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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.
141

Clay mineralogy and other petrologic aspects of the Grenola limestone formation in the Manhattan, Kansas, area

Hargadine, Gerald D. January 1959 (has links)
Call number: LD2668 .T4 1959 H37
142

Petrology and stratigraphy of the Colina limestone (Permian) in Cochise County, Arizona

Wilt, Jan Carol January 1969 (has links)
No description available.
143

Nitrat i grundvattnet : Modellanalys av vattenflöde till Hörviks vattentäkt / Nitrate in the groundwater : Model analysis of water flow to Hörvik’s water supply

Petersson, Terje January 2004 (has links)
<p>A well, situated on Listerlandet in the western part of Blekinge in Sweden, has a very high content of nitrate. Water with a too high content of nitrate is hazardous to human health, in particular to small children. The area surrounding the well is mostly drained agricultural land with some larger farms for chicken and mink. The well takes its water from the bedrock and is deeper than most other wells affected by nitrate. The bedrock in the area is dominated by limestone with a relatively high flow of water.</p><p>This thesis was performed in order to find the source of the nitrate. A groundwater model, simulating the water flow, was created. The model was used to trace the particles flowing to the well in order to find the most likely source. GMS Modflow and Modpath were used to create the model.</p><p>The validation of the model shows that the model is good enough to be used for further investigation of the groundwater in the area.</p><p>The model result indicates that the original source for most of the nitrate is some large mink farms situated on the slope of a hill south of the well. Calculation shows that it takes the water 25 years to flow from the farms to the well. There is also a probable contribution of nitrate from the agriculture in the vicinity of the well. But an extensive drainage system brings most of the water from the cultivated area into the Baltic Sea.</p><p>Conclusions are that a large amount of mink farms placed in a small area contributes to the high content of nitrate in the well. Further examinations are needed to show which measures should be taken in order to diminish the content of nitrate in the well.</p> / <p>En brunn som förser Hörvik med dricksvatten har en hög halt av nitrat. Hörvik ligger på Listerlandet i västra Blekinge. Vatten med för hög nitrathalt är hälsovådligt för människor i allmänhet och spädbarn i synnerhet.</p><p>Området som omger brunnen består till största delen av dränerad jordbruksmark med några större djurgårdar för broiler och mink. Brunnen är bergborrad och går djupare än de flesta andra nitratpåverkade brunnar i Sverige. Berggrunden i området domineras av kalkberg med ett relativt högt vattenflöde.</p><p>Ett projektarbete utfördes för att ta reda på ursprungskällan till nitratet. I arbetet skapades en grundvattenmodell som skulle simulera vattenflödena i området och sedan spåra en partikels väg till brunnen för att ta reda på den mest troliga källan. GMS Modflow och Modpath är de dataverktyg som användes.</p><p>Valideringen av modellen visar att den fungerar tillfredsställande och kan användas för fortsatta undersökningar av grundvattenförhållanden i området.</p><p>Modellresultat tyder på att ursprungskällan för den största delen av nitratet är några stora minkfarmar som ligger på en sluttning upp mot Listers huvud söder om brunnen; dock har det tagit ca 25 år för vattnet att ta sig från ursprungskällan till brunnen. Jordbruket i närheten av brunnen bidrar sannolikt med en del nitrat, men en omfattande dränering leder den större delen av vattnet från jordbruksområdet ut i Östersjön.</p><p>Slutsatsen är att ett stort antal minkfarmar i ett begränsat område är en bidragande orsak till brunnens höga nitrathalt. Vidare undersökningar bör visa vilka åtgärder som behövs för att minska nitrathalten i brunnen.</p>
144

The classification and management of limestone pavements : an endangered habitat

Willis, Susan Denise Margaret January 2011 (has links)
This thesis describes an in-depth study of limestone pavements across North West England and North Wales. The aim was to combine elements of geodiversity and biodiversity in order to create a holistic limestone pavement classification to inform future management. A field-based research protocol was used to assess a stratified random sample (46 pavements), accounting for approximately 10% of the limestone pavements in the geographical area. Detailed analyses of key elements are presented, along with important issues that continue to pose threats to this Annex One Priority Habitat. This research resulted in a comprehensive classification, using TWINSPAN analysis and Nonmetric Multidimensional Scaling, identifying six distinct holistic functional groups. The prime factors driving limestone pavement morphology, and hence the classification, were established to be lithology, proximity to structural fault, altitude and human intervention, particularly in terms of grazing intensity. Three upland, open limestone pavement classes were formed. Of these, the richest in terms of geodiversity and biodiversity was the group with the thickest bedding planes and hence the deepest grikes, typically greater than 1m. The class that was most species-poor was "at the highest altitude (above 450m), formed on the thin limestones of the Yoredales. These were characterised by shallow, wide grikes. The third upland limestone pavement group had mid-range grikes, generally 0.5-1m in depth, and small clints. Two wooded classes were identified. One was a lowland 'classic' wooded limestone pavement group with deep, narrow grikes and shallow soils. Indicator species included Juniperus communis and Taxus baccata. The second wooded group was situated proximal to a major structural fault. In this group the pavement dip ranged between 10°-40° with well-runnelled clints that were heavily moss-covered. The sixth group was low altitude, proximal to the coast, characterised by low moss growth, un-vegetated clints and the presence of Ulex europaeus. Conservation management was identified as key to the quality of the limestone pavement habitat and this thesis identifies best management practises and links these to the holistic limestone pavement classification. Finally, as a sample case study, this thesis presents mollusc species and diversity from eleven of the Yorkshire limestone pavements. Analysis establishes significant links between geodiversity and mollusc populations, with key drivers for mollusc communities echoing those of plant species on limestone pavement.
145

Basin Analysis of the Porter Group, Castle Hill Basin, Canterbury: Implications for Oligocene Tectonics in New Zealand.

Congdon, Linda Marie January 2003 (has links)
A basin analysis of the Oligocene Porter Group rocks in Castle Hill Basin, Canterbury, was completed. The Porter Group contains the Coleridge Formation which comprises a lower sandstone unit and an upper micritic limestone unit, and the Thomas Formation which consists of biosparite limestone and interbedded tuffs. Basin analysis provided evidence that the Coleridge Formation lower sandstone unit was deposited in an inner shelf setting based upon its moderate sorting, large grain size range, laterally continuous geometry and lack of bedforms due to intense bioturbation. The upper micritic limestone is a mid shelf deposit composed of micrite and minor clastic grains. Provenance analysis has classified the lower sandstone unit as a quartz arenite. Both metamorphic and plutonic source areas are likely for the sandstone, along with reworked grains from underlying Formations based on QFL, SEM-CL, heavy mineral and glauconite analysis. The Thomas Formation limestone is a typical New Zealand cool water biosparite deposited on the inner shelf as a result of storms and debris flows, with the upper cross-bedded limestone lithofacies being reworked by currents in shallow water. Petrographic data showing multiple stages of diagenesis at the upper contact of the Thomas Formation provides evidence for a major tectonic event. The interbedded tuffs are a result of basaltic marine volcanism on the inner to mid shelf. The tuffs are reworked and deposited by turbidity current, debris flow and storms. Analysis of a dike within the Thomas Formation volcanics showed a weakly alkaline geochemical signature that is indicative of volcanism related to extension. A regional synthesis compared the Porter Group rocks in Castle Hill Basin with Oligocene rocks in North Canterbury, West Coast and North Otago. Oligocene quartz-rich sandstones are found in Castle Hill Basin, Harper Valley, Avoca and Culverden while micritic limestone is found on the East Coast from Marlborough to Otago. Oligocene basaltic volcanics interbedded with limestone and karst unconformities are found in Castle Hill Basin, Culverden and Otago. Normal faulting may be responsible for thickness variations and several regional karst unconformities in the eastern South Island. Plate reconstructions based on sea floor magnetic anomalies also suggests the New Zealand region was tectonically active during the Oligocene. Mounting evidence, including Eocene-Oligocene faulting and volcanism in the South Island, suggests that New Zealand may not be best described as a passive margin during the Early-Mid Tertiary.
146

紀伊半島中央部洞川地域の鍾乳洞産哺乳類化石の炭素14年代(予察)

Tanaka, Daisuke, Abe, Yuji, Kashiwagi, Kenji, 田中, 大祐, 阿部, 勇治, 柏木, 健司 03 1900 (has links)
タンデトロン加速器質量分析計業績報告
147

Consolidant particle transport in limestone, concrete and bone

Campbell, Alanna Stacey January 2013 (has links)
The use of chemically compatible nano and fine particle colloidal consolidants is a new development within the field of cultural heritage conservation and applied most widely so far to the historic built environment. The ability to introduce a significantly higher quantity of chemically compatible consolidant to a substrate in fewer treatments with the possibility for greater penetration and fewer possible side-effects compared to more established consolidants is a significant advantage. This fundamental scientific study examines the effects of a colloidal calcium hydroxide (nanolime) consolidant on medieval and quarried limestone and autoclaved aerated concrete and the efficacy of a colloidal hydroxyapatite treatment on archaeological human bone. Both calcium hydroxide and hydroxyapatite were synthesised. Characterisation of both compounds was performed by X-ray diffraction spectroscopy and particle morphology was confirmed by electron microscopy. Particle size was determined by laser diffraction and particle tracking analysis techniques, used together to study these particle systems for the first time, and electron microscopy. The location of particles within treated substrates was established by electron and optical microscopy whilst effects on water transport were determined by imbibition experiments and numerical modelling. For the first time a modified sharp front model was applied to [particle-material]-material composites to aid the understanding of water transport in such materials. Mechanical testing was used to identify differences in material strength depending on treatment layer thickness and mercury intrusion porosimetry suggested extent of pore blocking. It was found that non-classical effects occur in the calcium hydroxide system synthesised in this study and that particle stability can be influenced by reagent concentration. For the first time material sorptivity properties, modality and pore size distribution of Lincoln stone and archaeological bone are reported. The application of a nanolime consolidant to autoclaved aerated concrete allowed the nature of the particle transport through a highly complex material to be determined, showing that the particle concentration decreases with increasing penetration depth. Shallow nanolime particle penetration into limestone appeared ineffective on compressive strength. In a novel study the prospects of a hydroxyapatite consolidant treatment for bone were also evaluated, finding the results to be inconclusive in this small study. For all consolidants a small reduction in material water sorptivity after treatment demonstrated the permeable nature of the treatment layer and suggests the avoidance of damage mechanisms due to highly restricted water transport. Knowledge of the efficacy and location of treatment particles and their affect on water movement, particularly in weathered material, within limestones and archaeological bone is important and was determined for all materials used in this study. This work adds to the understanding of such treatments and their capabilities and the nature of the porous materials used herein.
148

Petrographic analysis and diagenetic history of the Viola limestone at Stephen’s Ranch, in the Morrison northeast field of Clark County, Kansas

Linares, Aria January 1900 (has links)
Master of Science / Department of Geology / Matthew Totten / The Viola Limestone is a prominent petroleum reservoir in the Mid-Continent Region, particularly in Oklahoma and Kansas. Coral Coast Petroleum established production from the Viola Ls. in 2011 in their Stephens Ranch lease in Clark County, south-central Kansas. Development of this lease has been hindered by the unpredictable production rates encountered in each of the subsequent eleven development wells. Infield drilling locations to date were chosen by favorable structural position as determined by 3D seismic. The best reservoir conditions, however, do not necessarily coincide with structural position. It was the purpose of this study to determine whether the ideal porosity and permeability are controlled by depositional environment, diagenetic alterations, or a combination of these factors. Several approaches to solve this question were implemented and utilized, including well log analysis, petrographic inspection of well cuttings and thin sections, and the application of the Scanning Electron Microscope (SEM). An exploration model of the Viola Ls. in this field was developed, where the Viola A and B zones were dolomitized during during marine transgressions by mixing of sea water with other Mg-rich fluids. Reservoir conditions are found where these facies were preserved as paleotopographic highs during a subsequent sea level low-stand. These preserved dolomitized facies correspond to the seismic facies identified by seismic attributes in a 3D seismic study by Vohs (2016).
149

Použití přenosného XRF spektrometru pro hodnocení kvality vápencové suroviny a odhad zásob na ložisku Mořina - východ (Velká Amerika) / Application of portable XRF spectrometer for evaluation of the quality of limestone ore and estimation of reserves at the Mořina - východ (Velká Amerika) deposit

Pechar, Tomáš January 2014 (has links)
The present thesis provides assessment potential of the Mořina - Východ deposit (Velká Amerika) as a raw material reserves for the Kozolupy - Čeřinka deposit. The reason for this work is limited lifetime of the Kozolupy - Čeřinka deposit (approx. 11-14 years) that does not allow fulfilling the requirement to ensure the production of limestone for flue gas desulphurization for ČEZ until 2035. Objective of this work is to summarize all the existing knowledge of the deposit and define the expected technological parameters of raw materials and consider the possibility of its use as a raw material for flue gas desulphurization. Special attention was paid to dolomitization of the limestone, namely to its extent and nature, because elevated Mg content lowers the quality of the limestone ore. Finally, ore reserve calculations and mining intentions are presented. On the basis of microscopic research two types of dolomite were distinguish: diagenetic and epigenetic. Diagenetic dolomite originated at shallow burial together with recrystallization of limestone slurry at temperatures up to 50 řC. Homogenization temperatures of primary fluid inclusions in epigenetic dolomite lay in the range 76-92 řC (sample A9) and 63-88 řC (sample A25).The trapping temperature of these inclusions was probably only slightly...
150

Efeito da distribuição granulométrica do calcário na absorção de SO2 em reator de leito fluidizado / not available

Fábio Ferreira da Silva 29 August 2003 (has links)
O principal objetivo deste trabalho foi obter parâmetros reativos para as reações de absorção de SO2 por calcários em leitos fluidizados e procurar correlacionar, através de dois modelos simples, os resultados obtidos para distribuições granulométricas amplas e estreitas. Foram estudadas cinco faixas estreitas, com diâmetros de 385, 460, 545, 650, 775 &#956m para dois tipos de calcários, um dolomítico (DP) e um calcítico (CI). A partir destas faixas estreitas foram compostas quatro misturas, com 498, 540, 543 e 617 &#956m. Um dos dois modelos foi usado para determinar a fração com que cada faixa estreita deveria estar presente na mistura. Uma das misturas, a Mistura 2 (540 &#956m), tinha distribuição de diâmetros aproximadamente normal e a outra, Mistura 3 (543 &#956m), distribuição plana. O leito, de 160 mm de diâmetro, foi fluidizado com ar à temperatura de 850ºC e utilizou areia como material particulado. O calcário foi introduzido em bateladas de 50 g em um leito de areia de mesmo diâmetro com cerca de 2,0 Kg de massa. Uma vazão de SO2 foi misturada ao ar antes que este entrasse no leito, de forma a resultar em uma concentração próxima à 1000 ppm na saída do reator. A concentração de saída foi monitorada e a sua queda, verificada após a introdução da batelada de calcário, foi utilizada em um modelo matemático para determinar os parâmetros reativos, entre eles a conversão, taxa de conversão e o coeficiente global de taxa de reação. Os modelos de distribuição granulométrica empregados produziram boa correlação entre as misturas e as faixas estreitas durante a sulfatação. Na calcinação, o processo mostrou-se mais lento para a distribuição ampla do calcário DP e não foi afetado para o CI. Em todos os casos estudados o diâmetro do calcário mostrou afetar significativamente e de forma inversa, a eficiência dos calcários na remoção do SO2. O calcário DP mostrou-se sempre mais eficiente do que o calcário CI. / The main objective of this work was to compare the reactivity of limestones with narrow and open particle size distribution in a bubling fluidized bed reactor and verify if the reactivity of the open sized mixtures could be predicted, using two simple models, from the known parameters of the narrow sized particles. Five narrow sizes were used, respectively 385, 460, 545, 650 and 775 &#956m for two different limestones, one calcitic (CI) and one Dolomitic (DP). Using this same material and one of the models, four mixtures were prepared with 498, 540, 543 and 617 &#956m of average diameter. The mixture of 540 &#956m had an aproximately normal distribution of sizes and the mixture of 543 &#956m a falt one. The bed, with 160 mm of diameter, was fluidized with air at a temperature of 850ºC, and 2 Kg of sand with the same size as the limestones, was used as the bed material. A flow of SO2 was mixed with the fluidization air prior to the gas distributor, producing a uniform concentration of about 1000 ppm at the reactor gas exaust. The limestone was then intoduced in a batch of 50 g and the SO2 concentration monitored. The change in the SO2 concentration after the limestone was intoduced in the reactor was used to derive the reactive parameters, namely the conversion, rate of conversion and global coefficient of reaction rate. The particle size distribution models produced a good correlation among the mixtures and the narrow sized particlesduring sulfatation. The calcination process was more slow for the open distribution of limestone DP but not affected for CI. In all cases there was a clear increase in the SO2 absorption as the particle size was reduced. Limestone DP was much more effective in the removal of SO2 than CI.

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