural, and Environmental Engineering. Avestia Publishing, 2022. http://dx.doi.org/10.11159/icgre22.210.
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Avakyan, A. A. "ABOUT THE CRYSTALLIZATION OF STIBNITE FROM THE AQUEOUS SOLUTIONS OF HYDROGEN SULPHIDE AND ABOUT THE COMPOSITION OF THESE SOLUTIONS". En Проблемы минералогии, петрографии и металлогении. Научные чтения памяти П. Н. Чирвинского. ПЕРМСКИЙ ГОСУДАРСТВЕННЫЙ НАЦИОНАЛЬНЫЙ ИССЛЕДОВАТЕЛЬСКИЙ УНИВЕРСИТЕТ, 2022. http://dx.doi.org/10.17072/chirvinsky.2022.3.
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The aqueous solutions of the amorphous Sb2S3 is not the hydrophobic sols. The amorphous Sb2S3 reacts with H2O and/or H2S (in aqueous solutions); result: – hy-drophilic thioacids, same as the As2O3 reacts with H2O (As2O3 + 3H2O ⇄ 2H3AsO3); this is a reversible reaction. The arsenous acid decomposes to give crystals of the As2O3 (this is a recrystallization process). The solution of the amorphous Sb2S3 in the H2O with H2S give the crystals of the stibnite, and this process can proceed at room conditions. H2CO3 does not decompose this solutions. H2CO3 + insoluble carbonates – this is a buffering system, which stabilizes the solutions of antimonous thioacids and, consequently, stabilizes the process of crystallization of stibnite. Therefore, the insoluble carbonates — this is a common associates of stibnite
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Brandes, Horst G. "Permeability of Marine Sediments and Tropical Volcanic Soils". En ASME 2012 31st International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/omae2012-83543.
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Permeability values for a range of fine-grained deep-sea sediments are presented and evaluated in terms of index properties such as plasticity, grain size and carbonate content. It is found that whereas clay-rich sediments have similar permeabilities to those of equivalent land-based fine-grained soils, the presence of volcanic, carbonate and other non-clay fractions tends to increase permeability somewhat. Volcanic silty-clayey soils from Hawaii have comparable permeability values, although they can be slightly more permeable.
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Beavers, J. A. y R. G. Worthingham. "The Influence of Soil Chemistry on SCC of Underground Pipelines". En 2002 4th International Pipeline Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/ipc2002-27146.
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High-pH stress corrosion cracking (SCC) failures of underground pipelines have occurred in a wide variety of soils, covering a range in color, texture, and pH. No single characteristic has been found to be common to all of the soil samples. Similarly, the compositions of the water extracts from the soils have not shown any more consistency than the physical descriptions of the soils. On several occasions, small quantities of electrolytes have been obtained from beneath disbonded coatings near locations where high-pH stress corrosion cracks were detected. The principle components of the electrolytes were carbonate and bicarbonate ions and it is now recognized that a concentrated carbonate-bicarbonate environment is responsible for this form of cracking. Much of this early research focused on the anions present in the soils and electrolytes. This paper summarizes the results of analyses of soil and electrolyte data in which the relationship between the cations and the occurrence of high-pH and near-neutral pH SCC were evaluated.
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Stupar, Vladanka, Markola Saulić, Milica Blažić, Zlata Živković, Darko Stojićević, Marko Stokić y Bojan Stević. "STATE OF SOIL FERTILITY IN THE AREA OF THE POŽAREVAC CITY". En 1st International Symposium on Biotechnology. University of Kragujevac, Faculty of Agronomy, 2023. http://dx.doi.org/10.46793/sbt28.289s.
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Soil analysis provides information about the quality of the soil and the input of nutrients that are needed to make the soil better and obtain a high crop yield. The research in this paper included the analysis of fertility parametars of soil in wider territory of the Požarevac city during 2017 and 2022 year. Soil analysis shows that average soil acidity, i.e. its pH value of the aqueous soil solution (pH – H2O), in 2022 was reduced by 0.28 compared to 2017. On other hand, the substitution acidity (pH – KCl) was reduced by 0.49 after 5 years. The results for CaCO3 show that the soils are generally carbonate-free or weakly carbonated , well supplied with humus and the percentage of contetnt of N decreased by 21.91% in the five-year period. Low content of easily accessible phosphorus was identified in both year in over 50 percentage of the soil samples while mostly soil samples are well supplied with easily accessible potassium.
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Cao, Jianchun, Zhibin Zhong y Ashish Budhiraja. "Numerical Investigation on Suction Pile’s Holding Capacity Installed in Carbonate-Type Soils". En ASME 2020 39th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/omae2020-18107.
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Abstract Suction piles have not been widely used in carbonate-type soils (i.e., muds/silts) because the pile skin frictions in this type of soils are only about 5% of that in normal clayey soils. The holding capacity of a suction pile installed in these types of soils may be affected by its lower friction. Moreover, pile designers have concerns not only on the development of the Reverse End Bearing (REB) but also on how long the REB can sustain. This paper presents the development of a three-Dimensional Finite Element Analysis (3D FEA) model and the analysis results to investigate the behavior of suction pile for different levels of skin frictions. Firstly, the FEA model is used to investigate the development of the Reverse End Bearing (REB) of a suction pile by assigning two different levels of pile external skin frictions, i.e., 5% and 100% (full skin friction). A vertical load is applied at the center of the pile top. Secondly, the FEA model is used to investigate the behavior of a suction pile for a very low level of pile skin friction (i.e., 5% skin friction). An inclined load with various load angles from horizontal is applied at the padeye (i.e., 16m below seabed). Thirdly, the load carrying (failure) mechanism has been checked by examining the total displacement vectors of soil masses around the pile. Fourthly, a sensitivity study is carried out to investigate the capacity of a suction pile for different usage factors of REB. Finally, suction pile design requirements for carbonate-type soils (i.e., low level of pile skin frictions) are recommended.
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Brunning, Paul y Baidrul Ishak. "Improved Pile Driving Predictions in Carbonate Soils and Rock". En Offshore Technology Conference. Offshore Technology Conference, 2012. http://dx.doi.org/10.4043/23232-ms.
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Lehane, Barry M., J. Antonio H. Carraro, Nathalie Boukpeti y Sarah Elkhatib. "Mechanical Response of Two Carbonate Sediments From Australia’s North West Shelf". En ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/omae2014-23340.
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The carbonate sediments found offshore on the North West Shelf of Australia can generally be described as silts with varying proportions of clay-sized and sand-sized carbonate particles. This paper investigates the undrained shearing response (as measured under simple shear and triaxial conditions) of two sediments with different grading curves. The importance of the fines content in controlling the density and hence dilatancy and undrained strength of the materials is demonstrated. The paper discusses the importance of fabric to the behavior of these soils and provides guidance on how undrained strengths of soils of this nature may be assessed with a knowledge of a material’s in-situ water content (or void ratio) and composition.
Informes sobre el tema "Sols carbonatés"
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Francis, C. W., S. Y. Lee, J. H. Wilson, M. E. Timpson y M. P. Elless. The use of carbonate lixiviants to remove uranium from uranium-contaminated soils. Office of Scientific and Technical Information (OSTI), agosto de 1997. http://dx.doi.org/10.2172/510339.
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Reeder, Richard J. Spectroscopic and Microscopic Characterization of Contaminant Uptake and Retention by Carbonates in Soils and Vadose Zone Sediments. Office of Scientific and Technical Information (OSTI), junio de 2001. http://dx.doi.org/10.2172/833624.
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Wilson, J. H., R. Chernikoff y W. D. DeMarco. Carbonate and citric acid leaching of uranium from uranium-contaminated soils: Pilot-scale studies (Phase II). Office of Scientific and Technical Information (OSTI), octubre de 1995. http://dx.doi.org/10.2172/130633.
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Hunter, C. R. y A. J. Busacca. A feasibility study of modeling pedogenic carbonates in soils and sediments at the US Department of Energy's Hanford Site. Office of Scientific and Technical Information (OSTI), septiembre de 1990. http://dx.doi.org/10.2172/6553280.
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Russo, David y William A. Jury. Characterization of Preferential Flow in Spatially Variable Unsaturated Field Soils. United States Department of Agriculture, octubre de 2001. http://dx.doi.org/10.32747/2001.7580681.bard.
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Preferential flow appears to be the rule rather than the exception in field soils and should be considered in the quantitative description of solute transport in the unsaturated zone of heterogeneous formations on the field scale. This study focused on both experimental monitoring and computer simulations to identify important features of preferential flow in the natural environment. The specific objectives of this research were: (1) To conduct dye tracing and multiple tracer experiments on undisturbed field plots to reveal information about the flow velocity, spatial prevalence, and time evolution of a preferential flow event; (2) To conduct numerical experiments to determine (i) whether preferential flow observations are consistent with the Richards flow equation; and (ii) whether volume averaging over a domain experiencing preferential flow is possible; (3) To develop a stochastic or a transfer function model that incorporates preferential flow. Regarding our field work, we succeeded to develop a new method for detecting flow patterns faithfully representing the movement of water flow paths in structured and non-structured soils. The method which is based on application of ammonium carbonate was tested in a laboratory study. Its use to detect preferential flow was also illustrated in a field experiment. It was shown that ammonium carbonate is a more conservative tracer of the water front than the popular Brilliant Blue. In our detailed field experiments we also succeeded to document the occurrence of preferential flow during soil water redistribution following the cessation of precipitation in several structureless field soils. Symptoms of the unstable flow observed included vertical fingers 20 - 60 cm wide, isolated patches, and highly concentrated areas of the tracers in the transmission zone. Soil moisture and tracer measurements revealed that the redistribution flow became fingered following a reversal of matric potential gradient within the wetted area. Regarding our simulation work, we succeeded to develop, implement and test a finite- difference, numerical scheme for solving the equations governing flow and transport in three-dimensional, heterogeneous, bimodal, flow domains with highly contrasting soil materials. Results of our simulations demonstrated that under steady-state flow conditions, the embedded clay lenses (with very low conductivity) in bimodal formations may induce preferential flow, and, consequently, may enhance considerably both the solute spreading and the skewing of the solute breakthrough curves. On the other hand, under transient flow conditions associated with substantial redistribution periods with diminishing water saturation, the effect of the embedded clay lenses on the flow and the transport might diminish substantially. Regarding our stochastic modeling effort, we succeeded to develop a theoretical framework for flow and transport in bimodal, heterogeneous, unsaturated formations, based on a stochastic continuum presentation of the flow and a general Lagrangian description of the transport. Results of our analysis show that, generally, a bimodal distribution of the formation properties, characterized by a relatively complex spatial correlation structure, contributes to the variability in water velocity and, consequently, may considerably enhance solute spreading. This applies especially in formations in which: (i) the correlation length scales and the variances of the soil properties associated with the embedded soil are much larger than those of the background soil; (ii) the contrast between mean properties of the two subdomains is large; (iii) mean water saturation is relatively small; and (iv) the volume fraction of the flow domain occupied by the embedded soil is relatively large.
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Hydrologic characteristics of soils in the High Plains, northern Great Plains, and Central Texas Carbonates Regional Aquifer Systems. US Geological Survey, 1990. http://dx.doi.org/10.3133/ha714.
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