Hot spring geochemistry from the Peruvian Andes provide insight on how faults, or fractures in the Earth's crust, are capable of influencing fluid circulation. Faults can either promote or inhibit fluid flow and the goal of this study is test the role of a major fault, such as the Cordillera Blanca detachment, as a channel for transporting deep fluids to the surface. Hot springs are abundant in the Cordillera Blanca and Huayhuash ranges in Peru, and several springs issue along the Cordillera Blanca detachment, making this region an ideal setting for our study. To test the role of the Cordillera Blanca detachment, hot springs were sampled along the trace of the fault (Group 1), the western edge of the Cordillera Blanca (Group 2), the eastern side of the Cordillera Blanca (Group 3), and in the Cordillera Huayhuash (Group 4). Water and dissolved gas samples were collected from a total of 25 springs and then analyzed for an array of geochemical parameters. Distinct fluid chemistries from Groups 1 and 2 suggest that the Cordillera Blanca detachment and adjacent minor faults to the west intersect at depth and provide a preferential flow path for deep fluid circulation. Understanding the influence of faults on fluid flow is essential for many disciplines (e.g. oil exploration, hydrology), and this work demonstrates that fluid geochemistry is an excellent tool for assessing the role of faults on fluid distribution.

Mickey Springs in the Alvord Desert, southeast Oregon, is analogous to other Basin and Range hydrothermal systems where the requisite conditions of heat source and permeable pathways are met through crustal thinning due to normal faulting. This study examines the morphology and lifespan of near-surface spring features through use of ground penetrating radar, thermoluminescence (TL) dating, and elevation modeling. Duration of hydrothermal activity at Mickey Springs has not previously been determined, and age determinations of sinter at the site are conflicting. The reason for and timing of this change in silica saturation in the hydrothermal fluid has not been resolved. Three morphologies of silica sinter deposition have been identified at Mickey Springs. These are (1) well-sorted, fine-grained sandstone with ripple marks, cross beds and preserved root casts, to poorly-sorted conglomerate of primarily basalt clasts, both cemented by coeval silica deposition, (2) large depressions (12-32 m diameter) rimmed with sinter, characterized by fine silt and clay blanketing a sinter apron and infilling the central depression, and (3) quaquaversal sinter mounds identified by outcropping pool-edge sinter typically surrounding a shallow depression of loose sediment. Silica-cemented sandstone and conglomerate were the first features formed by coeval hydrothermal processes at the site, and were emplaced prior to 30 kya as suggested by structural and stratigraphic relationships. Structure between two interacting fault tips may have constrained the extent of silica cementation. By 30 kya, a left-stepping fault oriented roughly north/south further constrained the near-surface permeable zone. TL dates from sediment stratigraphically below and above sinter aprons around mounds and depressions (former spring vents) indicate sinter deposition between 30 and 20 kya. Location of these features was dictated by development of the left-stepping fault. As pluvial Lake Alvord filled at the end of the Pleistocene, lake sediment filled most vents, which were largely inactive, with fine-grained silt and clay. Today, hydrothermal activity persists in two modes: (1) The current high-temperature springs, steam vents and mudpots concentrated in a 50 x 50 m area south of the sinter mounds and depressions, and (2) scattered springs and steam vents that exploit previous permeable pathways that once provided the hydrothermal fluid which precipitated the sinter aprons. Currently there is no active silica sinter deposition at Mickey Springs. Structures and stratigraphic relationships identified through this study favor a transport-limited and structurally controlled model of fluid transport. Sinter deposition is determined to have occurred before the most recent highstand of pluvial Lake Alvord. A climate driven model, where groundwater recharge from pluvial Lake Alvord circulates to a deep heat source and enhances spring discharge, is not supported by these findings, as no evidence was found for sinter precipitation after the drying of the lake. Future studies of other hydrothermal systems in the Basin and Range may reveal that permeable pathways along local structures are the primary drivers in this region.

Architecture and music share intrinsic meanings generated by a constant stream of metaphors which are forms of poetic transformations. This thesis sought to challenge the present way an architect-musician makes drawings through the exploration of multimedia possibilities at hand. The drawings are composed using Macromedia Flash MX. OPEN HOMEPAGE.EXE To download flash player, click here: <a href="http://www.macromedia.com/shockwave/download/download.cgi?P1_Prod_Version=ShockwaveFlash"> Download flash Player</a> / Master of Architecture

M.Sc. (Environmental Management) / Geothermal springs exist on all continents of the Earth and are used for a myriad of different applications and uses. The last few years have witnessed a resurgence of interest in these springs due to a proliferation of utilisation of geothermal resources. Despite numerous benefits associated with their use, studies have shown that the water of geothermal springs could contain toxic elements, pathogenic organisms, toxic gases and even elements that are radio-active in nature that may have health impacts on users. The presence of some of these chemicals in the water and air can be traced back to the geological formations through which the thermal waters flow. More than 90 geothermal springs have been identified in South Africa. However, relatively little is known about how South African geothermal springs have been used in the past and how their geochemical composition and land-use around them has changed over time. There is also a scarcity of scientific literature dealing with environmental risk assessment associated with the different uses of geothermal spring water in South Africa. Given this research contextualization, the present study examined the overall water quality and assessed the potential health risks of the geothermal spring and associated waters (hydro spa and overflow pond) of the holiday resort of “Eiland” in the Limpopo Province. The research undertaken for this research project formed part of a bigger Water Research Commission (WRC) research project on geothermal springs in South Africa. Water samples were taken and observations were made of the resort waters during a field trip undertaken during August 2012. Chemical analyses of the samples were performed by the Agricultural Research Council (ARC): Institute for Soil, Climate and Water of South Africa (ISCW). Parameters under investigation included temperature, pH, electrical conductivity, total dissolved solids and various chemical constituents. A comparison of the laboratory results to previous years data and to four domestic water use standards/guidelines was made. These included the EU (1998), SABS (2006), SABS (2011) and the WHO (2011) domestic use water quality standards/guidelines. A risk assessment, based on Aucamp’s (2009) method, was performed for potentially harmful parameters. Overall, the waters of the resort were deemed to be of low risk and therefore not of a health and environmental risk to the users. Although the waters do not satisfy the domestic use water standards, they are suitable for the current recreational purposes of the resort. It is recommended however, that the soil sensitivity be determined for irrigational purposes and toxicology tests be conducted for the fish species inhabiting the overflow pond and small dam in order to determine the possible extent of bioaccumulation. It is recommended that geothermal waters are not used for bottling or for consumption for domestic or therapeutic purposes. In the event of expansion to include such uses a stringent new risk assessment is recommended.

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.

No / A profile across 8 layers from a fossil travertine terrace from a low temperature geothermal spring located in Svalbard, Norway has been studied using both Raman spectroscopy and SEM (Scanning Electron Microscopy) techniques to identify minerals and organic life signals. Calcite, anatase, quartz, haematite, magnetite and graphite as well as scytonemin, three different carotenoids, chlorophyll and a chlorophyll-like compound were identified as geo- and biosignatures respectively, using 785 and/or 514 nm Raman laser excitation wavelengths. No morphological biosignatures representing remnant microbial signals were detected by high-resolution imaging, although spectral analyses indicated the presence of organics. In contrast, in all layers, Raman spectra identified a series of different organic pigments indicating little to no degradation or change of the organic signatures and thus indicating the preservation of fossil biomarker compounds throughout the life time of the springs despite the lack of remnant morphological indicators. With a view towards planetary exploration we discuss the implications of the differences in Raman band intensities observed when spectra were collected with the different laser excitations. We show that these differences, as well as the different detection capability of the 785 and 514 nm laser, could lead to ambiguous compound identification. We show that the identification of bio and geosignatures, as well as fossil organic pigments, using Raman spectroscopy is possible. These results are relevant since both lasers have been considered for miniaturized Raman spectrometers for planetary exploration.

This research aims to investigate the diverse uses of thermal springs and to develop strategies to identify those most appropriate for Sagole with due regard given to the economic, social and environmental aspects. The aim specifically determines the optimum use of the Sagole thermal spring. The following potential uses for Sagole were identified, discussed and analysed in terms of the environmental, social and economic aspects: tourism, aquaculture and geothermal education. The potential cost and benefit of each were also analysed. According to the research finding, the establishment of a Geothermal Education Centre appears to be the most sustainable project with the highest Feasibility Index. It is followed by Health Tourism and then Aquaculture. / Environmental Sciences / D. Phil. (Environmental Management)

This research aims to investigate the diverse uses of thermal springs and to develop strategies to identify those most appropriate for Sagole with due regard given to the economic, social and environmental aspects. The aim specifically determines the optimum use of the Sagole thermal spring. The following potential uses for Sagole were identified, discussed and analysed in terms of the environmental, social and economic aspects: tourism, aquaculture and geothermal education. The potential cost and benefit of each were also analysed. According to the research finding, the establishment of a Geothermal Education Centre appears to be the most sustainable project with the highest Feasibility Index. It is followed by Health Tourism and then Aquaculture. / Environmental Sciences / D. Phil. (Environmental Management)

Planktothricoides raciborskii and Roseofilum reptotaenium are physiologically similar, yet ecologically distinct organisms found in a hot spring outflow and coral black band disease (BBD), respectively. The aim of this study was to elucidate the relationship between R. reptotaenium and sulfide in BBD, to compare microcystin (MC) production in response to environmental factors, and to determine chemotactic responses to MC and sulfide by the two organisms. Results showed that the pathogenicity of R. reptotaenium in BBD is dependent on sulfate-reducing bacteria as secondary pathogens. Roseofilum reptotaenium produced significantly more MC than P. raciborskii, as measured using ELISA. Roseofilum reptotaenium was negatively chemotactic to sulfide, determined using horizontal and vertical gradients in agar, while P. raciborskii was not affected. Neither cyanobacterium was chemotactic to MC in the agar assays. The ecophysiology of P. raciborskii and R. reptotaenium in relation to MC production and response to sulfide reflected their pathogenic versus non-pathogenic status.

No description available.