Dissertations / Theses: 'Geothermal areas'

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Savage, Shannon Lea. "Mapping changes in Yellowstone's geothermal areas." Thesis, Montana State University, 2009. http://etd.lib.montana.edu/etd/2009/savage/SavageS0809.pdf.

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Yellowstone National Park (YNP) contains the world's largest concentration of geothermal features, and is legally mandated to protect and monitor these natural features. Remote sensing is a component of the current geothermal monitoring plan. Landsat satellite data have a substantial historical archive and will be collected into the future, making it the only available thermal imagery for historical analysis and long-term monitoring of geothermal areas in the entirety of YNP. Landsat imagery from Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) sensors was explored as a tool for mapping geothermal heat flux and geothermally active areas within YNP and to develop a change analysis technique for scientists to utilize with additional Landsat data available from 1978 through the foreseeable future. Terrestrial emittance and estimates of geothermal heat flux were calculated for the entirety of YNP with two Landsat images from 2007 (TM) and 2002 (ETM+). Terrestrial emittance for fourteen summer dates from 1986 to 2007 was calculated for defined geothermal areas and utilized in a change analysis. Spatial and temporal change trajectories of terrestrial emittance were examined. Trajectories of locations with known change events were also examined. Relationships between the temporal clusters and spatial groupings and several change vectors (distance to geologic faults, distance to large water bodies, and distance to earthquake swarms) were explored. Finally, TM data from 2007 were used to classify geothermally active areas inside the defined geothermal areas as well as throughout YNP and a 30-km buffer around YNP. Estimations of geothermal heat flux were inaccurate due to inherent limitations of Landsat data combined with complexities arising from the effects of solar radiation and spatial and temporal variation of vegetation, microbes, steam outflows, and other features at each geothermal area. Terrestrial emittance, however, was estimated with acceptable results. The change analysis showed a relationship between absolute difference in terrestrial emittance and earthquake swarms, with 34% of the variation explained. Accuracies for the classifications of geothermally active areas were poor, but the method used for classification, random forest, could be a suitable method given higher resolution thermal imagery and better reference data.

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Murray, Ryan M. "The Search For Volatile Biogenic Emissions In Geothermal Areas." The University of Montana, 2007. http://etd.lib.umt.edu/theses/available/etd-12202006-152114/.

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A primary discipline of astrobiology is the search for life outside of the earths ecosystem. Detecting biosignatures in outer space is one way this search is conducted. To understand the biosignatures to look for and study in space, it is useful to gain a better understanding of life in diverse environments on earth. This research tested the hypothesis that chemicals characteristic of microbial life can be detected and quantified in air above hot springs with Fourier transform infrared spectroscopy (FTIR). The stated hypothesis was refuted, as no chemicals of uniquely biological origin were detected with FTIR. A discussion of why no uniquely biological chemicals were detected with FTIR is presented. An analysis of chemicals seen in the infrared spectra, such as CO2, is given in the context of their possible biological origin. The results of the CO2 analysis indicate that the naturally occurring biomats are more complex than laboratory cultures and that the observable results of the behaviors of the two groups cannot be directly related. Lastly, other data collected (water chemistry and weather data for the springs) and the results of water analysis (ion chromatography and total organic carbon) are summarized. Acetate, propionate, and formate were present in some springs at low levels, indicating chemically the presence of microbial activity.

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Galanopoulos, Dimitrios. "Magnetotelluric studies in geothermal areas of Greece and Kenya." Thesis, University of Edinburgh, 1989. http://hdl.handle.net/1842/10909.

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GAGLIANO, Antonina Lisa. "Gaseous emissions from geothermal and volcanic areas: focus on methane and methanotrophs." Doctoral thesis, Università degli Studi di Palermo, 2014. http://hdl.handle.net/10447/90855.

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Ogni anno, 22 Tg di CH4 vengono rilasciati in atmosfera da numerose sorgenti sia naturali che antropiche. Il metano riveste un ruolo molto importante nella chimica dell’atmosfera terrestre e nel bilancio dell’energia radiante assorbita, essendo il secondo gas serra più potente dopo la CO2. Le aree vulcaniche e geotermali contribuiscono al flusso di metano in atmosfera, essendo vaste aree di degassamento. Studi preliminari hanno stimato che le emissioni globali di metano dai sistemi geotermali e vulcanici europei sono nel range di 4-16 kt a-1. Questa stima è stata ottenuta indirettamente dai dati delle emissioni di CO2 o H2O e dal rapporto del flusso CO2/CH4 oppure H2O/CH4 misurati nelle principali fumarole. La stima del metano emesso globalmente dalle aree vulcaniche e geotermali non è ancora ben definita in quanto il bilancio tra le emissioni per degassamento dai suoli e il consumo di metano per ossidazione microbica è ancora poco noto. Inoltre, le misure di flusso di metano sono molto difficili da eseguire e si hanno a disposizioni pochi dati. Alcuni metodi, seppur accettabili al fine di ottenere stime sul flusso di metano, escludono completamente la possibilità che il metano venga rimosso per via microbica dai batteri metanotrofi. A scala globale, l’ossidazione microbica del metano contribuisce alla rimozione di circa il 3-9% del metano dall’atmosfera. Ma l’importanza dei batteri metanotrofi è ancora maggiore in quanto questi ossidano la maggior parte del metano prodotto nel suolo e nel sottosuolo prima che questo raggiunga l’atmosfera. Le condizioni ambientali dei suoli vulcanici e geotermali (ad esempio scarso contenuto in ossigeno, alta temperature, attività protonica, ect.) sono stati da sempre considerati inospitali per i batteri metanotrofi. Tuttavia, di recente è stata dimostrata la presenza di batteri acidofili e termofili appartenenti al phylum dei Verrucomicrobia. Questi organismi sono stati individuati alla Solfatara di Pozzuoli (Italia), ad Hell’s gate (Nuova Zelanda) ed in Kamchatka (Russia). Qui riportiamo l’attività metanotrofa riscontrata nei suoli dell’Isola di Pantelleria (Italia), dell’Isola di Vulcano (Italia), di Sousaki (Grecia), di Nea Kameni- Santorini (Grecia), e dell’Isola di Nisyros (Grecia). Evidenze di rimozione microbica del metano in questi suoli era già stata riscontrata nel rapporto dei flussi di CO2/CH4, che risultava sempre inferiore rispetto a quello atteso, indicando una perdita di CH4 durante il suo movimento verso la superficie. Esperimenti per la misura del consumo di metano sono stati eseguiti usando i suoli di Pantelleria, Vulcano, Nea kameni, Nisyros e Sousaki. Questi esperimenti hanno rivelato tassi di consumo fino a 950, 48, 15, 39 e 520 ng CH4 h-1 per ogni grammo di suolo (peso secco), rispettivamente. Solo pochi campioni non hanno indicato consumo di metano. L’analisi dei gas del suolo e le caratteristiche chimico-fisiche del suolo ci hanno permesso di discriminare i fattori principali che influenzano la presenza dei metanotrofi e il tasso dei consumo del metano. La composizione del gas dal suoli, e in particolare il contenuto di CH4 e di H2S rappresentano il fattore discriminate per i metanotrofi. infatti, l’isola d Vulcano e di Nisyros, il cui contenuto in H2S raggiunge circa 250000 ppm, mostrano i consumi più bassi. In aggiunta nei suoli geotermali e vulcanici l’H2S contribuisce all’abbassamento del pH dei suoli. I valori di consuma maggiori sono stati misurati nell’isola di Pantelleria dove l’H 2S è meno di 20 ppm e il pH è vicino alla neutralità. Analisi microbiologiche e molecolari hanno permesso di riscontrare nei suoli di Pantelleria la presenza di batteri metanotrofi affiliati ai Gamma ed agli Alfa-Proteobatteri ed agli acido-termofili Verrucomicrobia. Il metanotrofo coltivabile appartenete al genere Methylocystis (Alfaproteobatterio) e il Gammaproteobatterio Methylobacterium sono stati isolati attraverso colture di arricchimento. Gli isolati mostrano ampi range di tolleranza di pH e temperatura e un tasso di ossidazione fino a 450 ppm/h. Attraverso l’amplificazione del gene pmoA, basandosi sui metodi coltura-indipendenti è stata rivelata un’ampia diversità di batteri metanotrofi appartenenti ai Proteobatteri (α- e γ-) ed ai Verrucomicrobia. Questo è il primo report in cui si dimostra la coesistenza di entrambi i phyla di metanotrofi in un sito geotermale/vulcanico. La presenza dei metanotrofi Proteobatteri era inaspettata perché le condizioni di sito sono state considerate inadeguate e può essere spiegata del pH non eccessivamente basso (>5) di questo specifico sito geotermale. Queste specie possono aver trovato la loro nicchia negli strati più superficiali dei suoli di Favara Grande a Pantelleria dove le temperature non sono così alte ed è presente una forte risalita di metano. capire l’ecologia dei metanotrofi nei siti geotermali e vulcanici aumenterà le conoscenze nel loro ruolo nelle emissioni di metano in atmosfera.
Yearly, 22 Tg of CH4 are released in to the atmosphere from several natural and anthropogenic sources. Methane plays an important role in the Earth’s atmospheric chemistry and radiative balance being the most important greenhouse gas after carbon dioxide. Volcanic/geothermal areas contribute to the methane flux, being the site of widespread diffuse degassing of endogenous gases. Preliminary studies estimated a total CH4 emission from European geothermal and volcanic systems in the range 4-16 kt a-1. This estimate was obtained indirectly from CO2 or H2O output data and from CO2/CH4 or H2O/CH4 values measured in the main gaseous manifestations. The total estimated CH4 emission from geothermal/volcanic areas is still not well defined since the balance between emission through degassing and consumption through soil microbial oxidation is poorly known. Moreover, methane soil flux measurements are laboratory intensive and very few data have been collected until now in these areas. Such methods, although acceptable to obtain order-of-magnitude estimates, completely disregards possible methane microbial oxidation within the soil carried on by the methanotrophs. At the global scale, microbial oxidation in soils contributes for about 3-9% to the total removal of methane from the atmosphere. But the importance of methanotrophic organisms is even larger because they oxidize the greatest part of the methane produced in the soil and in the subsoil before its emission to the atmosphere. Environmental conditions in the soils of volcanic/geothermal areas (i.e. low oxygen content, high temperature and proton activity, etc.) have long been considered inadequate for methanotrophic microorganisms. But recently, it has been demonstrated that methanotrophic consumption in soils occurs also under such harsh conditions due to the presence of acidophilic and thermophilic Verrucomicrobia. These organisms were found in Italy at the Solfatara at Pozzuol (Italy), at Hell’s Gate (New Zealand) and in Kamchatka (Russia), pointing to a worldwide distribution. Here we report on methane oxidation rate measured in Pantelleria Island (Italy), Vulcano Island (Italy), Sousaki (Greece), Nea Kameni (Santorini) and Nisyros (Greece) soils. Clues of methane microbial oxidation in soils of these areas can be already found in the CH4/CO2 ratio of the flux measurements which is always lower than that of the respective fumarolic manifestations indicating a loss of CH4 during the travel of the gases towards earth’s surface. Laboratory methane consumption experiments made on soils collected at Pantelleria, Vulcano, Nea Kameni, Nysiros and Sousaki revealed for most samples consumption rates up to 950, 48, 15, 39 and 520 ng CH4 h-1 for each gram of soil (dry weight), respectively. Only few soil samples displayed no methane consumption activity. Analysis on soil gases and chemical-physical characteristics of the soils allowed us to discriminate the main factors that influenced the methanotrophs presence and the methane consumption rate. Soil gases composition, and in particular the amount of the CH4 and H2S, represent the main discriminating factor for methanotrophs. In fact, Vulcano and Nisyros Island, whose soil gas contained up to 250000 ppm of H2S, showed the lowest consumption rate. Moreover, in geothermal/volcanic soils H2S contribute to the soil pH lowering; highest methane consumption were recorded in Pantelleria island were H2S is less than 20 ppm and pH close to the neutrality were measured. Microbiological and molecular analyses allowed to detect the presence of methanotrophs affiliated to Gamma and Alpha-Proteobacteria and to the newly discovered acido-thermophilic methanotrophs belong to the Verrucomicrobia phylum in soils from Pantelleria. Culturable methanotrophic Alphaproteobacteria of the genus Methylocystis and the Gammaproteobacteria Methylobacterium were isolated by enrichment cultures. The isolates show a wide range of tolerance to pH and temperatures and an average methane oxidation rate up to 450 ppm/h. A larger diversity of (α- and γ-) proteobacterial and verrucomicrobial methanotrophs was detected by a culture-independent approach based on the amplification of the methane mono-oxygenase gene pmoA. This is the first report describing coexistence of both the methanotrophic phyla (Verrucomicrobia and Protebacteria) in the same geothermal site. The presence of proteobacterial methanoptrophs, in fact, was quite unexpected because they are generally considered not adapted to live in such harsh environments and could be explained by not really low pH values (> 5) of this specific geothermal site. Such species could have found their niches in the shallowest part of the soils of Favara Grande were the temperatures are not so high and thrive on the abundant upraising methane. Understanding the ecology of methanotrophy in geothermal sites will increase our knowledge of their role in methane emissions to the atmosphere.

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Yongprawat, Monthon [Verfasser]. "Hydrochemical and environmental isotope study of the geothermal water in Mae Chan (North) and Ranong (South) geothermal areas in Thailand / Monthon Yongprawat." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2021. http://d-nb.info/1234847132/34.

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Routsolias, Panagiotis. "Energy-efficient design and application of geothermal energy in buildings of areas of protected cultural heritage: Case study Mani, Greece." Thesis, KTH, Byggnadsteknik, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-35069.

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Zhu, Ke [Verfasser], and Philipp [Akademischer Betreuer] Blum. "Urban Heat Island in the Subsurface and Geothermal Potential in Urban Areas / Ke Zhu ; Betreuer: Philipp Blum." Tübingen : Universitätsbibliothek Tübingen, 2013. http://d-nb.info/1163235148/34.

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Tissen, Carolin [Verfasser], and P. [Akademischer Betreuer] Blum. "Increased Groundwater Temperatures and Their Potential for Shallow Geothermal Use in Urban Areas / Carolin Tissen ; Betreuer: P. Blum." Karlsruhe : KIT-Bibliothek, 2020. http://d-nb.info/1216949387/34.

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Taussi, Marco. "Surface exploration and petrological applications in high enthalpy geothermal areas: a multidisciplinary approach for the Cerro Pabellón project (northern Chile)." Doctoral thesis, Urbino, 2019. http://hdl.handle.net/11576/2665629.

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Mitchell, Peter Ashley. "Geology, hydrothermal alteration and geochemistry of the Iamalele (D'Entrecasteaux Islands, Papua New Guinea) and Wairakei (North Island, New Zealand) geothermal areas." Thesis, University of Canterbury. Geology, 1989. http://hdl.handle.net/10092/5561.

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The geothermal system at Iamalele is hosted by a series of late Quaternary high-silica dacite to rhyolite ignimbrite, air-fall tuff and related volcaniclastic rocks. The ignimbrite flows are intercalated with calc-alkalic andesite and low-silica dacite lavas, some of which are high-Mg varieties. The Iamalele Volcanics may be related to caldera collapse and post-caldera volcanism. Geothermal activity occurs over 30 km2 of the Iamalele area. Chemical analyses of water from hot springs indicate that the near-surface reservoir is dominated by an acid-sulphate fluid, and that the deeper reservoir fluid probably has a significant seawater component. Analyses of rock and soil samples within the limits of geothermal activity identified several areas of above background values in Au, Hg, As and Sb. A diamond drill hole was completed to a depth of ~200m in one of these areas. Hydrothermal alteration identified in the drill core indicates that the upper 200 m of the geothermal reservoir is well-zoned and contains a trace element signature characteristic of high-level, epithermal precious metal deposits. With increasing depth mineral assemblages indicative of advanced argillic, intermediate argillic and potassic alteration were observed in the recovered core. The Wairakei geothermal system is hosted by a voluminous sequence of late Quaternary rhyolitic ignimbrite, air fall tuff and related volcaniclastic rocks intercalated with andesite to rhyolite lavas. The volcanic sequence was deposited during formation of the Maroa and Taupo caldera volcanoes, and geothermal activity is localized within a diffuse border zone between these two volcanic centres. The high-temperature reservoir at Wairakei is primarily restricted to porous pyroclastic rocks of the Waiora Formation. Geothermal activity is exposed over ~25 km2 of the Wairakei area. Chemical analyses of well discharge indicate that the fluid is a low salinity, low total sulphur, near-neutral pH chloride water with a local meteoric source. Temperature profiles for ~60% of the Wairakei wells were used to construct a c. 1950 view of the thermal zoning of the reservoir. When compared to the estimated preproduction isotherms, reconnaissance fluid inclusion homogenization temperatures indicated that the deeper portion of the reservoir had cooled by ~45ºC prior to production discharge. Hydrothermal rock alteration within the reservoir is systematically zoned and may be separated into four principal assemblages: propylitic, potassic, intermediate argillic and advanced argillic. Calcium zeolites, mainly wairakite, mordenite and laumontite, occur throughout the reservoir and, with the exception of laumontite, form an integral part of either the propylitic or potassic assemblage. Intermediate argillic alteration is widespread but is not strongly developed. The distribution of advanced argillic alteration is sporadic and restricted to depths less than 65 m. Below a depth of ~500 m potassic alteration commonly overprints propylitic alteration. The location of the "average" Wairakei fluid on several activity diagrams drawn for 100°, 200°, 250° and 300°C indicates that propylitic and potassic alteration probably formed in equilibrium with a hydrothermal fluid chemically equivalent to the modern reservoir fluid at temperatures between ~275° and ~210°C. Assays of drill samples indicate that trace amounts of gold (<0.04 g/t) and other metals permeate the reservoir. Samples of siliceous sinter collected from wellhead production equipment contain significant quantities of precious metals and also platinum group and base metals. Metal-rich scale from a back pressure plate (well 66) was analysed by optical microscopy and by electron microprobe analysis. The scale is composed of several discrete mineral phases which show a distinct paragenesis. Hydrothermal alteration and metallization identified within the reservoirs at Iamalele and Wairakei are similar to hydrothermal alteration and metallization identified within the epithermal precious metal deposits of Rawhide and Round Mountain (Nevada, U.S.A.). The major difference between these systems is the much greater abundance of gold and silver at Rawhide and Round Mountain. Conclusions drawn from these comparisons include: (1) within high-temperature active systems gold remains in solution or is dispersed at low grades; (2) boiling does not appear to be a viable means of producing a gold ore deposit within deep (>500 m) hydrothermal reservoirs and (3) the formation of a major precious metal ore deposit may require the superposition of a structural event on a waning geothermal system to initiate an extended period of fluid mixing. High-Mg lavas similar to ones identified at Iamalele occur elsewhere in the late Cenozoic arc-type volcanic associations of south-eastern Papua New Guinea. Detailed geochemical studies of these rocks have revealed the presence of relatively aphyric lavas which are high in MgO, Cr, and Ni and form an integral part of the arc-type association. The high concentrations of these elements relative to typical arc-related rocks are thought to reflect the chemical composition of the initial melt. High-Mg lavas occur in other volcanic arcs of Papua New Guinea as well as in several other circum-Pacific volcanic arcs, and it is likely that high-Mg lavas form a fundamental component of most, if not all, volcanic arcs.

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Chavarria, Dana, Rubi Ramos, and Carlos Raymundo. "Development of a hybrid heating system based on geothermal–photovoltaic energy to reduce the impact of frosts on inhabitants of rural areas in the ring of fire, southern Peru." Springer Science and Business Media Deutschland GmbH, 2019. http://hdl.handle.net/10757/656249.

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El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado.
The recent climate change has forced people to live in extreme conditions, either excessive heat or cold, implying that they must adapt to survive in these situations. However, there are people who, because of their geographical condition and lack of resources, lack the means and tools to combat these climate changes. The context of this study is provided in a rural town located in the Arequipa region (Peru), whose inhabitants have to fight against frosts of up to −20 °C in an area without electricity. A viable solution to this problem is found through the design and implementation of a heating system using geothermal and photovoltaic energy, which are resources found in the area, according to a report of the Ministry of Energy and Mines. This study analyzes and researches the geographical and meteorological conditions of the region, for validating, through theory and simulations, whether the proposed system can supply the thermal energy required to maintain the indoor temperature at a minimum of 15 °C under extreme conditions. The system is designed after analyzing the best technological options and techniques currently available in the context studied for its ultimate financing and establishing guidelines and indicators for monitoring results.

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Ito, Hisatoshi. "Application of the fission-track dating method to evaluate the thermal history of three geothermal areas, North Kurikoma(Japan), Hijiori(Japan) and Valles caldera(USA)." 京都大学 (Kyoto University), 1996. http://hdl.handle.net/2433/160910.

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本文データは平成22年度国立国会図書館の学位論文(博士)のデジタル化実施により作成された画像ファイルを基にpdf変換したものである
Kyoto University (京都大学)
0048
新制・論文博士
博士(理学)
乙第9151号
論理博第1298号
新制||理||964(附属図書館)
UT51-96-F388
(主査)教授西村進, 教授坂野昇平, 教授瀬戸口烈司
学位規則第4条第2項該当

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GORINI, ANDREA. "Heat source and reservoir of geothermal areas in Latin America as inferred from thermobarometry of amphibole-bearing extrusives and fluid geochemistry: examples from Chile and Ecuador." Doctoral thesis, Urbino, 2017. http://hdl.handle.net/11576/2643905.

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Denbow, Christopher. "Pedagogical development and technical research in the area of geothermal power production." Thesis, KTH, Kraft- och värmeteknologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-55288.

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This work describes the types of power plants used for geothermal power generation in the world; the dry steam power plant, the flash steam power plant and the binary cycle power plant. The objective of the MSc work was the development of learning content on the subject of geothermal power generation for the CompEdu platform in the energy department at KTH. The power plants are described from a system perspective followed by an explanation of the operation of major components. Examples and calculations are given with the aim of illustrating which parameters are most important to the operation of each plant from a performance perspective. An important point is that the report does not go into detail for auxiliary components such as piping and valves. These components are essential from the point of view of fluid handling, however are less important in terms of understanding the mode of operation of the power plant. The power plants must consider the fact that geothermal fluid is corrosive and contains non-condensable gases. The choice of the type of geothermal power plant depends on the temperature and state of the geothermal fluid being utilised (liquid or vapour dominated). The research shows that each power plant has its own significant optimisation criteria, to summarise these: the dry steam power plant uses the selected wellhead pressure for extraction of geothermal fluid to optimise power output, the flash steam power plant uses the operating conditions in the steam separator to optimise power output and the binary cycle uses the required heat exchanger area per unit of power generated to select the optimal working fluid for power generation. Finally, innovative alternatives for power generation from geothermal resources that are on the horizon are introduced.

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Stoch, Agnieszka. "Analysis of Seismic Data Acquired in the Hverahlíð Geothermal Area." Thesis, Uppsala universitet, Geofysik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-413199.

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Volcanic rifting environments, such as in Iceland, are challenging for conventional seismic reflection methods using active surface seismic sources. This study demonstrates the potential of a novel technique, called Virtual Reflection Seismic Profiling (VRSP) for imaging reflections in geothermal regions, like Hverahlíð, where a dense seismic array recorded a number of local microearthquakes for cross-correlation. Uppsala University, in collaboration with Reykjavik Energy, recorded seismicity in Hverahlíð using both seismometers and geophones. Acquired data were processed using the VRSP method, which applies seismic interferometry only to selected events, in this thesis local microearthquakes. Cross-correlation of the signal from a microearthquake recorded at one of the stations, which acts as a virtual source, with a ghost reflection recorded by the remaining receivers, produces a virtual shot gather. Stacking each station’s result, for all available events, and following a conventional multichannel processing sequence resulted in two stacked seismic images. Potential reflections observed in the obtained sections could be associated with major feed zones identified in the area by the borehole measurements. Eight dynamite explosions were processed with a conventional seismic reflection method, as a complementary source to the microearthquakes. In the produced stacked seismic section two potential reflections could be observed. Results from both passive and active datasets were 3D visualised to verify whether the reflections correspond to each other between sections. Two horizons were traced throughout all three stacked sections. One more interface appeared on two images obtained from processing the passive data. This study shows promising results for using natural sources to image the subsurface in a challenging environment.

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Otahal, Joan Marie. "Hydrothermal alteration of basin sediments and the chemical evolution of an extensional geothermal system, Humboldt House Geothermal Area, Pershing County, Nevada." abstract and full text PDF (free order & download UNR users only), 2006. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1438939.

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Mhana, Najwa. "Geothermal Methods : application of time-dependent tomography to detect changes in structure at Long Valley caldera and the Coso geothermal area, California." Thesis, Durham University, 2016. http://etheses.dur.ac.uk/12078/.

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Structural changes in active volcanic and producing geothermal systems are expected because of changes in the distribution of fluids, gases and cracks in the host rocks. Such changes have traditionally been studied using seismic tomography where two independent inversion results are differenced. A new tomography program tomo4d, inverts two epochs simultaneously, imposing constraints to minimize the structural differences calculated between different epochs. This method suppresses spurious changes not required by the data. Both methods were applied to data from Long Valley caldera and the Coso geothermal area, and the results compared. Long Valley caldera, California, has been seismically active since 1978. In particular, a region to the south of the resurgent dome (the “south moat”) and Mammoth Mountain have experienced multiple swarms involving hundreds of thousands of earthquakes. Inverting data from 1997 and 2009/10 using tomo4d detected changes with weaker anomaly strengths compared to those of simul2000A. Some changes imaged using simul2000A are thus not required by the data. Variable changes in Vp, Vs and Vp/Vs were detected and are interpreted as pore pressure decrease and/or drying of minerals, CO2 depletion and flooding during the tectonically active period. The Coso geothermal area, California, is highly seismogenic, with thousands of earthquakes occurring each year. Time-dependent seismic tomography was performed for the years 1996, 2006, 2007, 2008, 2010 and 2012 using both simul2000A and tomo4d. The epochs 1996-2006 and 2007-2012 were studied in detail. During the first epoch, Vp, Vs and Vp/Vs mostly increased in the geothermal field whereas during the second epoch changes were more varied and less extreme. It is concluded that different parts of this tripartite field have different reservoir characteristics, and that operational activities changed with time. These likely involved increasing water saturation in some areas as a result of increased water injection in recent years.

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Gunasekera, Rashmin C. "Induced seismicity and environmental change at The Geysers geothermal area in California." Thesis, Durham University, 2001. http://etheses.dur.ac.uk/3817/.

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Intensive exploitation of the reservoir at The Geysers geothermal area, California, induces myriads of small-magnitude earthquakes that are monitored by a dense, permanent seismometer network that covers most of the reservoir. However, majority of the seismic stations, which belong to the UNOCAL network are poorly calibrated. Station polarities, and sensor orientations for the 8 three-component stations of this network were determined by using accurate focal mechanism solutions from a temporary network and using a simple method of observing the waveform from known earthquake locations. Using data from the UNOCAL network, tomographic inversions were performed for the three-dimensional Vp and Vp/Vs-ratio structure of the reservoir for February 1993, October 1996 and August 1998, adding to the inversions for April 1991 and December 1994 that had already been performed by other investigators. The extensive low -Vp/Vs anomaly known to characterise the reservoir grew progressively in strength from a maximum of 9% to a maximum of 12.4% at sea level during the seven-year study period. The anomaly growth is attributed to the depletion of pore liquid water in the reservoir and its replacement with steam. This causes Vp to decrease by increasing compressibility, and Vs to increase because of the reduction in pore pressure and the drying of argillaceous minerals, e.g., illite, which increases the shear modulus. All these effects serendipitously combine to lower the Vp/Vs ratio, resulting in an exceptionally strong overall effect that provides a convenient tool for monitoring reservoir depletion in the seismogenic zone. Variations in the separate Vp and Vs fields indicate that water depletion was the most important process in the central part of the exploited reservoir, and that pressure reduction and mineral drying were the dominant effects more northwesterly and southeasterly. Relative relocation of micro earthquakes was also performed using the same network. Four regions were studied. Although most multiplets relocated into tighter clusters and the reduction in the RMS of the relative relocations was good, further work is needed to substantiate these initial findings.

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19

St, John Anna Maria. "Hydrogeochemical Characterization of the Alvord Valley Known Geothermal Resources Area, Harney County, Oregon." PDXScholar, 1993. https://pdxscholar.library.pdx.edu/open_access_etds/2678.

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The Alvord Valley Known Geothermal Resources Area (KGRA) , located east of the Steens Mountain-Pueblo Mountains fault block in southeastern Oregon, is within the northern Basin and Range province. This investigation focuses on three thermal areas in the Alvord Basin: Borax Lake and the hot springs north of Borax Lake, Alvord Hot Springs and Mickey Springs. Mickey Springs and the springs north of Borax Lake are boiling at the surface (94 and 95° C, respectively). Inflow temperatures to Borax Lake, measured at a depth of 30 m, are greater than 100° C. Surface temperatures for Alvord Hot Springs and a flowing well northeast of Borax Lake are 78 and 59° C, respectively. Thermal fluids issue from Quaternary lacustrine and alluvial deposits. While silica sinter deposits are present at all three thermal areas, sinter is not presently being deposited. Minor calcite is being deposited at the springs north of Borax Lake. The springs discharge from N to NEstriking, high-angle, basin-bounding faults along the base of Steens Mountain and Mickey Mountain and NE-striking intrabasinal faults south of Alvord Lake. The thermal waters are dilute sodium-bicarbonate waters with significant amounts of sulfate and chloride. Conservative element plots (B, F, and Li vs. Cl) indicate good correlation between Cl and the other conservative elements. These correlations could result from mixing of thermal water with a dilute cold water or fluid evolution due to increased fluid-rock interaction, evaporation, and steam loss due to boiling. The small variations in chloride concentrations of thermal fluids during the sampling period argues against mixing of thermal fluids with cold water. The geothermal system is a hot-water rather than a vapordominated system. The ỎD content of thermal fluids is similar to the ỎD content of local cold water wells, springs, basinal pore fluids at a depth of 4 to 5 m, and perennial streams. Similarities in ỎD values indicate recharge for geothermal fluids is precipitation from the Steens Mountain fault block. The Ỏ18 content of thermal fluids is shifted 2 to 3°/oo to the right of the world meteoric water line indicating fluid-rock interaction at elevated temperatures in the reservoir. Tritium contents indicate relatively long residence times and/or low-velocity circulation of meteoric water through basement rocks. Values range from 0 to 0.25 T.U. The application of two end-member models, which calculate fluid residence times, generate a minimum of 57 years and a maximum of greater than 10,000 years. Estimated reservoir temperatures based on cation and silica geothermometry are between 170 and 200°C. Oxygensulfate isotope geothermometer estimates indicate reservoir temperatures between 198 and 207' C for Borax Lake and Alvord Hot Springs. Mickey Springs and a flowing well northeast of Borax Lake yield temperature estimates of 168 and 150° C, respectively. These values indicate partial reequilibration of the isotopic system. The Ỏ13C contents of carbon dioxide and methane of gas discharges from the thermal areas are similar to geothermal fluids from other sites. The Ỏ13C of methane indicate "normal" geothermal methane for Alvord Hot Springs and Mickey Springs (-27.8 and -27.6, respectively). The Ỏ13C of CH4 for springs north of Borax Lake (-33.6) indicates a small amount of thermogenic methane may be contributed by thermal alteration of organics in basinal sediments. The Ỏ13C contents for C02 at Alvord Hot Springs and Borax Lake are within the range expected for atmospheric, fumarolic, or mantle derived C02 (-6.5 and -6.6, respectively). The Ỏ13C content of C02 from Mickey Springs is isotopically lighter than gas released from fumaroles or the mantle (-9.4). N2/Ar ratios for Mickey Springs and Borax Lake gases (39.2 and 40.8, respectively) indicate interaction with airsaturated ground water during flow through the the zone of aeration. Helium is enriched relative to Ar and N2 in gas discharges from Alvord Hot Springs, indicating longer fluid residence times and/or increased crustal interaction at high temperatures. Ratios of B/Cl indicate the fluid reservoir is hosted in volcanic rocks. The Li/Cs ratios for the Borax Lake thermal area are consistent with a reservoir located in rhyoli tic rocks. The 228Ra/226Ra content of Borax Lake thermal fluids (1.14 ± 0.13 dpm/kg) indicates interaction with volcanic rocks for Borax Lake. The 228Ra/226Ra content of thermal fluids from Alvord Hot Springs and Mickey Springs (0.38~0.02 and 0.17 ~ 0.09) are lower than those expected for volcanic rocks and may indicate local uranium accumulation in the reservoir or zones of upflow. The 87Sr / 86Sr values for thermal waters and stratigraphic uni ts indicate the fluid reservoir is located in volcanic rocks beneath Steens Basalt. Equilibration of fluids in these units argues for thermal water circulation depths of 2 to 2.5 km in the Borax Lake thermal area, greater than 3 km in the Alvord Hot Springs area and 1 to 2 km in the Mickey Springs area. Data presented in this study do not preclude a single large deep reservoir system discharging at these three thermal areas in the Alvord basin. Differences in the chemical and isotopic composition of discharge from the three thermal areas are produced during upf low from the reservoir. During upflow, thermal waters follow a complex pathway of vertical and lateral fractures which includes short residence times in shallow reservoirs before reaching the surface. Boiling, mixing with condensate, oxidation, mixing with 1-3% tritium-bearing, near-surface cold water, relative differences in flow rate and volume, and slow cooling without vigorous boiling are processes that modify fluid composition during upflow from the deep geothermal reservoir.

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20

Rossi, Camilla <1992&gt. "Discrimination between natural and induced seismicity in the Hengill geothermal area, SW Iceland." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amsdottorato.unibo.it/9760/3/rossi_camilla_tesi.pdf.

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The Hengill area is a complex tectonic and geothermal site, located at the triple junction between the Reykjanes Peninsula (RP), the Western Volcanic Zone (WVZ), and the South Iceland Seismic Zone (SISZ). Geothermal systems in the vicinity of the Hengill volcano are exploited for electrical power and heat production, and today the two largest operating geothermal power plants are located at the Nesjavellir and the Hellisheiði. The region is seismically highly active with several thousand earthquakes located yearly, and whose origin may be either natural or anthropogenic. The thesis focuses on the analysis and investigation of the

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21

Barton, David J. "Frequency-magnitude distribution and spatial fractal dimension of seismicity at The Geysers geothermal area and Long Valley Caldera, California." Thesis, Durham University, 1998. http://etheses.dur.ac.uk/5046/.

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Although there is no obvious reason why seismic 6-value and the spatial fractal dimension of earthquakes, D, should be related, there are several reports of observed empirical correlations between these two quantities. In order to investigate this phenomenon, and attempt to relate it to different types of earthquakes, industrially induced seismicity in The Geysers geothermal area, California and earthquake swarms in Long Valley caldera, California were analysed. Raw seismograms from the Unocal-NEC-Thermal network in The Geysers were processed automatically, calculating magnitudes from coda lengths and locating them using a three-dimensional velocity model. Seismicity correlated with the locations of commercial wells and surface fault locations. The entire Geysers dataset was too complex for clear correlations between b, D, seismicity and injection to be observed. In several cases, short pulses of injection induced bursts of seismicity of either small-magnitude, clustered events or large-magnitude diffuse seismicity, resulting always in a transient anomaly of negative b/D. However, sometimes pulses of injection were not accompanied by b/D transients and sometimes b/D transients were not accompanied by known injection. The latter cases may or may not indicate undisclosed injection activity. A seismic crisis in Long Valley caldera was associated with major b/D anomalies that accompanied migration of the activity from a hydrothermal zone on the south edge of the resurgent dome to the right-lateral, blind, near-vertical South Moat fault to the immediate south. The results indicated that the hydrothermal zone is an inhomogeneous structure whereas the South Moat has a mature, coherent fault plane, capable of generating magnitude M = 6 earthquakes and posing a threat to the town of Mammoth Lakes.

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22

Yoshikawa, Miyuki. "Seismic velocity structure beneath Otake-Hatchobaru geothermal area at Kuju Volcano in the central Kyusyu, Japan." 京都大学 (Kyoto University), 2004. http://hdl.handle.net/2433/147827.

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23

Ross, Alwyn C. "The geysers geothermal area, California : tomographic images of the depleted steam reservoir and non-double-couple earthquakes." Thesis, Durham University, 1996. http://etheses.dur.ac.uk/5349/.

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The Geysers geothermal area, California is the world's largest and most intensively exploited steam field, providing about 6% of California's electrical power. The geothermal area is very active seismically, generating about 140 earthquakes per month with M(_D)≥l.2. Non-DC earthquakes have been routinely detected in other geothermal and volcanic areas such as the Hengill-Grensdalur volcanic complex, Iceland but previously went undetected at The Geysers. The steam field is, however, a likely source of non-DC earthquakes because large volumes of steam are extracted and condensate injected during the course of commercial exploitation which might cause cracks or fractures to open and close. Maps of seismic activity through time show conclusively that earthquakes initiate at the onset of production, continue through it and stop when production ceases. Furthermore the volume of steam extracted and/or condensate injected may directly control the rate of seismicity within the geothermal area. A temporary field experiment in April, 1991 recorded about 4000 high-quality earthquakes on three-component digital sensors. Three-dimensional tomographic models of V(_p) and, for the first time at The Geysers, V(_p)/v(_s) were determined using 3906 P-wave and 944 5-wave arrival times from 185 earthquakes. Variations m lithology, temperature and the pore-fluid phase probably produce the variations in V(_p). A strong low in the V(_p)/v(_s) model defines fluid-deficient areas in the steam reservoir and is surrounded by a "halo" of high-V(_p)/v(_s) anomalies. V(_s)/v(_s) can remotely monitor temporal depletion of liquid reserves in the steam reservoir. Well-constrained moment tensor solutions for 30 earthquakes were determined by inverting the polar' ices and amplitude ratios of P- and 5-wave arrivals. Strong evidence for the existence of non-DC earthquakes at The Geysers geothermal area was found. Explosive and implosive events occur in equal numbers and probably reflect source processes involving opening and closing cracks or cavities. The events form a symmetric pattern on source-type plots extending from the postive dipole-to-negative dipole loci, passing through the DC locus. The association with dipole loci rather than crack loci suggests the source process must also involve a compensating flow of fluids, liquid or steam.

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24

Wikström, Maria. "Studie av skyddsavstånd mellan bergvärmeanläggning och skyddsobjekt i ett vattenskyddsområde." Thesis, Uppsala University, Department of Earth Sciences, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-88870.

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During installation and operation of a geothermal heat pump system leakage of an antifreezing agent can appear in a borehole and leak out in surrounding groundwater. To guarantee high quality drinking water for generations to come Sweden has dedicated some areas as water protection areas. The local authority gives permits for the installation of heat pump systems within water protection areas. Before giving a permit the local authority makes an evaluation of the risks involved in installation and operation of the system within the area. By keeping a certain distance between the protected object in the area and the heat pump system the risk of polluting the protected object with an anti-freezing agent can be reduced.

This thesis makes a comparison between three different methods of calculating an appropriate distance between the protected object and the heat pump system. These methods include different numbers of parameters to calculate the appropriate distance.

The results are evaluated with regard to the parameters used. The methods used are a simplified version of an empirical point-count system made by LeGrand, an analytical solution from Baetsle and a numerical solution with Visual MODFLOW 4.0.

Miljöbalken med bakomliggande miljömål skall bidra till att skydda viktiga naturområden för en hållbar utveckling. Ett stort problem för att tillgodose detta behov är dock alla konkurrerande intressen som kan finnas inom ett och samma område.

Vattenskyddsområden utfärdas i syfte att ge tillgång till rent vatten för framtida dricksvatten, men konkurrerande intressen påverkar även dessa områden. Beslut om vilka verksamheter som skall vara tillåtna inom ett vattenskyddsområde tas av den kommun inom vilken området finns.

Ett ökande oljepris har under senare år lett till ett ökat intresse av att installera bergvärmeanläggningar. Denna kraftiga ökning har gjort att negativa effekter av att installera dessa anläggningar förbisetts och att installatörer med dåliga kunskaper fått en chans att etablera sig på marknaden. Före eventuell installation av en bergvärmeanläggning inom ett vattenskyddsområde är det viktigt att beakta de risker som en bergvärmeanläggning kan medföra för omgivande grundvatten. En noggrann utredning kräver beaktande av alla de riskmoment som installation och drift av en sådan anläggning kan medföra. För omgivande grundvatten är det dock främst läckage av köldbärarvätska, dvs. vatten med tillfört frostskyddsmedel, som kan ha en större inverkan. Det finns idag ingen övergripande lagstiftning över tillåtna köldbärarvätskor, men enligt de hänsynsregler som finns i miljöbalken och rekommendationer av bl.a. Sveriges Geologiska Undersökning skall etanol användas som frostskyddsmedel. Etanol för tekniskt bruk innehåller denatureringsmedel för att motverka konsumtion.

Denatureringsmedel samt etanol kan ge smak och lukt till vatten och är därför inte önskvärda att ha i ett vattenskyddsområde. Dessa ämnen tillför även negativa effekter genom att de som substrat för bakterier kan ge en ökad bakteriehalt i marken. Under nedbrytning av dessa ämnen kan även syrefria förhållanden utbildas i jorden vilket kan leda till utfällningar av järn och mangan samt utbildning av svavelväte.

Det finns olika riktlinjer för hur risk med att införa en bergvärmeanläggning i ett vattenskyddsområde beaktas i olika kommuner. Ett lämpligt skyddsavstånd mellan en bergvärmeanläggning och ett skyddsobjekt kan dock göra att risken för att förorena ett skyddsobjekt med etanol kan minimeras. Detta arbete har utförts i syfte att jämföra olika metoder för att ta fram ett skyddsavstånd för en första övergripande undersökning av vilken effekt ett läckage av etanol kan ha på ett skyddsobjekt ett visst avstånd från en ansatt bergvärmeanläggning. De metoder som använts är en förenklad form av en empirisk lösning av LeGrand, en analytisk lösning av Baetsle och en numerisk lösning i Visual MODFLOW.

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25

O'Brien, Jeremy Mark. "Hydrogeochemical Characteristics of the Ngatamariki Geothermal Field and a Comparison with the Orakei Korako Thermal Area, Taupo Volcanic Zone, New Zealand." Thesis, University of Canterbury. Geological Sciences, 2010. http://hdl.handle.net/10092/4097.

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The Ngatamariki Geothermal Field is located 20 km north of Taupo in the Taupo Volcanic Zone and has a boundary of 12 km² as delineated by magneto-telluric surveys (Urzua 2008). Rhyolitic deposits, derived from the Maroa Volcanic Centre, dominate the geology of the area with the 186 AD (Wilson et al. 2009) Taupo pumice mantling stream valleys in the area. The majority of thermal features at Ngatamariki are located along the Orakonui Stream on the western boundary of the field; the stream area is dominated by a 50x30 m geothermal pool filling a hydrothermal eruption crater. This crater was formed during a hydrothermal eruption in 1948, with a subsequent eruption in April 2005. Orakei Korako is located 7 km north of Ngatamariki and has one of the largest collections of thermal features in New Zealand. The geology at Orakei Korako is similar to Ngatamariki, but the area is dominated by a series of south-west trending normal faults which create sinter terraces on the eastern bank of Lake Ohakuri. Water samples from springs and wells at Ngatamariki and Orakei Korako were taken to assess the nature of both fields. Spring waters at Ngatamariki have chloride contents of 56 to 647 mg/l with deep waters from wells ranging from 1183 to 1574 mg/l. This variation is caused by mixing of deep waters with a steam heated groundwater, above clay caps within the reservoir. Stable isotopic results (δ¹⁸O and δD) suggest that reservoir waters are meteoric waters mixed with magmatic (andesitic) water at Ngatamariki. Reservoir water chemistry at Orakei Korako exhibits low chloride contents, which is anomalous in the Taupo Volcanic Zone. Chloride content in well and spring waters is similar ranging from 546 to 147 mg/l, due to mixing of reservoir fluids with a ‘hot water’ diluent at depth. Isotopic compositions of spring waters suggest that they are meteoric waters which mix with magmatic (rhyolitic) water, more enriched in δ¹⁸O and δD than ‘andesitic’ water. Relationships between major ion concentrations and known subsurface geology suggest there is no hydraulic connection between the two fields.

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26

Pollet-Villard, Marion. "Évolution de la surface réactive du feldspath potassique au cours de son altération en contexte géothermal : étude expérimentale et modélisation." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAH015/document.

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L’objectif de cette thèse est de quantifier l’évolution de la surface réactive d’un silicate modèle (orthose) lors de son altération hydrothermale et estimer son impact sur la cinétique réactionnelle. L’étude porte sur : (1) l’influence de la présence de couverture de phases secondaires à même la surface de l’orthose, (2) l’impact de l’anisotropie de la structure cristalline de l’orthose et (3) l’effet de la formation de puits de corrosion en surface. Les résultats expérimentaux et numériques mettent en évidence que la vitesse de dissolution de l’orthose et son évolution au cours du temps dépendent essentiellement de sa morphologie.Certaines faces cristallines se dissolvent 10 fois plus rapidement que d’autres, entraînant une augmentation de la proportion de faces rapides au cours du processus et une élévation, jusqu’à un ordre de grandeur, de la vitesse de dissolution globale de l’orthose. Ces résultats ouvrent d’importantes pistes de réflexion sur la méthode adéquate pour rendre compte des cinétiques des interactions fluide/roche sur le terrain ainsi que sur la signification des lois de vitesse et des mécanismes réactionnels déterminés à partir d’expériences sur poudre
This thesis aims at quantifying the reactive surface area evolution of dissolving K- feldspar, and evaluating the impact on the dissolution kinetics during its alteration in geothermal context. The study focuses on : (1) the influence of secondary coatings on the orthoclase surface, (2) the impact of the anisotropic crystalline structure of orthoclase and (3) the effect of etch pit formation on the mineral surface. Experimental and numerical results highlight that the orthoclase dissolution rate and its evolution over time mainly depends onits morphology. Some orthoclase faces dissolve 10 times faster than others, resulting in an increase of the surface proportion of rapid vs. slow dissolving faces during the process and the increase of up to an order of magnitude of the overall orthoclase dissolution rate. These results question the significance of rate laws and reaction mechanisms determined from powder experiments and the pave to new approaches for investigating mineral reactivity

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27

Fedele, Alessandro <1984&gt. "Continuous geochemical monitoring by mass-spectometer in the Campi Flegrei geothermal area. An application at Pisciarelli-Solfatara (diffuse and fumarolic gases) and at the mud gases during drilling of the CFDDP pilot hole." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5180/1/TESI_DI_DOTTORATO.pdf.

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During this work has been developed an innovative methodology for continuous and in situ gas monitoring (24/24 h) of fumarolic and soil diffusive emissions applied to the geothermal and volcanic area of Pisciarelli near Agnano inside the Campi Flegrei caldera (CFc). In literature there are only scattered and in discrete data of the geochemical gas composition of fumarole at Campi Flegrei; it is only since the early ’80 that exist a systematic record of fumaroles with discrete sampling at Solfatara (Bocca Grande and Bocca Nuova fumaroles) and since 1999, even at the degassing areas of Pisciarelli. This type of sampling has resulted in a time series of geochemical analysis with discontinuous periods of time set (in average 2-3 measurements per month) completely inadequate for the purposes of Civil Defence in such high volcanic risk and densely populated areas. For this purpose, and to remedy this lack of data, during this study was introduced a new methodology of continuous and in situ sampling able to continuously detect data related and from its soil diffusive degassing. Due to its high sampling density (about one measurement per minute therefore producing 1440 data daily) and numerous species detected (CO2, Ar, 36Ar, CH4, He, H2S, N2, O2) allowing a good statistic record and the reconstruction of the gas composition evolution of the investigated area. This methodology is based on continuous sampling of fumaroles gases and soil degassing using an extraction line, which after undergoing a series of condensation processes of the water vapour content - better described hereinafter - is analyzed through using a quadrupole mass spectrometer

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28

Fedele, Alessandro <1984&gt. "Continuous geochemical monitoring by mass-spectometer in the Campi Flegrei geothermal area. An application at Pisciarelli-Solfatara (diffuse and fumarolic gases) and at the mud gases during drilling of the CFDDP pilot hole." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5180/.

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During this work has been developed an innovative methodology for continuous and in situ gas monitoring (24/24 h) of fumarolic and soil diffusive emissions applied to the geothermal and volcanic area of Pisciarelli near Agnano inside the Campi Flegrei caldera (CFc). In literature there are only scattered and in discrete data of the geochemical gas composition of fumarole at Campi Flegrei; it is only since the early ’80 that exist a systematic record of fumaroles with discrete sampling at Solfatara (Bocca Grande and Bocca Nuova fumaroles) and since 1999, even at the degassing areas of Pisciarelli. This type of sampling has resulted in a time series of geochemical analysis with discontinuous periods of time set (in average 2-3 measurements per month) completely inadequate for the purposes of Civil Defence in such high volcanic risk and densely populated areas. For this purpose, and to remedy this lack of data, during this study was introduced a new methodology of continuous and in situ sampling able to continuously detect data related and from its soil diffusive degassing. Due to its high sampling density (about one measurement per minute therefore producing 1440 data daily) and numerous species detected (CO2, Ar, 36Ar, CH4, He, H2S, N2, O2) allowing a good statistic record and the reconstruction of the gas composition evolution of the investigated area. This methodology is based on continuous sampling of fumaroles gases and soil degassing using an extraction line, which after undergoing a series of condensation processes of the water vapour content - better described hereinafter - is analyzed through using a quadrupole mass spectrometer

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29

Reboul, Guillaume. "Metabarcoding and metagenomic approaches to decipher microbial communities in suboxic environments Microbial eukaryotes in the suboxic chemosyn- thetic ecosystem of Movile Cave, Romania Hyper- diverse archaea near life limits at the polyextreme geothermal Dallol area Performance of the melting seawater-ice elution method on the metabarcoding characterization of benthic protist communities Core microbial communities of lacustrine microbialites sampled along an alkalinity gradient Environmental drivers of plankton protist communities along latitudinal and vertical gradients in the oldest and deepest freshwater lake Ancient Adaptive Lateral Gene Transfers in the Symbiotic Opalina-Blastocystis Stramenopile Lineage Marine signature taxa and microbial community stability along latitudinal and vertical gradients in sediments of the deepest freshwater lake." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASL041.

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L’écologie microbienne concerne l’étude des microorganismes et de leurs interactions biotiques et abiotiques dans un écosystème donné. Ces vingt dernières années, l’avancement des techniques moléculaires pour analyser la diversité microbienne et, notamment, les nouvelles technologies de séquençages (NGS) ont permis de surmonter les limitations associées aux approches traditionnelles basées sur la culture et la microscopie. Ces approches moléculaires ont conduit à une accumulation des données de diversité microbienne et de potentiel métabolique dans des communautés microbiennes des écosystèmes variés.Cependant, ces efforts ont été principalement appliqués sur des environnements facilement accessibles ou liés à l’humain, comme le plancton (marin principalement) et la flore intestinale. Néanmoins, ceci a conduit à une très forte augmentation de données environnementales et au développement de la bioinformatique par le biais de nombreux outils. Parmi les environnements délaissés des études, les environnements faibles en oxygène sont probablement également porteurs de nouveautés phylogénique ou métaboliques.Afin de palier à cela, nous avons choisi d’explorer deux environnements suboxiques relativement peu étudiés : la cave Movile (Roumanie) et les sédiments du lac Baikal (Sibérie, Russie). Notre but étant de montrer les diversités phylogénétiques et fonctionnelles des microbes de ces biotopes.Pour cela, j’ai d'abord développé un pipeline d’analyse de données métabarcoding (petite sous-unités ribosomique). Ensuite, j’ai appliqué cet outil sur des données de métabarcoding de protistes provenant d’échantillons d’eau et de tapis microbiens de la cave de Movile, un écosystème chemosynthétique pratiquement fermé. Nous avons montré que la diversité des protistes de la cave s’étendait à quasiment tous les grands groupes eucaryotes et provenait à la fois d’origine d’eaux douces et marines. De plus, la plupart ont été affiliées à des groupes d’organismes typiquement anaérobies, ce qui est concordant avec les paramètres abiotiques de la cave. Écologiquement, ces protistes sont des prédateurs mais aussi vraisemblablement des partenaires symbiotiques avec des espèces procaryotes de la cave.Dans une deuxième étude, j’ai eu l’opportunité d’appliquer ce pipeline de métabarcoding sur des données procaryotes et eucaryotes provenant des couches superficielles des sédiments du lac d’eau douce Baikal. Comme attendu, les communautés microbiennes dans ces sédiments sont particulièrement diverses et relativement enrichis en archées. Nous avons aussi pu mettre en évidence des lignées que l’on pensait exclusivement marines dans ces sédiments. Ces lignées sont probablement planctoniques mais s’accumulent au fond par sédimentation. Enfin, les échantillons ont été prélevés dans le but de tester les influences de la profondeur, du bassin et de la latitude sur les communautés. Aucune d’elles ne s’est révélée significative.Dans une troisième étude, j'ai utilisé une approche métagénomique afin de révéler les acteurs écologiquement majeurs dans les sédiments, leurs rôles et de reconstruire leurs génomes. Cela nous a permis notamment de mettre en évidence le rôle primordial des Thaumarchaeota dans le cycle de l’azote et la production primaire de molécules de carbone. Les chloroflexi et les protéobacteries ont aussi un rôle important dans la surface des sédiments du lac Baikal. Ce travail de thèse participe à la connaissance globale de la diversité microbienne sur la planète en mettant en lumière des environnements peu étudiés. De plus, l’étude de la surface des sédiments du lac Baikal apporte de nouvelles données sur le sujet de la transition eau douces/eau marines des microbes. Enfin, la métagénomique a permis de révéler le cycle des nutriments et les microorganismes y participant dans ces échantillons de sédiment. En résumé, ce travail vient mettre en lumière l’écologie microbienne d’écosystèmes suboxiques, notamment la surface des sédiments du lac Baikal
Microbial ecology is the science of micro-organisms and their biotic and abiotic interactions in a given ecosystem. As technology has advanced, molecular techniques have been widely used to overcome the limitations of classical approaches such as culturing and microscopy. Indeed, the development of Next Generation Sequencing (NGS) technologies in the past twenty years has largely helped to unravel the phylogenetic diversity and functional potential of microbial communities across ecosystems.Nonetheless, most of the environments studied through these techniques concentrated on relatively easily accessible, tractable and host-related ecosystems such as plankton (especially in marine ecosystems), soils and gut microbiomes. This has contributed to the rapid accumulation of a wealth of environmental diversity and metagenomic data along with advances in bioinformatics leading to the development of myriads of tools. Oxygen-depleted environments and especially their microbial eukaryote components are less studied and may lead to future phylogenetic and metabolic discoveries.In order to address this, we conducted analyses on two poorly studied suboxic ecosystems: Movile Cave (Romania) and lake Baikal sediments (Siberia, Russia). In this task, we aimed at unveiling the taxonomic and functional diversity of microorganims in these environments.To do so, I first evaluated the available bioinformatics tools and implemented a bioinformatics pipeline for 16S/18S rRNA gene-based metabarcoding analysis, making reasoned methodological choices. Then, as a case study, I carried out metabarcoding analyses of the water and floating microbial mats found in Movile Cave in order to investigate its protist diversity. Our study showed that Movile Cave, a sealed off chemosynthetic ecosystem, harbored a substantial protist diversity with species spanning most of the major eukaryotic super groups. The majority if these protists were related to species of freshwater and marine origins. Most of them were putatively anaerobic, in line with the cave environment, and suggesting that in addition to their predatory role, they might participate in prokaryote-protist symbioses.In a second study, I applied my metabarcoding pipeline to explore unique and relatively unexplored environment of Lake Baikal sediments. I first applied a metabarcoding approach using 16S and 18S rRNA genes to describe prokaryotic as well as protist diversity. Overall, the communities within these ecosystems were very diverse and enriched in ammonia-oxidizing Thaumarchaeota. We also identified several typical marine taxa which are likely planktonic but accumulate in sediments. Finally, our sampling plan allowed us to test whether differences across depth, basin or latitude affected microbial community structure. Our results showed that the composition of sediment microbial communities remained relatively stable across the samples regardless of depth or latitude.In a third study, we applied metagenomics to study the metabolic potential of communities associated to Baikal sediments and to reconstruct metagenome-assembled genomes (MAGs) of dominant organisms. This revealed the considerable ecological importance of Thaumarchaeota lineages in lake Baikal sediments, which were found to be the major autotrophic phyla and also very implicated in the nitrogen cycle. Chloroflexi and Proteobacteria-related species also appeared ecologically important.This PhD thesis reveals the taxonomic diversity of poorly studied suboxic ecosystems and therefore contributes to our knowledge of microbial diversity on Earth. Additionally, the analyses of surface sediment samples in lake Baikal adds new light on freshwater-marine transitions. The metagenomic analyses reported here allowed us to postulate a model of nutrient cycle carried out by microorganismsin these sediments. Overall, this work sheds light on the microbial ecology of oxygen-depleted environments, and most notably lake Baikal surface sediments

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30

Chen, Mao-Yen, and 陳懋彥. "Thermophilic Bacteria in Geothermal Areas of Taiwan." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/04789017293474892737.

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博士
國立臺灣大學
植物學研究所
90
Abstract Taiwan is a small island located in the circum-Pacific volcanic zone. Geothermal environments with different characteristics are widely distributed in different areas on this island. Until 1995, there were about 127 named hot springs discovered in Taiwan. It should be many thermophilic microorganisms in those hot springs. In this study, 22 hot springs in Taiwan geothermal areas were investigated since 1998 summer. Geographic data of these geothermal areas were also collected and analyzed. In geographic studies, neutral and alkaline hot springs play the major part in various geothermal environments of Taiwan. On the isolation of thermophilic microorganisms, 520 thermophilic bacteria were purified and studied. They are classified into two groups: Gram positive bacteria including Bacillus sp., Geobacillus sp., Alicyclobacillus sp., Sulfobacillus sp., Deinococcus sp., Rubrobacter sp., Paracraurococcus sp.; as well as Gram negative bacteria including Thermus sp., Meiothermus sp., Rhodothermus sp., Chloroflexus sp., Roseiflexus sp., Thermonema sp. and Pseudoxthanomonas sp.. Many specific isolates were studied and two species- Meiothermus taiwanensis and Pseudoxanthomonas taiwanensis were published on IJSEM as new species. From ecological view, changes of biodiversity by contrived interruption were also observed in Wu-rai areas. Finally, an indigenous Germplasms of thermophilic bacteria were established during this study. It has been proved that the microbial biodiversity of geothermal areas of Taiwan is abundant, and more advanced studies including basic research and applications of these isolates were worth to be processed. Although there are many excellent geothermal areas in Taiwan, more and more hot springs were disappeared by earthquakes and contrived interruption, and thermophilic microbes were disappeared during these changes. It is urgent to study the diverse thermophilic microbes in geothermal areas of Taiwan under systematic investigation.

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31

Hsu, Chia-Ju, and 許嘉如. "Studies of Radioresistant Thermophilic Bacteria from Geothermal Areas in Taiwan." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/88521955929237910911.

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碩士
國立臺灣大學
植物科學研究所
93
There are many different kinds of thermophilic bacteria living in the geothermal environment around Taiwan. According to the phylogenetic analysis, the well documented radiation resistant Deinococcus radiodurans and thermophilic bacteria Thermus spp. may come from same ancestor. Several thermophilic bacteria with extremely gamma-radiation resistance had been reported from hot spring environment recently. The objective of this study is to investigate thermophilic bacteria also carrying radio-resistant ability from hot springs in Taiwan. Two hundred and three thermophiles were isolated from 72 hot springs in Taiwan after gamma radiation treatment of the samples. According to 16S rDNA sequence analysis, these isolates were grouped into 7 genera: Deioncoccus spp., Rubrobacter spp., Meiothermus spp., Bacillus spp., Aneurinibacillus spp., Anoxybacillus spp. and Paenibacillus spp. Twenty strains were selected for further studies. Besides the morphological, biochemical and genetic analyses of these twenty isolates, the stress conditions including γ and UV radiation, heavy metal ﹝Cd(NO3)2 & HgCl2﹞ as well as hydrogen peroxide treatment are also determined. The results showed that most of the isolates were extremely resistant to γ-radiation, UV light as well as hydrogen peroxide. However, there are no evidence to show that these thermophilic radioresistant bacteria also have the ability to resistant heavy metal. This is the first report that Meiothermus spp., Aneurinibacillus spp., Anoxybacillus spp. and Paenibacillus spp. have the ability to resist radiation.

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32

Tsai, Hsin-Lun, and 蔡欣倫. "Studies on Radiation Resistant Rubrobacter spp.from geothermal areas in Taiwan." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/28357447895293362993.

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碩士
國立臺灣大學
植物科學研究所
95
In the previous studies, several genera of thermophilic bacteria with radiation resistance were isolated from geothermal environments in Taiwan by our laboratory. Though Rubrobacter spp. exhibited extreme radiation resistance, but only a few species had been isolated and studied. According to 16 S rRNA gene sequence analysis, 32 strains of thermophiles belong to genus Rubrobacter were isolated and partially characterized from ten geothermal areas in Taiwan. In this study, we focus on two groups containing six isolates that had the potential to be new species in genus Rubrobacter for further characterization and identification. These new isolates were Gram positive thermophiles with the ability to resist radiation. According to genetic, morphological, physiological and biochemical properties, group 1 isolates NTU-806, NTU-807, and NTU-808 from Danda were identified as R. taiwanensis. Group 2 isolates NTU-829, NTU-1106, and NTU-1119 showed 94 % 16S rRNA gene sequence similarities and 26-29% DNA-DNA similarities to R. radiotolerans. These three isolates grew optimally at 50 oC, and in the medium containing 0-7 % (w/v) NaCl, while R. radiotolerans at 45 oC and 0-3% NaCl. The new isolates from group 2 contained higher amount of 18:0 anteiso and 19:0 anteiso fatty acids than R. radiotolerans. Based on DNA homology, 16S rRNA gene sequence, as well as physiological and biochemical analyses, strains NTU-829, NTU-1106, and NTU-1119 could be identified as a novel species of genus Rubrobacter.

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Tsai, Hsin-Lun. "Studies on Radiation Resistant Rubrobacter spp. from geothermal areas in Taiwan." 2007. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-2207200700173200.

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34

Li, Shih-shuan, and 李世軒. "Studies on Novel ThermotolerantExiguobacterium sp. Isolated from Geothermal Areas of Lutao, Taiwan." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/28275406637637044115.

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碩士
輔仁大學
生命科學系碩士班
94
There are many geothermal areas which include variable microorganisms in Taiwan. The study is aimed to isolate the thermophiles from the sample of warm sea water located on Lyudao Township, Taitung County. According to the results of 16S rDNA sequences analyses, four isolates, NTU-1329, NTU-1330, NTU1331, and NTU-1337 were selected for further investigation. Colonies are 2-3 mm in diameter after incubation for 2 days on modified Thermus agar at 40 oC and yellow-orange convex with entire margin and glossy. Cells are Gram positive, non-spore forming, motile with peritrichous flagella. Cells are short rods (0.73 μm x 1.23 μm) in the early stationary phase. Growth occurs at 30 oC and 50 oC, with optimal growth at 30 oC. The optimal pH for growth is pH 7-11 and growth does not occur in the presence of 16 % NaCl. All strains hydrolyze skim milk and starch. They show alkaline phosphatase, esterase, leucine arylamidase, acid phosphatase, α-glucosidase, β-glucosidase, catalase and oxidase activity. All strains utilize citrate, D-mannose, D-xylose, L-glutamate, malate, pyruvic acid, L-proline, L-alaline and L-ornithine. Major fatty acids are C16:0, isoC16:0, C18:0 and anteisoC17:0 . The 16S rDNA sequence similarities of NTU-1329, NTU-1330, NTU1331, and NTU-1337 to Exiguobacterium aestuarii are between 97.9 ~ 98.6 %. The DNA G+C contents of the isolates are between 60.3 ~ 62.9 %. On the basis of morphological, physiological and genetic data, there are differences between the four strains and E. aestuarii. It is found oxidase-negative and no hydrolysis of starch in E. aestuarii but not in four strains. The maximal growth temperature and pH of four strains are the highest in the genus of Exiguobacterium. As a result, the four strains might be a novel species in the genus of Exiguobacterium.

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35

Chao, Kuan-chen, and 趙冠辰. "Studies on Novel Thermophilic Pseudoxanthomonas-related Proteobacteria Isolatedfrom Geothermal Areas in Taiwan." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/48074552216882452090.

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碩士
輔仁大學
生命科學系碩士班
94
This study is aimed to research the thermophile from hot springs in Taiwan. One yellow pigmented organism with growth temperature around 50 oC, was isolated from hot springs named Shang-Li in Taitung. According to the resμlt of 16S rDNA sequence analysis, the strain showed 94.5 % to Thermomonas haemolytica A50-7-3T and 94.2 % sequence similarity to Pseudoxanthomonas taiwanensis CB-226T and Lysobacter gummosus LMG 8763T. There are differences between the strain NTU-1589 and type strains on morphological observation, physiological, biochemical and genetic analyses. The strain was gram-negative rods and had a polar flagellum. Growth occurs between 30 oC and 50 oC, with optimal temperature at 50 oC. The pH range for growth was 6-10, with an optimal at pH 8. Growth does not occur in modified thermus plate contain 2 % NaCl. The isolate can utilize D-Galactose, D-Melibiose and myo-Inositol, and have α-glucosidase and elastase activities. The major composition of fatty acids are C16:0, C16:0 iso and C18:0. It is resistant to polymyxin B. The DNA G+C contain is 68.7 mol %. Based on these differences and phylogenic tree, the strain NTU-1589 coμld be considered as novel species related to the genus of Pseudoxanthomonas.

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36

Shi, Yeu-Ching, and 時雨青. "Study of novel theremophilic silanimonas-like proteobacteria isolated from geothermal areas in Taiwna." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/65644980644087608831.

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碩士
國立臺灣大學
植物科學研究所
93
Six pale yellow-pigmented organisms with optimal growth temperature around 50 oC, were isolated from hot springs in Taiwan. These strains were motile with single polar flagellum, non-spore forming, alkaliphilic, gram-negative rods. The G+C contents (mol %) of these isolates were ranged from 68.7 to 73.3. Phylogenetic analysis of the 16S rDNA and physiological, biochemical studies showed that these isolated can be classified into two groups. Group Ⅰ including isolates NTU-1000, NTU-1555 and NTU-1310 showed 99.6 % to 99.8 % sequences similarity to Silanimonas lenta 25-4T. All these strains can hydrolyze starch. The pH range for growth was 7.0-12.0, with an optimal at pH 9.0. Strains NTU-1000, NTU-1310, NTU-1555 and S. lenta 25-4T can grow in nutrient broth containing 1 % NaCl. Fructose was utilized by strains of Group Ⅰ and Silanimonas lenta 25-4T. NTU-1000, NTU-1310, NTU-1555 and S. lenta 25-4T produced the following enzymes: alkaline phosphatase; esterase(C4); esteraselipase(C8); lipase(C14); leucine arylamidase; trypsin; a-chymotypsin; acid phosphatase; Naphthol-AS-BI-phosphohydrolase. Group Ⅱ including isolates NTU-1133, NTU-1197 and NTU-1358 showed 94.8 % to 95.0 % sequences similarity to S. lenta 25-4T. Different from S. lenta 25-4T that hydrolysis of starch was not observed by these strains. Isolates NTU-1133 and NTU-1197 could grow in nutrient broth containing 2 % NaCl, however NTU-1358 and S. lenta 25-4T could grow at salt concentrations up to 3 %. Strain NTU-1133 and S. lenta 25-4T could assimilate cellobiose and D-glucose, however NTU-1197, NTU-1358 could not. Strain NTU-1197 could utilize mannitol; strain NTU-1133 could utilize raffinose and trehalose, but S. lenta 25-4T could not use these carbohydrates. Strains NTU-1133, NTU-1197, NTU-1358 and S. lenta 25-4T produced the following enzymes: alkaline phosphatase; esterase (C4); esteraselipase (C8); leucine arylamidas; trypsin; a-chymotypsin; acid phosphatase; Naphthol-AS-BI-phosphohydrolase. Differences in the characteristics of the strains were as follows: valine arylamidase and cystine arylamidase were positive in NTU-1133, NTU-1197, NTU1358 and a-glucosidase in NTU-1358. The major cellular fatty acids of NTU-1133, NTU-1197 and NTU1358 were 15:0 iso, 16:0 iso and 17:0 iso. 16:0 fatty acids were detected in the strains of Group Ⅱ but not in S. lenta 25-4T. Based on the DNA-DNA hybridization (low than 70 %) and the divergence in 16S rDNA (higher than 3 %). These three isolates (NTU-1133, NTU-1197, NTU1358) could be considered as new species of Silanimonas.

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37

HUANG, CHUN-FA, and 黃俊發. "The Alteration Mineral Assemblages and Its Implication in Tuchang- Chingshui Geothermal Field Areas." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/xx86w6.

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碩士
中國文化大學
地學研究所地質組
107
The exploration of geothermal resource in Taiwan can be traced back to the 1970s. A 3-MWe geothermal energy power plant was installed in Chingshui Geothermal Field, Ilan of Taiwan in 1981. The geothermal energy power plant of Chingshui Geothermal Field is one of few geothermal fields of low grade metamorphic rock in the world. The majority of bedrocks are argillites, slate and meta-sandstone. We have systematically analyzed samples taken in Tuchang-Chingshui Geothermal field, of the region to understand the spatial distribution of mineral assemblages under the influence of alterations by using XRD. The recognition of alteration mineral zoning can help identify hydrothermal fluid channel ways. We have found the existence of smectite and mix-layer of clay minerals, a typical product of hydrothermal alteration. It could further provide the linkage between mineral assemblages with geothermal activities and could be served as indicators, particularly in low grade metamorphic regions.

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38

Wen, Hsin-Yi, and 溫心怡. "Soil Carbon Dioxide Flux in Geothermal Areas of the Tatun Volcano Group, Northern Taiwan." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/28205915007050625390.

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碩士
臺灣大學
地質科學研究所
98
Carbon dioxide is, after water vapor, the most abundant gas dissolved in magma. CO2 was discharged into atmosphere from not only craters but also volcanic area soil; moreover, CO2 and volcanic activity are in close correlation. Thus, the soil CO2 flux variation in volcanic area has been considered as a useful tool to investigate the volcanic activity in a safe distance. In this work, we have measured the soil CO2 flux in representative geothermal areas of Tatun Volcano Group (TVG) and further discuss its spatial and temporal variations. In this study we measured the soil CO2 flux in the representative areas of TVG by closed-chamber method. Soil CO2 flux can be obtained ca. 537 g m-2 day-1 at Geng-tze-ping (GTP), ca. 122 g m-2 day-1 at Da-you-keng (DYK), ca. 425 g m-2 day-1 at She-haung-ping and ca. 24.6 g m-2 day-1 at Tatun Natural Park, respectively. The results show that the emission flux of soil CO2 at DYK is much lower than the value of GTP and LHK. It could be explained that most CO2 gas can be released to the surface through the highly permeable conduit/pathway (fumaroles) at DYK and hence, less emission flux of soil CO2 can be observed. Furthermore, we can estimate the total amount of 113 t day-1 of soil CO2 in the geothermal area of TVG. It is close to the values from other active geothermal areas in the world. The Hsiao-You-Keng (SYK) area was chosen for continuous monitoring of soil CO2 flux. The station, located about 50 meters away from the major fumaroles, is equipped with two CO2 sensors covered and protected with plastic box, and then can be used for long term monitoring under corrosive environments. The system has continuously worked from 2008/6/20 until recent; during the monitoring period, the soil CO2 flux is from ca. 0.012 to 2130 g m-2 day-1. The results of soil CO2 flux showed significant variations and also closely related to local rainfall. The flux apparently reduced after heavy rainfall. This may be explained by the decrease of the soil permeability, and consequently blocked the degassing pathways, due to the heavy rain. However, there is no clear relationship between the flux variation and earthquake activities observed from our data so far. For better monitoring the potential magmatic activity of TVG, another monitoring station was just setup at GTP in 2009.

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39

Caponi, Chiara. "Behaviour of S-bearing compounds (H2S and SO2) emitted in air from natural emissions in hydrothermal-volcanic systems." Doctoral thesis, 2019. http://hdl.handle.net/2158/1154029.

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The main sources of SO2 and H2S in air consist of (i) natural fluid emissions from active/quiescent volcanoes and (ii) anthropogenic activities. These gas compounds have a strong impact on air quality, since they are toxic and cli- mate forcing agents. Notwithstanding, the behaviour of these S-compounds in air is poorly known, since relatively scarce are the available thermody- namic data as well as those deriving from direct measurements. Hydro- gen sulphide is the main S-compounds of low-temperature emissions in hy- drothermal systems and, in the atmosphere, tends to be oxidized to SO2 by photochemical reactions. Oxidation processes are also affecting atmospheric SO2, which is the main S-compounds of high-temperature emissions in vol- canic systems, since about 65% is transformed to SO42− whilst the remaining 35% is removed by dry deposition. This PhD research project was aimed to provide insights into the chemical-physical processes affecting H2S and SO2 in plumes discharged from hydrothermal fluid emissions which con- trol the spatial distribution of these gases in air. The empirical approach carried out in Iceland, where a number of hydrothermal emissions related to different volcanic/geothermal systems occurs, followed a measurement strategy optimized during two first field campaign at Vulcano Island (Aeo- lian Archipelago) and at La Solfatara (Phlegrean Fields). Hydrogen sulphide and SO2 measurements in air were performed using a Thermo Scientific 450i Analyzer positioned at increasing distance along patterns downwind from the emission sources, in order to obtain a “snapshot” of the H2S and SO2 concentrations within the plume. A mathematical model of the spatial dis- tribution of the two air pollutants, coupled with a statistical elaboration of the measured data, was applied to the measured data to i) describe the evo- lution of H2S and SO2 within the plume with distance observed in the field, ii) determine the rate of loss of H2S and SO2 at increasing distances from the source, and iii) discriminate the effects of physical (i.e. dilution) and chem- ical (e.g., oxidation of H2S to SO2) mechanisms controlling the spatial and temporal dispersion of the S-bearing gases. The results show that dilution by air affect both H2S and SO2 at a lower extent with respect to the chemi- cal degradation processes. Simulations carried out using the mathematical model show that, at distances >100 meters from the emitting source, the H2S and SO2 concentrations were below (<5 ppb by vol.) those of the guidelines of WHO (World Health Organization). Remarkably, the reaction rates of ox- idation processes (i.e. homogeneous gas-phase reactions via OH radical) in air for both H2S and SO2 calculated by the model are faster than those sug- gested in literature. This implies that the H2S and SO2 removal mechanism from the plume mostly consist of heterogenous and multiphase reactions that, on their turn, depends on different variables, e.g., presence of water droplets and plume temperature. Different SO2/H2S ratios were measured at each geothermal system, as well as at the same system in the proximity of different gas emissions, suggesting that these SO2/H2S variations were not related to the deep magmatic source, but, more likely, to secondary shallow processes.

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Liou, Yu-Lun, and 劉昱侖. "Geothermal prototype-Lushan Hot Spring Scenic Area Geothermal Resource Integration Center." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/91156379446688738478.

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碩士
朝陽科技大學
建築及都市設計研究所
98
After Typhoon Sinlaku, disaster occurred in Lushan Hot springs became the tipping on many issues, climate anomalies caused by global warming,elimination of the hillside vegetation, occupation of the riverbed, all became the first level of problem, when government and people begin to aware of the previous action has resulted the finance and even the trouble relate to human lives, The local form of using the land and resource has got to go through a revolution. Under the guidance of the government, dangerous riverbed area has to be abandoned, return the land to the original aspect of the nature itself. They also chose a more secure location to put in the investment. In this new land of hot springs, there are many practices will take place as a response to the previous lands use failures﹒ This context reviews the root of the cause of the problems in the past, for example the way of using the resource causing the climate anomaly, the safety issues came along with the lands being inappropriately developed, environmental issues, the most obvious,immethodicall installed Hot spring facilities damaging the landscape and its looking, etc. Studying and finding the basic strengths of the land itself, for example the abundance of the hot spring resource and other touring vales. While resolving the problems, make the use of the land''s strength the biggest output. Secondly, base on the research data, pinpoint the application of hot spring resource, touring and environment buffering, widely gather all kinds of operating techniques and historical cases, seek for the possibility of any plans, then gather, integrate them. Through the establish of the concept and the resource management plan. Sort out the statistics of the hot spring''s capacity, street''s view, land scape, environmental tour plan (Lushan Hot Spring Scenic Area Geothermal Resource Integration Center ) as a important and influential index of the new area development. Lastly, according to the planned policies and techniques, fulfill them on the design of the entire construction, bring out a brand new constructions and ways on the resource application and the lands development. Also bring out a support plan and space structure for the new hot spring touring. Outline the initial picture of the area''s street view, expecting when developing the hot spring industry can also cover the environmental issues. Avoiding the repeat of yesterday''s mistake.

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41

Irwan and 英萬. "Magnetotelluric Imaging Improves Understanding of Geothermal System: Case in Chingshui Geothermal Area, Northeastern Taiwan." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/29973936299848728639.

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碩士
國立中央大學
地球物理研究所
100
The well known geothermal field in Taiwan is Chingshui geothermal area (CGA). The existence of a shallow (~2km) intrusive igneous rock results in a high heat flow and geothermal gradient. The NE deep fault system within the meta-sandstones provides meteoric recharge from a higher elevation to artesianally drive the geothermal system. This study reprocess the 2D modeling and inversion of CGA MT data. The result (Fig. 5.2) shows that anomalously conductive (3-100 ?m) zones, C1 and C2, obtained along the Chingshui fault may represent the geothermal reservoir in this area and the cap formed by clay mineral on top of it. Chingshui fault may act as a main conduit for fluid migration toward the surface. Meanwhile, the high resistivity (300-1000 ?m) host rock, with high temperature gradient and fracture dominated (seismicity indicated) (R2), together with the magma intrusion nearby (R1) represent the possible heat source of CGA. The most interesting feature of this study is the finding of another deeper conductor (C3). C3 conductor is at about 5 km beneath the shallow conductor C1 and C2. All conductors (C1, C2 and C3) in CGA are connected each other by Chingshui fault. However, C3 conductor is most probably the highest potential for enhanced or engineered geothermal system (EGS) in CGA as it owns regional, rather local, enhanced hear and fluid. MT sounding technique, by joint interpretation with geology, geophysical and geochemical information does improve understanding of the geothermal system.

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42

Hou, Ya-Jan, and 侯雅甄. "Study on Ambient Air Hydrogen Sulfide Levels in Petou Geothermal Area." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/16661582849239067848.

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碩士
國立陽明大學
公共衛生研究所
87
The purposes of this study were to investigate the ambient air concentrations of hydrogen sulfide in Petou geothermal area, and to examine the seasonal and temperal fluctuations of ambient air concentrations of hydrogen sulfide. This study was carried out in Longfenqku, Liuhuangku, Yang-Ming University, and hot spring bathroom. 341 ambient air samples were collected from 9 sampling sites. Hydrogen sulfide was aspirated to a midget impinger containing absortant solution and analysed by spectrophotometric method. The results showed that the ambient air concentrations of hydrogen sulfide ranged from undetectable to 2.42mg/m3 in Petou geothermal area. 88% of ambient air samples exceeded the national environmental air quality standard（0.1ppm）. The ambient air concentrations of hydrogen sulfide ranged from undetectable to 2.42mg/m3, undetectable to 1.923mg/m3, undetectable to 2.42mg/m3, 0.008 mg/m3 to 0.935mg/m3 in Longfenqku, Liuhuangku , Yang-Ming University , respectively. The ambient air concentrations of hydrogen sulfide had no statistical difference between day and night significantly. The indoor air concentrations of hydrogen sulfide were in the range of 0.057 mg/m3 to 22.363mg/m3 in hot spring bathroom. Among them, 8% exceeded 15ppm, short-term exposure limit of US/OSHA.

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43

Wei, Ting-Shyang, and 魏廷翔. "Studies of biodiversity of genus Thermus in geothermal area in Taiwan." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/13156431398231592687.

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碩士
國立臺灣大學
植物科學研究所
94
This study focuses on thermophiles isolated from geothermal area in Taiwan. A group of thermophiles similar to genus Thermus which have been isolated from 13 hot springs in Taiwan. They form yellow pigmented colony and the cells of these organisms are Gram-negative, rod-shaped, non-motile, non-spore forming, and can grow at 70 oC. After 16S rDNA amplifications and sequence analyses, the blasting results indicate that these thermophiles can be divided into two groups. The 16S rDNA sequences of the first group isolates exhibit highest similarity value ( above 99 % ) to the related Thermus species. Based on physiological tests and fatty acid analyses, these thermophiles similar to Thermus species which have been named and published formally, are belonged to T. aquaticus NTU-103, T. thermophilus NTU-1534 and NTU-1651；T. oshimai NTU-58、NTU-63 and NTU-88；T. brockianus NTU-9、NTU-153 and NTU-154。 The 16S rDNA similarity of the other group of isolates are between 96% to 98% and DNA-DNA hybridizations are below 70 %. Based on physiological tests, fatty acid analyses, biochemical assays and genetics analyses, these thermophiles may be new species of genus Thermus. T. thermophilus HB8 related isolates NTU-56, NTU-62 and NTU-158 are named T. taipeiensis; T. scotoductus ITI-252 related Isolate NTU-24 is named T. wuariensis; another isolates NTU-559, NTU-1307 and NTU-1597 which are similar to T. brockainus YS038 have not been named. In this study, hundred strains of genus Thermus had been isolated and identified: four species of genus Thermus which are named and published formally are T. aquaticus, T. oshimai, T. brockianus and T. thermophilus, and three new species including T. taipeiensis, T. wuariensis and unnamed Thermus sp. are found in geothermal area of Taiwan. Besides, T. taiwanensis is one of new species of Thermus that is identified but not published formally. Thus, the genus Thermus exists in neutral or slightly alkaline hot springs in Taiwan and shows biodiversity.

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44

Liu, Han-Fang, and 劉瀚方. "A Study of Microseismicity and Traveltime Tomography in the Chingshui Geothermal Area." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/82952130831328207807.

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碩士
國立臺灣大學
地質科學研究所
101
The Chingshui geothermal field was once the largest existing productive geothermal area in Taiwan. Following the restarting of the Chingshui geothermal exploration in recent years, the National Taiwan University Temporary Seismic Network (NTUTSN) was set around the Chingshui geothermal area from 2010 to 2011. After manual picking and earthquake locating, we merged and relocated the catalogs from NTUTSN catalog with the Central Weather Bureau Seismic Network (CWBSN). The microearthquake group beneath the Chingshui geothermal area distributed on the direction of NE with depth of 3 to 7 km and plunged to the NE. Most of the microearthquakes are bounded in between the C-fault and the Xiaonanao fault. In addition, they are in a low resistivity zone, which was inferred as a geothermal reservoir from the magnetotelluric studies. Through the improvement of the catalog quality, the distribution of the microearthquake group can be associated with previous geophysical observations. We also obtained seismic traveltime tomography results through the Local Earthquake Tomography Software (LOTOS) in the Chingshui geothermal area (121.56°-121.76°E, 24.53°-24.73°N), using a total of 4139 arrivals from 368 events. Both P- and S-arrivals are included for velocity inversion. The results show that the microearthquake group was in a region with high Vp/Vs ratio at the depth of 3 to 5 km. It may indicate existence of a fluid-filled fractured matrix forming a deeper geothermal reservoir. Besides, the orientations of the high Vp/Vs ratio structures are ENE-WSW and NW-SE, which correspond to the trends of the Chingshuihsi fault and Xiaonanao fault, respectively. At the cross of the two faults, a high Vp/Vs ratio is obtained. It might be associated with the most fractured region. These fracture zones might serve as conduits for the geothermal activity, and geothermal fluid could circulate within the two fault zones.

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45

Sun, Tien-Hsiang, and 孫天祥. "Study of Stress State around the Chinshui Geothermal District of Ilan Area, Taiwan." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/42334580630745948613.

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碩士
國立臺灣師範大學
地球科學系
102
In order to relieve the dependence on fossil fuels and reduce the production of carbonate-dioxide, the development of neo-energy is not only one of the best ways to work out but also the latest trends in the world. Among all the neo-energy sources, geothermal power plant is a well-developed technique. Chinshui geothermal district, Ilan, Taiwan has been known as one of famous geothermal districts for decades. Some preliminary research shows that there is a huge geothermal reservoir right below Chinshui, Ilan. It would be a great help to the energy policy if the efficient geothermal power plant could be set up here. Understanding fluid conduit fractures is the key to develop geothermal power plants and further Enhanced Geothermal System (EGS). Assessing stress-state (both paleo &; in-situ stress) helps out evaluating history evolution of stress states. Base on in-situ stress state in addition to fracture orientation, the passage or barrier of various fractures can be determined. Chinshui, Ilan locates in the western slate belt of Backbone Range, NE Taiwan. The variation of stress state here is quite complicated since the complex tectonic history of NE Taiwan resulted from collision to back-arc extension. In this work, multi methods were applied to find out the stress states around Chinshui, Ilan. In order to evaluate paleo-stress states, analysis of heterogeneous fault-slipdata such as slickenside and quartz and calcite steps collected from outcrop along 10 km-long Chinshui area. Results show that at least three stages of stress state can be determined. On the other side, to know in-situ stress state, Anelastic Strain Recovery (ASR) method, a core-based method, was applied on the core retrieved form a latest drilling bore-hole of IC-21. Results show that NE-compression and NW-extension of strike-slip faulting stress regime with a low stress ratio. This result consisted with the youngest stage of stress state inferred from fault-slip analysis, impling that this strike-slip stress regime is the in-situ stress throughout the Chinshui geothermal district, Ilan.

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46

Kun-TaLin and 林琨達. "Numerical modeling of geothermal potential and hot spring resources in Szu-Chung-Chi Area." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/xadvj6.

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碩士
國立成功大學
資源工程學系
103
The purpose of this research is to estimate the geothermal potential and hot spring resources in Szu-Chung-Chi area. A three-dimensional conceptual model has been developed based on the site information including lithological characters, hydrogeological data, etc. Then the simulator, TOUGH2, had been carried out to construct a comprehensive hydrothermal model of the study area. This model was calibrated by recharge rate and material hydrogeological parameters, as well as by monitoring groundwater level. In order to avoid the effect of artificial pumping, a natural-state model was obtained and be applied to evaluate the geothermal potential and determine reservoir properties. Results show that major heat flow flowed along the high-permeability fault zone. The quantity of hot deep circle water is 0.315 million tons and the enthalpy is 1.03×10^14 joule each year. Average heat flux over the entire study area is 110.1 mW/m^2. In second step, due to long-term exploitation, the water level in this area has been significantly decreased. So the natural state model was further calibrated by groundwater level during 2012-2014 to obtain the present state in site simulation. The final step of modelling was to predict the future state and the effect of reducing exploitation. In Scenario 1, two different kinds of recharge rates assumed to estimate groundwater level and results showed that groundwater recharge difference between wet year and dry year can affect the water table. In Scenario 2, reduced exploitation made water table rising and the result is benefit to hot spring management in research area.

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47

Widiatmoko, Fajar Rizki, and Fajar Rizki Widiatmoko. "Geothermal potential site selection using geo-scientific data integration approaches in Wae Sano area, Indonesia." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/534gh4.

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碩士
國立東華大學
自然資源與環境學系
106
Wae Sano volcano is located in Manggarai Barat Regency (MBR), Flores Island, Nusa Tenggara Timur Province, Indonesia. 70% houses of MBR are living without electricity. The Indonesian government is prioritizing the geothermal power plant instead of diesel power plant on this island. The World Bank has provided a grant of US$4.5 million for the exploration of geothermal potential site in Wae Sano in 2016. Volumetric reserves of this geothermal resource have been calculated using geophysical methods, the Wae Sano area stores an energy reserve of 64 Mw about 8 times more than those existing diesel power plants. The selection of a drilling target for this area is underway. A multi-criteria decision making approach is proposed to select a target site. The criteria include the data for creating geothermal resources suitability map such as the DEM (slope), rock type, geochemistry, and fault fracture density, the depth of the heat source, etc. Furthermore, the drilling depth to the heat reservoir is associated with the drilling cost and this should be weighted heavily. Data for creating the environmental, social, and law suitability map such as land use/land cover, accessibility factor, river, protected forest, social and environmental issues are also considered. To determine a well pad requires decisions that match the various factors of consideration. The site selection strategy using Boolean logic of "AND" and "OR" on overlaying those spatial data. The result shows the eastern slope of Wae Sano area is fulfilled the requirement in the geothermal resources suitability map but it is a large area of 0.040 km2. Further considering the area fulfills the requirement in the Environmental, social, and law suitability map, one can narrow down the suitable area and propose three possible sites for target drilling.

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48

Ruei-BangChen and 陳睿邦. "Numerical Modeling of Geothermal Energy Production Using a Closed-loop Heat Exchange Method In Zhiben Area." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/4cz3yx.

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49

Wang, Min-Hong, and 王閔弘. "Raman Spectrum and Cleavage Microstructure Analysis of Slate Carbonaceous Material in HongChaiLin Geothermal Well and Surrounding Area in Lanyang Plain, Taiwan." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/e2c2hq.

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碩士
國立臺北科技大學
資源工程研究所
106
In order to increase the use of green energy, geothermal development has been underway recently. The geological condition is suitable for geothermal exploration in the Lanyang Plain, and two deep wells in HongChaiLin were drilled. Researchers are eager to study underground strata to construct geological conceptual model for geothermal exploration. This study analyzes, the rock samples from outcrops surrounded the Lanyang Plain and the debris of some geothermal wells by mean of Raman microspectroscopy analysis in carbonaceous material for the temperature calculation related to the metamorphic grade. The data and assumed temperature range in this study area is fitted to the method proposed by Lahfid et al., 2010. When the grade of metamorphism increases, the grade of crystallization of carbon also increases. According to the Raman spectra of carbonaceous material parameters, calculated results in RA1=[(D1+D4)/(D1+D2+D3+D4+G)A] and RA2=[(D1+D4)/(D2+D3+G)A] shown closed relationship and can be used to indicate metamorphism temperature. Through the rock thin section petrography analysis, the feature of crystalline minerals and rock cleavage development levels, can also reveal the relative metamorphic grade. Based on the field information in temperature range and cleavage characteristics, the well cuttings of the HongChaiLin and other geothermal wells are analyzed and tried to differentiate Kankou Fm. from Hsuehshan Range and Lushan Fm. from Backbone Range. From the limited samplings, the result from the field samples indicate that metamorphic temperature and cleavage development are not closely related to the metamorphic grade due to the variations in particle size of the crystallization of minerals and the amount of flaky mineral, and local geological structures. Adjacent to the fault structure, the cleavage features is more obvious, and the metamorphic temperature implied is higher. From the well samples, the metamorphic temperature is correlated with depth, and the temperature rises with the increase of depth. There is no significant difference in the development of cleavage in the shallow strata. As a whole, from the perspective of metamorphism temperature, the Kankou Fm. of the Hsuehshan Range is higher than the Lushan Fm. of the Backbone Range in the study area. Ther Lushan Slate Belt in the northern part of the Backbone Range is widely distributed, and the grade of metamorphism increases from west to east, so part of the metamorphism temperature may be higher. The evidence from the analysis of Raman spectra of carbonaceous material and cleavage microstructure is not conclusive and hard to determine the exact formation from the shallow part of the HongChaiLin in cuttings.

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50

Boschmann, Darrick E. "Structural and volcanic evolution of the Glass Buttes area, High Lava Plains, Oregon." Thesis, 2012. http://hdl.handle.net/1957/36266.

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The Glass Buttes volcanic complex is a cluster of bimodal (basalt-rhyolite), Miocene to Pleistocene age lava flows and domes located in Oregon's High Lava Plains province, a broad region of Cenozoic bimodal volcanism in south-central Oregon. The High Lava Plains is deformed by northwest-striking faults of the Brothers Fault Zone, a diffuse, ~N40°W trending zone of en echelon faults cutting ~250 km obliquely across the High Lava Plains. Individual fault segments within the Brothers Fault Zone are typically <20 km long, strike ~N40°W, have apparent normal separation with 10-100 m throw. A smaller population of ~5-10 km long faults striking ~N30°E exhibits mutually crosscutting relationships with the dominant northwest striking faults. Basaltic volcanic rocks in the Glass Buttes area erupted during the late Miocene and Pleistocene. The oldest and youngest lavas are 6.49±0.03 Ma and 1.39±0.18 Ma, respectively, based on ⁴⁰Ar/³⁹Ar ages of five basaltic units. Numerous small mafic vents both within and around the margins of the main silicic dome complex are commonly localized along northwest-striking faults of the Brothers Fault Zone. These vents erupted a diverse suite of basalt to basaltic andesite lava flows that are here differentiated into 15 stratigraphic units based on hand sample texture and mineralogy as well as major and trace element geochemistry. The structural fabric of the Glass Buttes area is dominated by small displacement, discontinuous, en echelon, northwest-striking fault scarps that result from normal to slightly oblique displacements and are commonly linked by relay ramps. Northwest alignment of basaltic and rhyolitic vents, paleotopography, and cross-cutting relationships suggest these faults have been active since at least 6.49±0.03 Ma, the age of the rhyolite lavas in the eastern Glass Buttes are. Faults displace Quaternary sedimentary deposits indicating these structures continue to be active into the Quaternary. Long-term extension rates across northwest-striking faults calculated from 2-5 km long cross section restorations range from 0.004 – 0.02 mm/yr with an average of 0.12 mm/yr. A subordinate population of discontinuous northeast-striking faults form scarps and exhibit mutually cross-cutting relationships with the dominant northwest-striking population. Cross-cutting relationships indicate faulting on northeast-striking faults ceased sometime between 4.70±0.27 Ma and 1.39±0.18 Ma. Gravity data at Glass Buttes reveals prominent northwest- and northeast-trending gravity gradients that closely parallel the strikes of surface faults. These are interpreted as large, deep-seated, normal faults that express themselves in the young basalts at the surface as the discontinuous, en echelon fault segments seen throughout the study area and BFZ in general. Elevated geothermal gradients are localized along these deep-seated structures at two locations: (1) where northwest- and northeast-striking faults intersect,(2) along a very prominent northwest-striking active normal fault bounding the southwest flank of Glass Butte. High average heat flow and elevated average geothermal gradients across the High Lava Plains, and the presence of hydrothermal alteration motivated geothermal resource exploration at Glass Buttes. Temperature gradient drilling by Phillips Petroleum and others between 1977-1981 to depths of up to 600 m defined a local geothermal anomaly underlying the Glass Buttes volcanic complex with a maximum gradient of 224 °C/km. Stratigraphic constraints indicate that near-surface hydrothermal alteration associated with mercury ores ceased before 4.70±0.27 Ma, and is likely associated with the 6.49±0.03 Ma rhyolite eruptions in the eastern part of Glass Buttes. The modern thermal anomaly is not directly related to the pre-4.70±0.27 Ma hydrothermal system; rather it is likely a result of deep fluid circulation along major extensional faults in the area.
Graduation date: 2013
Includes accompanying DVD with digital data supplement (8 GB).

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