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John, Kangeze Biteme. "Ore forming potential of the Atchiza Suite and Sustainable management of mineral deposits in Mozambique : "Petrology, geochemistry and sustainable management of mineral deposits"." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for geologi og bergteknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-20380.
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Part 1- Abstract This research study presents detailed petrographic- and geochemical- analysis of 63 rock samples from the Atchiza Suite. The Suite is a layered mafic-ultramafic pluton located in the Tete Suite, of NW Mozambique. At present, the Atchiza comprises a group of three main types of rock that are classified based on their mineralogy, textures, geochemical composition. These are ultramafic cumulates (dunite and pyroxenites), mafic cumulates (medium-grained cumulate gabbro) and coarse-grained gabbro (non-cumulate gabbro). Compared to the rest of other rocks, coarse-grained gabbro shows high enrichment of Ti (0.64-3.46 wt% TiO2), Zr (5.9-296.1 5ppm), Sr (253.7-1268.4ppm) and V (224-952.3ppm), but relatively low depleted in compatible elements (Ni = 48.7-235.7ppm , Cr = below detection limit to 410.5ppm). Cumulate ultramafics are highly enriched in compatible elements (Ni up to 4636.2ppm, Cr up to 4721ppm). A high Mg# in ultramafic cumulates (0.59-0.86) suggests an Mg-rich primitive parental magma, whereas a low Mg# in coarse-grained gabbro (0.23-0.37) suggests a relatively high-differentiated magma. Cumulate gabbro shows Mg# ranging from 0.40-0.72, suggesting a moderately evolved magma source (derivative magma subsequent to fractionation of ultramafic cumulates). The Ni/Zr, Cr/Zr, Sr/Zr and Ti/Zr ratios are generally the lowest in coarse-grained gabbro when compared to cumulate rocks. The same applied; this suggests that coarse-grained gabbros were probably formed from a relatively high-differentiated magmatic liquid. In addition, the presence of an uninterrupted cryptic differentiation trend with these ratios implies that the Atchiza igneous lithologies were derived from one and the same parental melt. Apparently, Atchiza shows great variability of Fe2O3, SiO2 and SO3 during magmatic differentiation. There is significant decrease in Fe2O3, an increased SiO2 and SO3 contents in residual magma during progressive magma fractionation. It is true that all these geochemical changes will lower down the solubility of S in the system, thus providing a favourable condition for silicate-sulfide immiscibility. Theoretically, therefore, the Atchiza may have a potential to host Ni-Cu-(PGE) sulfide deposits. Part 2- Abstract Unlike water and forests, minerals are finite resources; they cannot be replaced back to their natural forms once they are depleted. For that reason, sustainable management of mineral resources is very important so that stakeholders in the extractive sector are guaranteed the same opportunities in sharing benefits. As part of this study, and with respect to Atchiza Suite, this section is discussing sustainable management of mineral deposits in Mozambique. Investment in Mozambican extractive industry should primarily be done with the main objective of poverty reduction for Mozambican citizens. Thus, the Mozambican Government needs to realize that proper management of mineral deposits will provide sufficient income for the country, enough to fund other development projects. Rather than being mismanaged, this massive collection of mineral revenues needs to be appropriately re-invested back to diversify other economic sectors. If this mineral revenue is managed wisely, the national annual budgets will be sufficiently supported. Most importantly, the country’s reliance on international loans and aids will be reduced significantly. Decision-making for development of the country’s mineral projects should not be central-governed; rather it should be transparent to the public and open for opinions and suggestions. As the main stakeholder in Mozambican extractive sector, local communities and civil societal groups should also be given opportunities to participate in decision-making, important for the development of mining projects. Mineral agreements for which the Mozambican State has been signing with multinational companies for development of the country’s mineral projects need to be published and be available publicly. In addition, negotiation of mining agreements must be transparent and involve all stakeholders. Investment and development of the country’s mineral projects must be performed through partnerships and Joint ventures between multinational mining companies, national-based companies and the Mozambican State. Development of mineral deposits must incorporate environmental sustainability. Despite its high mineral potential (e.g. Ni-Cu-PGE-Ti-V), Atchiza also is surrounded by a wide range of other natural resources. The Cahora Bassa Dam, which is located just adjacent to Atchiza Project, is the main source of clean energy not only for Mozambique domestic market, but also for the majority of Sub-Saharan countries. All of these natural resources require good practice of Environmental sustainability in mining activities.
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Sulaeman, Hanif Ibadurrahman. "Discovery of Paleotsunami Deposits along Eastern Sunda Arc: Potential for Megathrust Earthquakes in Bali." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7178.
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Several laterally extensive candidate tsunami deposits are preserved along coastlines facing the eastern Java Trench, indicating it has experienced mega-thrust earthquakes in the past. We investigated 37 coastal sites in Bali, Lombok, Sumba and Timor islands, many of which preserve course sand and pebble layers that overlie sharp basal contacts with scour marks into the mud, fine upward in grain size, and have bimodal grain size distributions. Other unique features are the common occurrence of marine fossils and concentrations of heavy minerals. The occurrence of these high-energy deposits interlayered with clay-rich units indicates the coarse clastics are anomalous because they were deposited in what is normally a very low-energy depositional environment. The lateral extent and paucity of thin, coarse clastic layers with marine organisms are inconsistent with local stream flood event, and the proximity to the equator of the sites diminishes the possibility of marine flood events from cyclones. The sparse, but consistent, the occurrence of at least two candidate tsunami deposits at depths of 1 and 2 meters over 950 km along the strike of the Java Trench may reveal that mega-thrust earthquakes have occurred there and generated giant tsunamis in the recent past. Five widely scattered imbricated boulder deposits are also found on Bali, Lombok, and Sumba. The boulders consist of slabs of hardpan up to 2.5 m in length and 80 cm thick that was torn from a near-shore seabed and stacked on top of one another. Some of the boulders were carried over the erosional coastal bank and deposited up to 100 meters inland. Comparisons with imbricated boulder ridges formed during the 1994 tsunami in east Java indicate that these deposits are from one or multiple tsunamis sourced by the Java Trench. Experiments in effective ways to communicate and implement tsunami disaster mitigation strategies have led us to train local communities about the 20-20-20 rule. If coastal communities experience more than 20 seconds of shaking from an earthquake, even if it is not intense, they should evacuate the coast. The time delay between the earthquake and arrival of tsunami waves is around 20 minutes, which is the time window for evacuation. Some tsunami waves may be as high as 20 meters, which is the target elevation for evacuation. Adopting the 20-20-20 rule could save thousands of lives throughout the region, especially in Bali where nearly 1 million people inhabit likely tsunami inundation zones.
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Michnowicz, Sabina Anna Katarzyna. "Exploratory study of the potential airborne health hazard of dusts generated by quarrying volcanic deposits." Thesis, Durham University, 2014. http://etheses.dur.ac.uk/10919/.
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Occupational exposure to dust generated by quarrying siliceous rocks (i.e. sandstone, coal) is a well documented respiratory hazard. Hazard of volcanic ash inhalation is also routinely studied (although less well understood), but the specific respiratory hazard of quarried volcanic deposits is entirely under-researched and is the focus of this study. The two main factors potentially implicated in respiratory toxicity of volcanic quarry dust are: i) crystalline silica content implicated in silicosis and lung cancer; and ii) iron-catalysed hydroxyl radical generation, implicated in inflammation and carcinogenesis. Twelve sites (in New Zealand, Montserrat and Greece), quarrying a range of volcanic deposits, were investigated and compared with volcanic ash samples (to test suitability as an analogue) and dust from non-volcanic quarries (greywacke and sandstone) in an investigation of the physicochemical characteristics which may influence particle surface reactivity. Samples of deposited dust (<1mm size fraction) were collected and 11 of these separated to ≤10μm for further analyses. Compositional analyses (XRF) showed the samples spanned the range of magmatic compositions from mafic to felsic (44-76 wt.% SiO2). The finest material was generated by drilling lava flows (8.3-27.5 cu.vol% <10 μm diameter particles in <1mm fraction), however, several other sample types (i.e. dust on processor) contained high levels of respirable material, akin to volcanic ash from equivalent eruption settings. SEM analyses confirmed particles to be blocky and angular, having aspect ratios between 0.59-0.70 (<10μm fraction). Crystalline silica content was highest (up to 28 wt. %) in dusts from intermediate and felsic quarries where lava domes (or collapse deposits) are mined. Similar levels were observed for dome-collapse ash and greywacke quarry dusts; however, the sandstone quarry dust was 99 wt.% crystalline silica. Hydroxyl radical generation was lower for quarried volcanic samples than for either volcanic ash or sandstone (significant to p≤0.01 for mafic ash/quarry dust). Haemolysis (erythrocyte membrane rupture, an indicator of quartz reactivity) was exhibited by six samples from three quarries, and comparable to the DQ12 quartz positive standard, when adjusted for surface area. These findings may be influenced by the presence of clays, however, as haemolytic samples included those with little crystalline silica. Airborne dust levels (both role-specific and ambient) were measured in the quarries and were mostly within international exposure limits, however, interpretations were limited by the duration of measurements so further work is required. Some workers’ shifts were longer than 8 hours, and workers on Montserrat may also be simultaneously exposed to volcanic ashfall, which should be considered with respect to adherence to regulations in those quarries. Mitigation measures were variable and workers would benefit from better awareness regarding use of non-mandatory respiratory protection. Volcanic quarries pose a hazard distinct from volcanic ash and from non-volcanic quarries. Overall, hazard may be lower than for quarrying other rock types, but further research is needed to better constrain the potential hazards. Until then, a precautionary approach might be taken in quarries where respirable dust levels are high and deposits may contain crystalline silica or iron.
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Malehmir, Alireza. "3D Geophysical and Geological Modeling in the Skellefte District: Implications for Targeting Ore Deposits." Doctoral thesis, Uppsala University, Department of Earth Sciences, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8188.
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With the advancements in acquisition and processing of seismic reflection data recorded over crystalline rocks, building three-dimensional geologic models becomes increasingly favorable. Because of little available petrophysical data, interpretations of seismic reflection data in hardrock terrains are often speculative. Potential field data modeling are sometimes performed in order to reduce the ambiguity of seismic reflection interpretations. The Kristineberg mining area in the western part of the Paleoproterozoic Skellefte Ore District was chosen to construct a pilot three-dimensional geologic model in an attempt to understand the crustal architecture in the region and how the major mineral systems operated in this architecture. To contribute to this aim, two parallel seismic reflection profiles were acquired in 2003 and processed to 20 sec with special attention to the top 4 sec of data. Several reflections were imaged and interpreted by the aid of reflector modeling, borehole data, 2.5D and 3D potential field modeling, and geological observations. Interpretations are informative at the crustal scale and help to construct a three-dimensional geologic model of the Kristineberg mining area. The three-dimensional geologic model covers an area of 30×30 km2 down to a depth of 12 km. The integrations help to interpret a structural basement to the Skellefte volcanic rocks, possibly with Bothnian Basin metasedimentary affinity. The contact is a shear-zone that separates the two units, generating large fold structures, which can be observed in the region. The interpretations help to divide the Revsund granitic rocks into two major groups based on their present shape and thickness. A large gravity low in the south is best represented by the intrusion of thick dome of Revsund granite. In the north, the low-gravity corresponds to the intrusion of sheet-like Revsund granites. In general, the structure associated with the Skellefte volcanics and the overlying metasedimentary rocks are two thrusts exposing the Skellefte volcanic rocks in the cores of hanging wall anticlinal structures. Lack of coherent reflectivity in the seismic reflection data may be due to complex faulting and folding systems observed in the Skellefte volcanics. Ultramafic sills within the metasedimentary rocks are interpreted to extend down to depths of about 5-6 km. The interpretations are helpful for targeting new VHMS deposits and areas with gold potential. For VHMS deposits, these are situated in the southern limb of a local synformal structure south of the Kristineberg mine, on the contact between the Revsund granite and the Skellefte volcanic rocks. A combination of metasedimentary and mafic-ultramafic rocks are highly gold prospective in the west, similar to observations elsewhere in the region. There are still questions that remain unanswered and need more work. New data in the study area will help to answer questions related to e.g., an enigmatic diffraction seismic signal in Profile 5 and the structural relationship between the Skellefte volcanic rocks and the Malå volcanics. Although the derived 3D geologic model is preliminary and constructed at the crustal scale, it provides useful information to better understand the tectonic evolution of the Kristineberg mining area.
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Makhubele, Marvel M. H. "The role of salt tectonics in the hydrocarbon potential of the post-salt deposits (Albian to Recent), offshore Gabon." Thesis, University of Western Cape, 2014. http://hdl.handle.net/11394/3497.
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Magister Scientiae - MScFollowing successful discovery and production of hydrocarbons, Gabon is one of the key hydrocarbon target countries in Africa. Located in the Lower Congo Basin, the study area is based in Etame Marin Permit (EMP), which is licensed to VAALCO Energy Inc., and has been producing hydrocarbons since 2002. The currently explored and producing reservoirs are in the pre-salt sandstones of the Aptian Gamba Formation, charged with hydrocarbons sourced from the syn-rift lacustrine shale of the pre-Aptian Melania Formation. With the aim of finding potential petroleum plays in the post-salt successions and by using 3D prestack depth migration (PSDM) seismic sections and wireline logs, a detailed study of the post-Aptian stratigraphy and salt tectonics of the EMP was undertaken. Eight distinct reflectors were identified based on gamma ray signatures, stratal terminations and isopach trends. Sediment distribution patterns and the relative sea level history of the succession were determined by applying principles of sequence stratigraphy and salt tectonics. Furthermore, two potential plays have been outlined in the post-salt carbonates of the Albian Madiela Formation as well as in sandstones of the Turonian Azile Formation. These reservoirs might have been charged with hydrocarbons from the pre-salt shale of the Melania Formation and/or potentially also enriched from the Albian and Cenomanian shales. For these post-salt hydrocarbon reservoirs to be charged by the pre-salt source rocks, windows within the extensive evaporitic sealing of the Aptian Ezanga Formation were required. 3D PSDM seismic sections attest that diapirism of the Aptian salt unit generated ample hydrocarbon migration pathways from the pre-salt source rocks to post-salt reservoirs. Five well-developed potential salt windows have been identified, two of which have good probability to have facilitated the upward migration of hydrocarbons, because these salt windows are located up dip of oil producing wells. However, even if hydrocarbons are found in the post-salt reservoirs, similarly to the Yombo Field (located offshore Congo, south of the EMP), these shallow reservoirs in the EMP are likely to produce heavy oils due to biodegradation.
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Weatherington-Rice, Julie Bishop Paynter. "Fracture occurrence and ground water pollution potential in Ohio's glacial and lacustrine deposits: a soils, geologic, and educational perspective." The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1072118096.
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Reardon, Timothy W. "Modern Marine Sediments of Bahia Concepcion : Patterns, Processes, and Potential Analogues to Neogene Rift Basin deposits of Baja California." Oberlin College Honors Theses / OhioLINK, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin1411645561.
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Akçay, Migraç. "Genesis of the stibnite-cinnabar-scheelite deposits of the Gumusler area, Nigde, central Turkey and implications on their gold potential." Thesis, University of Leicester, 1994. http://hdl.handle.net/2381/34995.
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The project aims to describe the geology and hydrothermal fluid evolution of mineral deposits of the Gumusler area in the Nigde massif. Two types of deposits can be differentiated in this area: Sb Hg W Ba Au veins and associated replacement type Ba- Sb mineralization at the Rasih-Ihsan deposit, and a breccia hosted Hg Sb Au prospect at the Mehmetler Yurdu Sivrisi Tepe (MYST). The vein deposits are localized along E-W trending and N-dipping faults in marbles, and along marble-gneiss contacts. There is a spatial relationship between the mineral deposits and the felsic dykes of Cenomanian age which are cut by tlie Sb-Hg- W Ba vein. Similar dykes, together with intensive fracturing of marbles along the gneiss- marble contacts, also contributed to the formation of approximately E-W trending breccias containing the Hg Sb Au prospect at the MYST area. The Gumusler deposits have a diverse mineralogy including scheelite, barite, stibnite, cinnabar, sulphosalts and gold. Gold is associated with the cinnabar deposition stage, and is locally enriched in near surface zones with concentrations as high as 37 ppm at the MYST prospect. Silicification is the dominant wall rock alteration at the mineralized locations but sericitization, kaolinization, dolomitization and tourmalinization also occur at the periphery of the mineralization. Mineral deposition took place from aqueous fluids over a wide temperature range ( 350 °C to 150 °C). The pre-sulphide alteration (tourmalinization) occurred from fairly saline (8 2.5 eq. wt % NaCl) and moderately high temperature (216-254 °C) fluids. The main barite deposition also took place from fairly saline (8 2.5 eq. wt % NaCl) fluids at temperatures of 149-213 °C which are diluted towards the stibnite stage with a salinity of 4 eq. wt % NaCl and a temperature range of 137-168 °C. This probably indicates increasing involvement of non-magmatic waters. delta34S values of pyrite and stibnite range from -4.3 to +2.2 ‰ whereas those of barite are ~18 %, which suggests a magmatic origin for the sulphur of both sulphide and sulphate. Tourmaline mineral chemistry of hydrothermal alteration zones indicates a mixture of granitic and metapelitic sources, but comparison with tourmalines of other magmatic deposits favours a magmatic origin for boron.
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Minde, Peder. "Clast analysis of potential resurge deposits as part of the Vakkejokk Breccia in the Torneträsk area, northern Sweden - a proposed impact ejecta layer." Thesis, Stockholms universitet, Institutionen för geologiska vetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-143782.
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In the northern part of Swedish Caledonides, north of Lake Torneträsk is a 7 km long exposure of a breccia layer. The layer thins westwards and eastwards from the central part where it is up to 27 m thick. It is called the Vakkejokk Breccia after the type section. The breccia has been described in literature since about a century, but its origin is enigmatic. The breccia layer is since the summer of 2012 investigated by three geologists specialized in impact craters, Paleozoic sediments, and the Caledonian orogeny. They put forward evidence for the breccia being formed by a hypervelocity impact during the Lower Cambrian at approximately 520 Ma (Ormö et al. 2017). At that time the target area was a shallow epicontinental sea that surrounded the mainly peneplanized continent Baltica. An impact into the sea is known to generate tsunami waves as well as resurge deposits when the water brings ejected and rip-up material back into the crater. Ormö et al. (2017) suggest the top part of the Vakkejokk Breccia to include such resurge deposits. The depositional marine environment is also known to rapidly protect an impact crater from further erosion. It is possible that only the topographic rim of the Vakkejokk crater was eroded during the millions of years it may have taken before the crater was covered by younger sediments. About 100 m.y. after the formation, it was completely covered by overthrust nappes during the Caledonian orogeny, when Baltica and Laurentia collided. The crater itself is not exposed today, merely parts of what is thought to be the ejecta layer and resurge deposits. This Bachelor of Science project aimed to investigate the putative resurge deposits to learn more about the process of formation and the provenance in the target of the clasts in the deposits. This was carried out by three short drillcores through the resurge deposit part of the Vakkejokk Breccia layer. The place to drill the boreholes was chosen at an outcrop which is proximal to the putative hidden crater. The retrieved drillcores were cut longitudinally, then polished and photographed in high resolution. Each core was then analyzed in an image analysis software with respect to clast granulometry and lithology. To the results are presented as graphs showing clast size, size sorting, clast shape, of the relative amounts of different lithologies and the matrix content. The results are discussed with respect to well-documented analogue marine-target craters
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Dwairi, I. M. A. "A chemical study of the palagonitic tuffs of the Aritain area of Jordan, with special reference to nature, origin and industrial potential of the associated zeolite deposits." Thesis, University of Hull, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233955.
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Daneshfar, Bahram. "An evaluation of indicators of prospectivity and potential mapping of porphyry deposits in middle & southern British Columbia by a GIS study of regional geochemical and other geoscientific data." Thesis, University of Ottawa (Canada), 1998. http://hdl.handle.net/10393/4119.
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This thesis presents mineral potential maps for prospecting porphyry deposits at the regional scale. The study area covers certain geological units in southern and middle British Columbia (from 48°N to 56°N) that are known for hosting major porphyry deposits. Four main types of data were used in this thesis, namely geochemical, geophysical, tectonic and distribution of known porphyry deposits. Several "evidence" maps were generated based on these data sets. These maps can indicate areas with porphyry mineralizations inside the study area. The "evidence" maps were combined to create potential maps for porphyry deposits. Such potential maps show the gradation of favourability within different areas for prospecting porphyry deposits. The fuzzy logic method was utillised for representing the relative importance of maps and map combinations. The stream geochemical dataset showed a "boundary shift" for some elements between a number of the National Geochemical Reconnaissance (NGR) surveys map sheets. In such cases, the data for stream sediment and water samples were levelled prior to statistical or GIS analysis. For levelling the geochemical data, a method was presented to estimate the required width for the bands that must be selected at the contact of the map sheets with a "boundary shift". The geochemical data were disaggregated based on the geological environment and univariate and multivariate analyses were performed on these subsets of data. It was noticed that the median of Cu in stream sediments was often a good predictor of porphyry deposits. In many cases parameters measuring the spatial variability of Cu and Mo, such as variance or slope (maximum first spatial derivitive) of these elements in a moving cell, were good indicators of potentially mineralized zones. In addition, the results of multivariate techniques such as factor and discriminant analysis could often be used as good indicators of mineralized areas. Residual total field magnetics and vertical derivative (gradient) of magnetics were also good indicators of porphyry Cu-Au and Cu-Mo mineralizations at the regional scale. At this scale areas with high density of faults show also strong association with the location of known porphyry deposits. Areas close to known porphyry deposits and mining camps were subtracted from the final potential maps to introduce only those areas predicted by this model, with no known porphyry deposits. In application of GIS at the regional scale, diversity of geology along the study area must be considered. It was noticed that evidences introduced by the univariate and multivariate analysis of geochemical data can be very useful at the regional scale if the geochemical data is first separated based on the similarity of geological environment. Such a separation enhances any statistical analysis at the regional scale.
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Zehni, Addi. "Geologie, mineralogie et geochimie du gisement de pb(zn-cu) de beddiane (district de touissit-boubeker, maroc oriental)." Toulouse 3, 1988. http://www.theses.fr/1988TOU30145.
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Le gisement de beddiane appartient au district de touissit-bou beker, "chaine des horsts", maroc oriental. Il est encaisse dans la serie alleno-bajocienne, discordante sur le socle paleozoique, et se caracterise, par rapport aux gisements voisins, par sa richesse exceptionnelle en plomb, des concentrations exploitables de cuivre et peu de zinc. L'analyse sedimentologique de la formation carbonatee encaissante a permis de mettre en evidence des sequences transgressives et regressives, traduisant un environnement geologique instable: subsidences saccadees et emersions temporaires, suivies de phenomenes de dissolution-karstification pendant et apres le depot de la formation. L'examen petrographique a permis de distinguer plusieurs types de dolomies et de mettre en evidence deux phases principales de dolomitisation: un diagenetique precoce et une autre epigenetique, tardive. La lithogeochimie, effectuee a partir des carottes de sondages, a montre que toutes les assises carbonatees, sont fortement anormales en pb, zn et cu et plus particulierement les facies micritiques. Trois phases de mineralisations zn, pb et cu ont ete distinguees. La zonalite verticale et horizontale des mineralisations au sein du gisement et la geometrie des karsts mineralises suggerent que les solutions salines hydrothermales (100**(o)c) aient circule d'ouest en est dans cette couverture carbonatee. La presence dans le socle sous-jacent de filons a pb-cu pourrait temoigner d'une origine plus profonde des fluides mineralisateurs
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Semmens, Stephen Bradley. "An Engineering Geological Investigation of the Seismic Subsoil Classes in the Central Wellington Commercial Area." Thesis, University of Canterbury. Geological Sciences, 2010. http://hdl.handle.net/10092/4287.
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The city of Wellington has a high population concentration and lies within a geologically active landscape at the southern end of the North Island, New Zealand. Wellington has a high seismic risk due to its close proximity to several major fault systems, with the active Wellington Fault located in the north-western central city. Varying soil depth and properties in combination with the close proximity of active faults mean that in a large earthquake rupture event, ground shaking amplification is expected to occur in Thorndon, Te Aro and around the waterfront.
This thesis focuses on the area bounded by Thorndon Overbridge in the north, Wellington Hospital in the south, Kelburn in the west, and Oriental Bay in the east. It includes many of the major buildings and infrastructural elements located within the central Wellington commercial area. The main objectives were to create an electronic database which allows for convenient access to all available data within the study area, to create a 3D geological model based upon this data, and to define areas of different seismic subsoil class and depth to rock within the study area at a scale that is useful for preliminary geotechnical analysis (1:5,000.
Borelogs from 1025 holes with accompanying geological and geotechnical data obtained from GNS Science and Tonkin & Taylor were compiled into a database, together with the results from SPAC microtremor testing at 12 sites undertaken specifically for this study. This thesis discusses relevant background work and defines the local Wellington geology.
A 3D geological model of the central Wellington commercial area, along with ten ArcGIS maps including surficial, depth to bedrock, site period, Vs30, ground shaking amplification hazard and site class (NZS 1170.5:2004) maps were created. These outputs show that a significant ground shaking amplification risk is posed on the city, with the waterfront, Te Aro and Thorndon areas most at risk.
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Oliveira, Junior Osvaldo Novais de. "Electrical properties of Langmuir monolayers and deposited Langmuir-Blodgett films." Thesis, Bangor University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236716.
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Liang, Liqun. "Development of an energy method for evaluating the liquefaction potential of a soil deposit." Case Western Reserve University School of Graduate Studies / OhioLINK, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=case1058541489.
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Wiley, Devon S. "Oxide Nanofilms from Nanoparticle Suspensions Deposited on Functionalized Surfaces." Case Western Reserve University School of Graduate Studies / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=case1217022473.
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Razafimbelo, Eugène. "Le bassin de morondava (madagascar) : synthese geologique et structurale." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13184.
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La synthese des donnees geologiques et structurales du bassin de morondava conduit a modifier la nomenclature stratigraphique des formations sedimentaires du type "karroo". Dans le bassin, le controle tectonique de la sedimentation est realise par un jeu complexe mais permanent de failles en faisceaux denses. La fracturation continentale a permis la mise en place de roches effusives basaltes et gabbros, puis roches granito-syenitiques. L'epaisseur et la nature des formations sedimentaires du bassin de morondava sont propices a la naissance de gisements d'hydrocarbures
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Singh, Gargi. "Influence of Petroleum Deposit Geometry on Local Gradient of Electron Acceptors and Microbial Catabolic Potential." Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/31431.
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A field survey was conducted following the Deepwater Horizon blowout and it was noted that resulting coastal petroleum deposits possessed distinct geometries, ranging from small tar balls to expansive horizontal oil sheets. A laboratory study evaluated the effect of oil deposit geometry on localized gradients of electron acceptors and microbial community composition, factors that are critical to accurately estimating biodegradation rates. One-dimensional top-flow sand columns with 12-hour simulated tidal cycles compared two contrasting geometries (isolated tar â ballsâ versus horizontal â sheetsâ ) relative to an oil-free control. Significant differences in the effluent dissolved oxygen and sulfate concentrations were noted among the columns, indicating presence of anaerobic zones in the oiled columns, particularly in the sheet condition. Furthermore, quantification of genetic markers of electron acceptor and catabolic conditions via quantitative polymerase chain reaction of dsrA (sulfate-reduction), mcrA (methanogenesis), and cat23 (oxygenation of aromatics) genes in column cores suggested more extensive anaerobic conditions induced by the sheet relative to the ball geometry. Denaturing gradient gel electrophoresis similarly revealed that distinct gradients of bacterial communities established in response to the different geometries. Thus, petroleum deposit geometry impacts local redox and microbial characteristics and may be a key factor for advancing attenuation models and prioritizing cleanup.Master of Science
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Carlborg, Ylva. "Ash transformation during combustion of phosphorus-rich industrial sludge : Investigation of phosphorus recovery potential, and effects on emissions and deposit formation." Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-103834.
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Effective use of resources is essential in the development towards a sustainable industry. Waste products, such as sludge from industrial waste water treatment, often contain valuable reserves of plant nutrients but this resource is nonetheless commonly disposed of as contaminated waste. Approximately 1 500 ton phosphorus per year is added in biological waste water treatment at the Swedish pulp and paper industries and this non-renewable resource thereby ends up in their so called biosludge. The most common way to discard the sludge is by incineration. Besides the high levels of phosphorus, the biosludge usually contains high levels of moisture and ash forming elements, sulfur and chlorine, which makes it a rather problematic fuel. The aim with this study was to investigate different aspects on ash transformation chemistry during co-combustion of biosludge, from the pulp and paper mill SCA Packaging Obbola AB, with wood fuels and wheat straw. The phosphorus recovery potential, and the effects on deposit formation and emissions, were examined by SEM-EDS- and XRD-analysis of ash from co-combustion experiments. The experimental results were complemented with theoretical analysis based on thermochemical equilibrium calculations. The biosludge from SCA Obbola contained high levels of Ca which had a large impact on the ash transformation reactions. Most of the phosphorus from the fuels stayed in the solid ash during combustion, and in all ash assortments, except for the pure wood fuel, it was primarily found in the crystalline structure whitlockite, Ca9(K,Mg,Fe)(PO4)7. Hydroxyapatite, Ca5(PO4)3OH, was identified in ash from combustion of the pure wood fuel and wheat straw, and in the mixture of biosludge and wood fuels with the lowest proportion of sludge. Of the two phosphorus compounds, hydroxyapatite is more difficult to break down. It is therefore promising from a phosphorus recovery perspective that whitlockite was the main phosphorus compound in most of the ash assortments. Some of the sulfur in the sludge reacted with Ca and formed solid CaSO4, which stayed in solid ash during combustion, while chlorine generally left the bottom ash by volatilization. K- and Si-rich agricultural residues, such as wheat straw, are associated with a number of ash-related problems, including deposit formation due to low ash-melting points. During co-combustion of biosludge and wheat straw, the melting tendencies of the wheat straw ash elements were examined. According to the thermochemical equilibrium calculations, the composition of the mixed fuels would result in a significantly higher initial slag formation temperature compared to the pure wheat straw. This trend was also observed in the experimental results. It is likely that the relatively high levels of Ca, Al and P in the sludge all contributed to reduced slag formation in the wheat straw ash, by formation of ash compounds with higher melting temperatures. The high calcium levels may however have reduced some of the positive effects of increased P and Al contents by these elements preferably reacting with Ca instead of capturing alkali in crystalline structures.
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Holschbach, Martin Herbert. "Untersuchungen zum immunmodulatorischen Potential von Terpenoiden." Berlin Logos-Verl, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=3049354&prov=M&dok_var=1&dok_ext=htm.
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Rahn, Mirjam Christina Verfasser], P. A. [Akademischer Betreuer] Kukla, and Bernd G. [Akademischer Betreuer] [Lottermoser. "Deep-sea mining of seafloor massive sulfides and seafloor manganese nodules : deposit modelling and market potential / Mirjam Christina Rahn ; P. A. Kukla, Bernd Georg Lottermoser." Aachen : Universitätsbibliothek der RWTH Aachen, 2019. http://d-nb.info/1194067085/34.
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Meurer, Michael. "Empfängerorientierte Funkkommunikation Grundzüge, Potential und Ausgestaltung einer unkonventionellen Übertragungstechnik für die Mobilkommunikation." Kaiserlautern Techn. Univ, 2005. http://deposit.d-nb.de/cgi-bin/dokserv?idn=977111679.
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Henggeler-Müller, Jeannette. "The Potential for contagion in the Swiss interbank market." Berlin dissertation.de, 2006. http://deposit.d-nb.de/cgi-bin/dokserv?id=2903771&prov=M&dok_var=1&dok_ext=htm.
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Hoppmann, Luisa. "Wirtschaftlichkeit von Binnenhäfen Potentiale von Transportketten." Saarbrücken VDM, Müller, 2006. http://deposit.d-nb.de/cgi-bin/dokserv?id=2853059&prov=M&dok_var=1&dok_ext=htm.
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Müller, Timo. "Interpersonale Gewalt und Individualität in der spätmodernen Gegenwartgesellschaft Zusammenhänge und figurative Potentiale einer Gewaltreduzierung /." Kassel : Kassel Univ. Press, 2006. http://deposit.d-nb.de/cgi-bin/dokserv?idn=985548193.
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Heerdegen, Jenny. "Das Bild in der Werbung Gestaltung, Potentiale, Entwicklung." Saarbrücken VDM, Müller, 2004. http://deposit.d-nb.de/cgi-bin/dokserv?id=2889524&prov=M&dok_var=1&dok_ext=htm.
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Heerdegen, Jenny. "Das Bild in der Werbung : Gestaltung, Potentiale, Entwicklung /." Saarbrücken : VDM, Müller, 2006. http://deposit.d-nb.de/cgi-bin/dokserv?id=2889524&prov=M&dok_var=1&dok_ext=htm.
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Williams, Nicholas Cory. "Geologically-constrained UBC–GIF gravity and magnetic inversions with examples from the Agnew-Wiluna greenstone belt, Western Australia." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2744.
Full textAbstract:
Geologically-constrained inversion of geophysical data is a powerful method for predicting geology beneath cover. The process seeks 3D physical property models that are consistent with the geology and explain measured geophysical responses. The recovered models can guide mineral explorers to prospective host rocks, structures, alteration and mineralisation. This thesis provides a comprehensive analysis of how the University of British Columbia Geophysical Inversion Facility (UBC–GIF) gravity and magnetic inversions can be applied to subsurface mapping and exploration by demonstrating the necessary approach, data types, and typical results.
The non-uniqueness of inversion demands that geological information be included. Commonly available geological data, including structural and physical property measurements, mapping, drilling, and 3D interpretations, can be translated into appropriate inversion constraints using tools developed herein. Surface information provides the greatest improvement in the reliability of recovered models; drilling information enhances resolution at depth. The process used to prepare inversions is as important as the geological constraints themselves. Use of a systematic workflow, as developed in this study, minimises any introduced ambiguity. Key steps include defining the problem, preparing the data, setting inversion parameters and developing geological constraints.
Once reliable physical property models are recovered they must be interpreted in a geological context. Where alteration and mineralisation occupy significant volumes, the mineralogy associated with the physical properties can be identified; otherwise a lithological classification of the properties can be applied. This approach is used to develop predictive 3D lithological maps from geologically-constrained gravity and magnetic inversions at several scales in the Agnew-Wiluna greenstone belt in Australia’s Yilgarn Craton. These maps indicate a spatial correlation between thick mafic-ultramafic rock packages and gold deposit locations, suggesting a shared structural control. The maps also identify structural geometries and relationships consistent with the published regional tectonic framework.
Geophysical inversion provides a framework into which geological and geophysical data sets can be integrated to produce a holistic prediction of the subsurface. The best possible result is one that cannot be dismissed as inconsistent with some piece of geological knowledge. Such a model can only be recovered by including all available geological knowledge using a consistent workflow process.
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Bonnet, Wolfram. "Potentiale zur Entwicklung eines Nanotechnologieclusters am Beispiel der Region Münster." Saarbrücken VDM, Müller, 2006. http://deposit.d-nb.de/cgi-bin/dokserv?id=2862127&prov=M&dok_var=1&dok_ext=htm.
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Wiswede, Daniel. "Emotional modulation of memory encoding and performance monitoring." Göttingen Sierke, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=2984215&prov=M&dok_var=1&dok_ext=htm.
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Makowka, Katja. "Seniorenwirtschaft in der Emscher-Lippe-Region Potentiale für eine regionale Entwicklung?" Berlin Münster Lit, 2006. http://deposit.d-nb.de/cgi-bin/dokserv?id=2976404&prov=M&dok_var=1&dok_ext=htm.
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Makowka, Katja. "Seniorenwirtschaft in der Emscher-Lippe-Region : Potentiale für eine regionale Entwicklung?" Berlin ; Münster Lit, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=2976404&prov=M&dokv̲ar=1&doke̲xt=htm.
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Grellert, Marc. "Immaterielle Zeugnisse Synagogen in Deutschland ; Potentiale digitaler Technologien für das Erinnern zerstörter Architektur." Bielefeld Transcript, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=2960353&prov=M&dok_var=1&dok_ext=htm.
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Klauke, Ines. "Potentiale einer umweltfreundlichen Beschaffung in Kommunen aus marktorientierter Sicht am Beispiel von Ökostrom." Dresden TUDpress, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=2946445&prov=M&dok_var=1&dok_ext=htm.
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Belge, Burak. "Urban Archaeological Issues And Resources In Izmir Historic City Centre: An Exploratory Case Study." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606886/index.pdf.
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In Turkey, the majority of the historic city centres have been continuously occupied since early ages onwards and where still occupation exists. The multi-layered structure of historic centres both can indicate the historical continuity of cities and enhance urban consciousness, if urban archaeological resources are handled effectively into planning process. However, the recent policies and strategies don’
t allow the handling of urban archaeological resources, especially invisible sub-soil resources, into planning and decision-making process. In this thesis, it is aimed to formulate a basic methodological framework for the handling of urban archaeological resources into planning process of historic city centres in Turkey. Therefore, the study is handled in two parts
a conceptual methodological framework part and an exploratory case study.In the conceptual part, a basic equation is studied to research the factors on the conservation and evaluation of real urban archaeological potential. Then, the methodological framework is examined in detail in izmir Historic City Centre that has been inhabited since 324 B.C. Consequently, the terms of equi-property areas, which are used to define ideal potential of archaeological resources, and urban archaeological character zones, which are described as the basic units of planning and conservation policies, are developed to determine exact management strategies for urban archaeological resources.
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Sauter, Justin. ""Professional Services" im Fokus der Neuen Institutionenökonomik und der Unternehmensethik : eine Untersuchung der Notwendigkeit sowie der Möglichkeiten und der Potentiale einer moralsensitiven Erbringung von Professional Services /." München ; Mering : Hampp, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=2874500&prov=M&dokv̲ar=1&doke̲xt=htm.
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Sauter, Justin. ""Professional Services" im Fokus der neuen Institutionenökonomik und der Unternehmensethik eine Untersuchung der Notwendigkeit sowie der Möglichkeiten und der Potentiale einer moralsensitiven Erbringung von Professional Services." München Mering Hampp, 2006. http://deposit.d-nb.de/cgi-bin/dokserv?id=2874500&prov=M&dok_var=1&dok_ext=htm.
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Loulergue, Patrick. "Caractérisation In-Situ de dépôts formés en filtration membranaire de suspensions particulaires et de biofluides : intéraction entre structure locale et performances du procédé." Thesis, Toulouse, INSA, 2012. http://www.theses.fr/2012ISAT0046/document.
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Le colmatage membranaire demeure l’un des verrous majeurs des bioréacteurs à membrane (BAM). Ces travaux visent à apporter une contribution à la compréhension de la dynamique de structuration de dépôts complexes formés lors de la filtration frontale de (bio)fluides et son impact sur les performances de filtration. Pour cela, différents outils permettant la mesure in-situ des propriétés structurelles locales des dépôts ont été utilisés de manière à pouvoir relier ces propriétés aux performances globales de filtration. Les propriétés électrocinétiques des dépôts ont également été étudiées. Deux méthodes, l’une optique et l’autre acoustique, ont été utilisées pour caractériser les propriétés structurelles locales des dépôts (épaisseur, cinétique de croissance). Dans un premier temps, les épaisseurs obtenues par les méthodes optiques et acoustiques ont été comparées. Il a été montré que, dans le cas de dépôts peu poreux, les deux méthodes conduisent aux mêmes épaisseurs de dépôts. Dans le cas de dépôts plus poreux, ces deux méthodes permettent l’obtention de données complémentaires à deux niveaux de profondeur différents au sein du dépôt. L’influence des conditions opératoires sur la structuration de dépôts de particules modèles a ensuite été étudiée. Grâce à la méthode optique il a été montré que, quelles que soient les conditions opératoires, il existe une variation temporelle des propriétés du dépôt. De plus, une répartition non homogène du dépôt à la surface de la membrane peut également exister, favorisée par de faibles répulsions entre particules. Enfin, l’applicabilité des différentes méthodes au cas des biofluides issus de BAM a été évaluée. La structure de dépôts complexes constitués lors de la filtration de ces biofluides a ensuite été étudiée. La compressibilité des dépôts, mise en évidence à l’échelle globale par suivi des performances de filtration, a également été observée à l’échelle locale : l’épaisseur du dépôt décroît avec une augmentation de la PTM. De plus, à l’échelle locale, une variabilité spatiale des propriétés du dépôt a été mise en évidence. Afin de contrôler la compressibilité des dépôts l’impact de l’ajout de particules au sein du biofluide a été évaluéMembrane fouling is one of the major drawbacks of membrane bioreactors. This study is thus a contribution to the understanding of the dynamic structuring of complex deposits build-up during dead-end filtration of complex biofluids. Several tools were used to perform in-situ characterization of cake layer structural properties at local scale and to link them to global filtration performances. The electrokinetics properties of the deposit were also investigated. An optical and an acoustic method were used to measure local cake thickness and growth kinetics. The thicknesses given by the two methods were first compared. It was shown that for compact deposits the two different methods lead to the same thickness of the deposit. For more porous deposits, these two methods allow to obtain complementary data at two different depths of the deposits. The influence of operating conditions on cake layer structuring during filtration of modelled particles was evaluated. Using the optical method it was shown that, whatever the operating conditions, the cake structure is not constant in time. Furthermore, a spatial variability of the cake layer thickness might exist especially in the case of weak particle-particle repulsion. Finally, it has been investigated whether the different methods could be applied or not to the case of biofluid filtration. The structural properties of the complex deposits built up during diluted activated sludge filtration were investigated. Cake compressibility was observed at global scale by a monitoring of process performances and was also observed at local scale: cake thickness decreases as TMP increases. Furthermore, at local scale, a spatial variability of deposit structure was found. Particle addition into the biofluid was assessed in order to mitigate compressibility effects
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Saygili, Gokhan. "Liquefaction potential assessment in soil deposits using artificial neural networks." Thesis, 2005. http://spectrum.library.concordia.ca/8454/1/MR04357.pdf.
Full textAbstract:
In the literature, several simplified methods can be found to assess nonlinear liquefaction potential of soil. Derived from several field and laboratory tests, various procedures, also named as conventional methods, have been developed by utilizing case studies and undisturbed soil samples. In order to examine the collective knowledge built up in the conventional liquefaction methods available in the literature, a General Regression Neural Network (GRNN) model is proposed herein, which incorporates the parameters ignored in the past and accordingly will eliminate the shortcomings of the existing design formulae. Two, separate sets of field data, based on the standard penetration test, SPT, and the cone penetration test, CPT were used to develop the GRNN model. The proposed GRNN model predicted the occurrence/nonoccurrence of soil liquefaction well in these sites. Furthermore, liquefaction decision supported by SPT test results is incorporated into CPT based soil and seismic data. Therefore, the model supports the data conversion of an SPT-to-CPT throughout the liquefaction potential analysis, which believed to be the primary limitation of the simplified techniques. Thus the proposed model provides a viable tool to geotechnical engineers in assessing seismic condition in sites susceptible to liquefaction
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Fassell, Michelle Lee. "Late Quaternary marine deposits, offshore central Texas: Processes controlling geometry, distribution, and preservation potential." Thesis, 1999. http://hdl.handle.net/1911/17263.
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The interplay of sediment supply, accommodation space, and the rate of sea-level rise and fall, determine the thickness and overall extent of offshore deposits along the central Texas shelf. Analysis of near-shore sediment cores suggests that transgressive and highstand shorelines prograded during the Holocene. The preservation of these deposits may be likely given the geometry and distribution of older, offshore shorelines. The Stage 5d and Stage 3 highstand shorelines prograded during an overall sea-level fall. High sediment supply from longshore transport preserved thick, aerially extensive shoreline deposits.
Fluvial incision varied significantly during lowstand Stage 2. As the rate of base-level fall increased from Stage 3 to 2, low sediment supply rivers incised narrow, shallow channels with no deltaic deposition, whearas sediment bypass and deeper incision prevailed for the high sediment supply rivers.
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Tai, Lee Tung, and 李東泰. "Study on Liquefaction Potential of Saturated Sand Deposits Using both Regular and Seismic Loading Pattern." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/61371936438819914241.
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Farmer, Lucian P. "Trace element characteristics of zircon : a means of assessing mineralization potential of intrusions in northern Nevada." Thesis, 2012. http://hdl.handle.net/1957/36276.
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Oxidized hydrous intermediate composition magmas are responsible for porphyry copper (Cu ±Mo ±Au) deposits and epithermal Au ore deposits formed globally in the shallow crust (Sillitoe, 2010; Seedorff et al., 2005). Recently, zircon geochemistry has been used to characterize both productive and barren intrusions associated with porphyry Cu-Au ore deposits. Zircon composition differs slightly between the two intrusive groups, and researchers have proposed that zircon in productive intrusions has crystallized from a relatively more oxidized melt compared to barren intrusions (Ballard et al., 2002; Muñoz et al., 2012). Zircon rare earth elements record anomalies in Ce and Eu contents that allow estimation of the ratio of oxidized versus reduced species, i.e. Ce⁴⁺/Ce³⁺ (Ce[superscript IV]/Ce[superscript III]) and Eu³⁺/Eu²⁺ (Eu/Eu*)[subscript CN].
This study focuses on understanding the compositions of Eocene magmas associated with sediment hosted Carlin gold deposits and the gold-copper ores of the Battle Mountain porphyry Cu-Au-skarn district in northern Nevada. Zircon trace element composition was analyzed using LA-ICP-MS and SHRIMP-RG to determine differences between mineralizing and non-mineralizing intrusions in northern Nevada and to compare these compositions with known porphyry Cu-Au type magmas. These zircon and rock compositional data was then used to test the hypothesis of a magmatic origin of the Carlin type gold deposits (Muntean et al., 2011).
Zircon U-Pb ages were calculated using multiple SHRIMP-RG spot analyses of each sample for two Carlin biotite porphyry dikes, two Battle Mountain porphyry dikes and the granodiorite of the Copper Canyon stock. The new U-Pb age dates for Carlin porphyry dikes are 38.7 ± 0.5 Ma and 38.8 ± 0.4 Ma. The age of the Copper Canyon stock is 38.0 ± 0.7 Ma, and the age of the Battle Mountain porphyry dikes are 40.2 ± 0.4 Ma and 41.3 ± 0.4 Ma. The Carlin dike ages are the same age, within uncertainty, with previous studies conducted (Mortensesn et al., 2000).
The productive porphyry dikes from the Battle Mountain district have Ce(IV)/Ce(III) ratios of 500 to 10000 and a wide range of (Eu/Eu*)[subscript CN] values between 0.3 and 0.7 respectively. Carlin porphyry dikes have Ce(IV)/Ce(III) values between 100 and 1000, and a more limited (Eu/Eu*)[subscript CN] range of 0.5 to 0.7. Barren Eocene intrusions at Harrison Pass and Caetano have much lower Ce(IV)/Ce(III) ratios that range from 20 to 500, and have a very large span of (Eu/Eu*)[subscript CN] from 0.03 to 0.6.
Calculated Ce(IV)/Ce(III) and (Eu/Eu*)[subscript CN] of zircon of this study illustrate a distinction between productive and barren intrusions in northern Nevada, and demonstrate a geochemical link between porphyry type magmas and dikes associated with Carlin type gold deposits. These ratios may provide a useful means of evaluating potentially economic geologic terranes and serving as a method to infer relative oxidation state of zircon bearing intrusive rocks.Graduation date: 2013
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Akintola, George Oluwole. "Evaluation of major clay deposits for potential industrial utilization in Vhembe District Municipality, Limpopo Province of South Africa." Diss., 2018. http://hdl.handle.net/11602/1128.
Full textAbstract:
MESMEGDepartment of Mining and Environmental Geology
Vhembe District has several clay deposits which are traditionally use for clay products such as burnt bricks without taking into account the chemical and mineralogical characteristics of clay being used. The ever-increasing market demand for these clay products cannot be met with the traditional method of clay utilization due to the paucity of scientific information on properties of the clay in the area. Consequently, there is a need to gain better understanding of the characteristics of the clay in Vhembe District and to establish the suitability of the variety of clay for different purposes. The current study was undertaken to better understand the compositional relationship between the clay deposits and surrounding rocks present in the study area. It further aimed at characterizing the clay deposits on the basis of chemical, mineralogy, physical, mechanical, thermal and micro structural properties with a view of evaluating the clays for possible industrial use. A total of thirty-nine clay and rock samples were collected from thirteen different locations across the Vhembe District. Thirteen representative samples from each location were obtained after thorough mixing until homogenization was attained and then quartered for subsequent analyses. The mineralogical and chemical characteristics of the clay and rock samples were determined using XRD and XRF respectively. Thin-sections of the rock samples were prepared and examined under petrographic microscope to better understand the mineral assemblages present in the rocks. The thermal and micro structural properties of the clays were determined using DTA-TGA and SEM analyses and the physical properties which include colour, cation exchange capacity (CEC) and soil pH were assessed. The particle distribution and Atterberg limits tests of the clay samples were also conducted in order to establish their mechanical properties. The petrographic results showed that the clay deposits exhibited an intense weathering and sedimentation processes which incorporated detrital minerals from the surrounding rock units. The rock units which include basalt, granodiorite, gneiss and quartzofeldspathic gneiss were found to be differentiated from subalkaline and/or tholeiitic magmatic composition. Although the value of SiO2 content in rock samples was higher when compared with clay samples, it indicated an ongoing desilicication and allitization processes. The high values of chemical index of alteration (CIA), low values of K/Cs (<6200), Ce* normalized value and higher values of LILE enrichment in the clay deposits indicated oxidizing environments during period of deposition. v The mineralogical composition of the studied clayey deposits showed that smectite (8.25 - 29.32%), kaolinite (14.91 - 59.26%) and chlorite (5.94 -16.54%) were present as clay minerals although associated with other non-clay minerals such quartz, plagioclase, talc and geothite. The chemical composition results revealed high silica and alumina content in most studied clay samples. Their fluxing oxides which include K2O, Na2O, CaO, and MgO, varied slightly from 0.06% to 1.78% in abundance while the Fe2O3 and TiO2 contents in most samples averages at 9.2% and 1.3% respectively. The plasticity index of the studied deposits ranged from 9.50 to 62.00% while liquid limit ranged from 31.34 to 73.62%. The microanalysis using SEM indicated that the microstructure framework of most studied clay exhibited a porous skeleton structure owing to numerous tiny voids. The composite results of SEM and CEC analyses suggested their possible application in water filter and chemical fertilizer industries since they provided passage for water and soil cations transmission. The particle size distribution demonstrated that the studied soils have clayey silt texture with wide range coverage of the well graded and sorted particle sizes. Compressibility and plasticity properties were found to be high in Mukondeni, Mashamba-1, Mashamba-2 and Mashamba-3 clay samples. The thermal behavior of Mukondeni, Mashamba-1, Mashamba-2 and Mashamba-3 samples showed relatively high shrinkage (>9%). The high shrinkage percentage suggests the preponderance of smectite minerals. Other samples which are rich in kaolinite and chlorite minerals exhibited low shrinkage (<2%). The drying trends of the studied clay suggest their suitability for fast drying processes like soft and hard refractoriness, sanitary wares and ceramics. Empirical assessment of most studied clay showed their suitability for pottery-making and manufacturing of roofing tiles and masonry bricks.
NRF
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Sandersen, Andrea. "A review of the coalbed methane potential of South Africa's coal deposits and a case study from the north-eastern Karoo basin." Thesis, 2012. http://hdl.handle.net/10210/4510.
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M.Sc.The potential target areas for coalbed methane in South Africa are reviewed and a case study based on borehole data from the north-eastern Karoo basin was undertaken. The Early Permian coal seams of the Karoo Supergroup occur in several discrete sedimentary basins in South Africa, of which the Karoo basin is the largest. Using screening criteria based on geological, petrographical and analytical data some of the coal deposits can be excluded as potential coalbed methane producers. These include the Molteno Coalfield, large parts of the Karoo basin coal deposits and some of the Northern Province's coal deposits which are structurally disturbed. The traditional mining areas in the Free State, Witbank and Highveld coalfields are excluded from the coalbed methane study because the target seams occur at less than 200 metres below surface, too shallow for gas retention. Some of the coal seams in the Waterberg Coalfield occur at depths of several hundred metres below surface and these are unlikely to be mined by conventional means. These deep coals may be ideal coalbed methane producers. This regional overview was based on available, published data and two important parameters, permeability of coal and coalbed hydrology are unknown but important factors that will need to be taken into account in any future evaluations. The case study focused on an area close to Amersfoort that has a predicted potential for coalbed methane production. The study utilized 465 borehole descriptions from which isopach maps and geological cross-sections were constructed. Limited samples of borehole core provided lithological information from which a facies analyses was undertaken so as to establish the hydrodynamic origin of each facies types. The main lithofacies associated with the coal seams are mudstones, carbonaceous shales and fine- to coarse-grained sandstone. These data were combined with analyses from limited permeability data, petrographical data and proximate analyses for the Gus and Alfred seams. In addition to the sedimentary rocks, the role of dolerite intrusions was found to be significant as these occur as thick sills and dykes that occur below, within and above the coal seams. These may compartmentalize the seams into secondary targets within the study area. Thick sills overlying the coal zone also increase static loading and may be advantageous with respect to reducing the minimum depthbelow- surface requirements. Potential coalbed methane target areas are identified, although the entire study area is not suitable due to structural displacement of the coal seams, thinning of coal in places and devolatization caused by the dolerites.
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Lusunzi, Rudzani. "Geochemical and mineralogical characterization of gold mine tailings for the potential of acid mine drainage in the Sabie - Pilgrims's Rest Goldfields." Diss., 2018. http://hdl.handle.net/11602/1204.
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MESMEGDepartment of Mining and Environmental Geology
This study entails geochemical and mineralogical characterization of gold tailings of Nestor Mine and Glynn’s Lydenberg Mine of the Sabie-Pilgrim’s Rest goldfields. A total of 35 samples were collected and were analysed for chemical composition (XRF and ICP-MS), mineralogical composition (XRD). In addition, acid-base accounting (ABA) techniques had been conducted to predict the potential for acid mine drainage. Seepage from Nestor tailings dump and water samples from the adjacent Sabie River were also collected and analysed by means of inductively coupled plasma mass spectrometry (ICP-MS) and immediate constituent (IC) -analytical techniques. The study revealed that Sabie-pilgrim’s rest goldfield is characterized by both acid generating and non-acid producing tailings, and this is attributed to variations in the mineralogy of source rocks. Gold occurred within the Black Reef Quartzite Formation in the Nestor Mine and within the Malmani Dolomite in the case of Glynn’s Lydenburg Mine. Mineralogy and bulk geochemical analyses performed in this study showed a clear variation in the chemistry of Nestor Mine and Glynn’s Lydenburg Mine tailings. Predominant oxides in Nestor mine tailings samples are SiO2 (ranging from 66.7-91.25 wt. %; followed by Fe2O3 and Al2O3 (in range of 0.82-15.63 wt. %; 3.21-12.50 wt. % respectively); TiO2 (0.18-10.18 wt. %) and CaO (0.005-3.2 wt. %). Also occurring in small amounts is CaO (0.005-3.2 wt. %), K2O (0.51-2.27 wt. %), MgO (0.005-1.46 wt. %), P2O5 (0.029-0.248), Cr2O3 (0.013-0.042 wt. %) and Na2O (0.005-0.05 wt. %). The samples also contain significant concentrations of As (137-1599 ppm), Cu (34-571 ppm), Cr (43-273 ppm), Pb (12-276 ppm), Ni (16-157 ppm), V (29-255 ppm), and Zn 7-485 ppm). In the Glynn’s Lydenburg Mine tailings SiO2 is also the most dominant oxide ranging between 47.95 and 65.89 w%; followed by Al2O3 (4.31 to 16.19 wt. %), Fe2O3 (8.48 to 11.70 wt %), CaO (2.18 to 7.10 wt. %), MgO (2.74 to 4.7 wt. %). Occurring in small amounts is K2O (1.12-1.70 wt. %), MnO (0.089-0.175 wt. %), P2O5 (0.058-0.144 wt. %) and Cr2O3 (0.015-0.027 wt. %). Arsenic (As), is also occurring in significant amounts (807-2502 ppm), followed by Cr (117-238 ppm), Cu (10-104 ppm), V (56-235 ppm), Ni (45-132 ppm), Pb (13-63 ppm) and Zn (90-240 ppm). Nestor Mine tailings associated with Black Reef Formation mineralization have net neutralizing potential (NPR) <2, hence more likely to generate acid; and their acid potential (AP) ranges 1.56 to 140.31 CaCO3/ton and neutralizing potential (NP) range from -57.75 to -0.3 CaCO3/ton. Glynn’s Lydenburg Mine tailings dump which is vi associated with dolomite mineralization, however, was not leaching acid. Based on acid-base accounting results, these tailings have more neutralizing potential (ranging between 57.6 and 207.88 CaCO3/ton) than acid potential (ranging between 7.5 and 72.1 CaCO3/ton); and their NPR>2, hence unlikely to produce acid. This is confirmed by paste pH which was in the ranges between 7.35 and 8.17. Tailings eroded from Nestor Mine tailings dump were also found to be characterized by high content of metals and oxides, namely, As, Cu, Ni, Pb, V, and Zn with SiO2, Fe2O3 and TiO2. The tailings were observed eroded into the Sabie River where AMD related precipitate (yellow boy) was also observed, indicating further oxidation downstream. Field observations, onsite analyses of water samples and laboratory results revealed that Nestor Mine tailings storage facility discharges acid mine drainage with considerable amounts of Al, As, Cu, Fe, Mn, Zn and SO4 and very low pH exceeding the limit as per South African water quality standards. High concentrations of these metals have toxicity potential on plants, animals and humans. Upon exposure to oxygen and water, tailings from Nestor Mine are more likely to generate acid mine drainage that can cause detrimental effect to the environment and the surrounding communities. Potential pollutants are Fe, Mn, Al, As, Cr, Cu, Ni and Pb. Tailings from Glynn’s Lydenberg showed no potential for acid mine drainage formation.
NRF
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Chih-ping, Kuo, and 郭治平. "A Study on Liquefaction Potential of Alluvial Deposies at Yunlin County, Taiwan." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/85790234869940923190.
Full textAbstract:
碩士國立雲林科技大學
營建工程系碩士班
89
ABSTRACT As located in the mid-west plain of Taiwan, Yunlin County has been under planning, construction and operations of several significant projects for industrial parks, warehouses, and transportations. For instances, No. 6 Naphtha Cracker Complex Project of Formosa Plastics Group in Mailiao Town, Yunlin Offshore Industrial Estate along the western coastline of Shihu and Kouhu Towns, Touliu Industrial Park near the eastern hilly area of Yunlin, High Speed Railway Project and the Second Freeway Project which pass through the County, and the East-West Express Way Project, etc., all of which indicate a prosperous picture of Yunlin County in the near future. Despite the activities mentioned above, there are still plenty lands not used or undeveloped within the area. It can be expected that, as the growth of business and industry, the lands will be highly considered or soon be used for other upcoming projects. The study collected approximately 90 fieldwork reports over a period of about 20 years in the past, which include about 800 borehole logs spread around the entire County. A total of 578 borehole logs had been examined to be correct and useful for the subsequent liquefaction analysis. Three types of liquefaction analysis procedures were adopted, which include: Seed’s Simplified Method (1997 NCEER’s Workshop), Tokimatsu & Yoshimi’s Method (1983), and the new version of Japan Railway Authority’s Method (NJRA, 1996). A weighing technique suggested by Iwasaki (1982) was then used to evaluate the overall liquefaction potential, defined as Liquefaction Potential Index (PL), for the full length of the effective boreholes. In addition, post-liquefaction settlements were estimated based on the procedure proposed by Ishihara (1993), and contours of liquefaction potential and post-liquefaction settlement were generated for the entire study area. Finally, the study compared the conservatism and correctness of the three procedures adopted herein based on the observations of the 1999 Chi-Chi Earthquake which had resulted tremendous liquefaction incidents in Yunlin and Changhua Counties. The results showed that the liquefaction potential for most of Yunlin County (i.e., coastline area: Mailiao, Taishi, Shihu, and Kouho Towns; inlands: Shilo, Huwei, and Tounan Towns) is very high and the calculated post-liquefaction settlements can be up to 40cm, under the design earthquake of the current code. Among the three analysis procedures used in the study, NJRA’s method is more conservative than Tokimatsu & Yoshimi’s Method and Seed’s Method, in terms of the calculated liquefaction potential. However, it was found that NJRA’s analysis appears to be in a better agreement with the observations of liquefaction damages at Yunlin and Changhua Counties during the 1999 earthquake. In order to improve the suitability of usage, the study proposed a correction for Tokimatsu & Yoshimi’s Method and Seed’s Method for their use in Taiwan.
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Wu, Wen-Hui, and 吳雯惠. "The Study on Estimation of Debris Flow Potential and Deposited Volume." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/54211160342548540676.
Full textAbstract:
碩士朝陽科技大學
營建工程系碩士班
94
After the 921 Chi-Chi earthquakes, steep topography, weak geology, and slopeland overuse caused frequent debris flow in mountain areas in which people also suffered from debris flow during plum rains and typhoon seasons. Thirty-four potential debris-flow creeks in the Chen-yu-lan watershed were studied investigated. Debris flow potential and deposited volume were estimated, using the following multi-variable statistical analysis.（1）The effects of topographic, material and rain-related factor on debris flow were studied investigated.（2）Potential analysis was perfomed to yield useful information on the debris flow.（3）Factors of debris flow were studied investigated using cluster analysis.（4）A regression analysis of the deposited volume was performed. In this work study, eight factors that govern debris flow were studied investigated. These were watershed area, form factor, mean slope, river density, landslide area, geological index, effective accumulated rainfall and effective rainfall intensity. Fisher discriminant analysis and artificial neural networks were used to determine: check debris flow. The resulting corrected rate is more accurate than that obtained using any artificial neural network. The analysis results, the formulas of the landslide area (AL) in terms of the watershed area (A) and the landslide area (AL) in terms of the deposited volume (V ) are as follow AL＝0.0063 A 1.21, = 349140 AL0.50. The variables are grouped by cluster analysis, and the effect of each group on debris flow deposited volume relations. This classification is used to determine debris flow size. Deposited volumes are obtained by regression analysis（1）V =156（A）+525（AL）+ 2189（S）– 11576, （2）V =262（A）+ 2489（S）– 39240,（3）V ＝154（A）+527（AL）+1716（S）+235（Re）– 70924.
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Liou, Tzong-Shung, and 劉宗昇. "Excess Pore Pressure Changes of Stabilization of Potentially Liquefiable Sand Deposits Using Gravel Drains." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/97212003733996844500.
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HOU, HUA-SUNG, and 侯華嵩. "Effect of potential windows of electro-deposited manganese-cobalt oxide films on the capacitive behaviors." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/53240574531151662264.
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碩士崑山科技大學
材料工程研究所
105
In this paper, cobalt manganese oxide (CMO) films were deposited on the stainless steel (SS) sheets by cyclic-voltammetric anode deposition method using manganese acetate and cobalt acetate in sodium sulfate electrolyte. The effects of cyclic voltammetric voltage range on the physical and chemical properties and capacitive behavior of the films were investigated. The CMO film on the SS sheet exhibits no X-ray diffraction (XRD) pattern, while the scraped powder from the CMO film indicates a micro-nanocrystalline grain structure of birnessite MnO2 (δ-MnO2).The samples B10, B10, B12, and B14 prepared in the potential range of 0.4-1.0V, 0.4-1.2V, 0.4-1.4V, and 0.4-1.6V, respectively, demonstrate the type Ⅳ adsorption-desorption isotherms and H2 hystereses, indicating that these samples posses mesoporous structures similar to columnar or thin necks and wide bodies. In addition to mesopores, the four samples also feature significant microporous distribution. The specific surface area decreases in order of B14> B10> B12> B16. As the deposition voltage increases from 1.0V to 1.6V, the atomic ratio of cobalt / (cobalt + manganese) increases from about 5.0% of B1 to 6.5% of B16. Due to the highest deposited voltage employed, the B16 sample is suspected to display dissolvation and redeposition of CMO, causing the least pore volume and average pore size. Electron microscopy analyses indicate that the CMO films are all composed of interconnected nnaoflakes creating porous structures which are beneficial for the penetration of electrolytes. The specific capacitances of the four test samples are in the descending order of B14> B10> B12> B16, where the B14 sample has the largest specific capacitance due to the maximum specific surface area and the proper pore structure. However, the B14 sample alos exhibits the least knee frequency and relaxation time frequency as a result of significant diffusion resistance, which is likely attributed to the larger film thickness when compared with other samples. At low scan or cgarging-discharing rates, the pure manganese oxide film shows a specific capacitance close to that of B14, howver, it declines quickly with raising the scan or chcrging-discharging rates. The results indicates that doping cobalt oxide can effectively improve the diffusion of electrolyte within the porous structure can enhance the rate capability of the pseuducapacitors. The CMO composite electrode shows excellent long-term cyclic stability with 100% retention of specific capacitance after 1000 CV cycles with a high scan rate of 0.1V/s.
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Shrestha, Rajendra B. "Evaluation of mineral exploration potential based on the multi-element analysis of stream sediments and mineral deposit modelling, Central Nepal." Thesis, 1991. http://hdl.handle.net/10125/9821.
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