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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

Management of Geohazards at Lihir Gold Mine-Papua New Guinea

Singh, Mohan 11 1900 (has links)
Lihir Gold Mine in Papua New Guinea is one of the largest gold mines in the world situated in a seismically sensitive zone. The gold deposit is located in an extinct volcano in close proximity to the sea shore and presents a series of geohazards. Some geohazards are uncommon and include: geothermal outbursts, cavities, water inrush and earthquake/ tsunami. After a major multi-batter (5 benches high) slope failure that occurred on the 1st of October 2009, a team of engineers, lead by the author investigated the incident and made series of recommendations. Arising out of these recommendations, a comprehensive Geohazard Management Plan was formulated by revisiting, revising and putting together all the individual geohazard management plans as a single document. This thesis describes the outcomes of the investigation and presents an overview and systematic approach in formulation of the Geohazard Management Plan, apart from a summary of the gaps that were identified in the existing system, major contributions that were made as well as the expected improvements and constraints in managing these geohazards. / Mining Engineering
222

Tsunamikatastrofen : hjälpinsatser, massmedia och vanligt folks tankar

Eriksson, Anna January 2006 (has links)
De större hjälporganisationerna organiserade sina hjälpinsatser på liknande sätt under tsunamikatastrofen. Oftast kom en appell från någon systerorganisation. Därefter gjordes en sammanställning av hjälpbehovet, innan man skickade det som behövdes till området, vare sig det var material eller kunnig personal. Det var sedan systerorganisationen som styrde arbetet på plats eftersom de känner bäst till sitt lands samhällsstruktur. Risken för kulturkrockar minskade genom att de utländska biståndarbetarna kunde vända sig till sin systerorganisation för råd och stöd i frågor rörande den kultur de befann sig i. Medias roll under och efter katastrofen har varit både informativ och granskande, men den kunde också vara spekulativ och osaklig. Man kan se en viss skillnad mellan morgontidningarna och kvällstidningarna. Kvällstidningarna verkade i högre grad vilja försöka sälja lösnummer på människors lidande och var mer individfokuserad än morgontidningarna. Morgontidningarna speglade tsunamin mer ur ett helhetsperspektiv. Jag fann också att morgontidningarna oftare hänvisade till källorna än kvällstidningarna. Under tsunamikatastrofen väcktes existentiella frågor. Jag fann att många av dessa tankar handlade om livets förändlighet, hur snabbt allt kan ändras. Många tankar kretsade kring familjen. Detta kom fram både i enkätundersökningen och hos de som arbetade med katastrofen. Tankarna kring tsunamikatastrofen verkar dock idag handla mer om hur man kan få till stånd bättre och snabbare krisberedskap, än om de existentiella tankarna, som var mer dominerande direkt efter att katastrofen inträffat. Det unika med tsunamikatastrofen var att den väckte ett starkt engagemang bland folk som på olika sätt ville hjälpa till. Nu verkar det dock som att tsunamin börjat blekna för de flesta. Man kan se på nya insamlingar olika hjälporganisationer gjort att engagemanget inte är så stort som under tsunamikatastrofen.
223

南極から美ら海まで : 14C年代測定をはじめて45年

Omoto, Kunio, 小元, 久仁夫 03 1900 (has links)
第23回名古屋大学年代測定総合研究センターシンポジウム平成22(2010)年度報告
224

"Ett lugnt hörn när det är kaos i världen" : en studie om varför barnprogrammet Bolibompa ser ut som det gör under och dagarna efter en katastrof

Isaksson, Linnea, Jeppsson, Elise January 2008 (has links)
This study intends to examine why the Swedish children’s programme Bolibompa is produced the way it is during a larger catastrophe. Our intention was to find out how the editorial staff, in the children’s department in the public service television of Sweden (SVT),was handling the Estonia disaster, the September 11 attacks and the Asian Tsunami. To accomplish that, we first had to find out how the children’s programme looked during these catastrophes and also understand how the editorial staff was working with children’s programme during ordinary days. To achieve our purpose we have been interviewing five persons from SVT, who was involved in producing the children’s programme during these three catastrophes. The method we used was qualitative research interview and theories of socialisation, media effects, social responsibility and theories of rhetoric mass media guided our study. We found out that the editorial staff was producing the children’s programme differently during each catastrophe. When the Estonia disaster occurred, the children’s programme was delayed because of extended news. Next to the children’s programme a host was talking directly to the children trying to explain the accident. The day after the September 11 attacks the host of the children’s programme was discussing the catastrophe with invited guests in the TV studio. The editorial staff thought that many children were frightened at the time and that explains why they decided to keep a conversation. During the Asian Tsunami, SVT was broadcasting a Christmas special, and the children’s programmes weren’t changed at all,mostly because a break in the Christmas series would cause a lot of problems.
225

Management of Geohazards at Lihir Gold Mine-Papua New Guinea

Singh, Mohan Unknown Date
No description available.
226

Neotectonics, Seismic and Tsunami Hazards, Viti Levu, Fiji.

Rahiman, Tariq Iqbal Hamid January 2006 (has links)
Viti Levu, the main island of Fiji, is located in a seismically active area within the Fiji Platform - a remnant island arc that lies in a diffuse plate boundary zone between the Pacific and Australian tectonic plates in the southwest Pacific. The southeast coast of Viti Levu is a highly developed and populated part of Fiji and is vulnerable to the effects of large earthquakes that are expected to occur both onshore and offshore. The structural framework and the origin of seismicity within the Fiji Platform, as well as the seismic and tsunami hazards of central and southeast Viti Levu are investigated. The upper crust of southeast Viti Levu is dissected by several intersecting fault/lineament zones. These are mapped from remote sensing imagery of the surface (topography, radar, and aerial photos) and of the basement (magnetic), and have been subject to rigorous statistical tests of reproducibility and verification with field mapped fault data. Lineaments on the various imagery correlate with faults mapped in the field and show spatial continuity between and beyond mapped faults, thereby providing a fuller coverage of regional structural patterns than previously known. Some fault/lineament zones extend beyond the coastline to the offshore area of southeast Viti Levu. Here high resolution SeaBAT 8160 multibeam bathymetry data and seismic reflection data show that the fault zones occur along, and exert control on the locations of a number of linear submarine canyons. The morpho-structural expression of these canyons are contiguous with fault controlled physiographic features mapped on the nearshore marginal shelf (rectilinear bays and peninsulas, reef passages) and on land (fault valleys, slope and drainage alignments forming lineaments). The canyons are considered to have developed from several cycles of downslope incising and infilling events, whilst their positions were still primarily controlled by zones of weakness created by the fault zones. The principal fault sets in southeast Viti Levu represent generations of regional tectonic faulting that pervaded the Fiji Platform during and after disruption of the proto Fijian arc in the Middle to Late Miocene. These fault sets combine to form a complex network of interlocking faults creating a fault mesh that divides the upper crust into a number of fault blocks ranging from ~2 to 30 km. It is inferred that the fault mesh evolved throughout the Neogene as a response to the anticlockwise rotation of the Fiji Platform through progressive development of different fault sets and intervening crustal block rotations. Regional tectonic deformation is presently accommodated in a distributed manner through the entire fault mesh. Low magnitude earthquakes (<M4) occur regularly and may represent ruptures along short linking segments of the fault mesh, while infrequent larger earthquakes (>M4) may result from complex rupture propagation through several linking fault segments of the mesh that lie close to optimum stress orientations. This interpreted model of distributed deformation through the fault mesh for southeast Viti Levu is inferred to be characteristic of the style of active deformation that occurs throughout the entire Fiji Platform. Seismic activity is primarily responsible for triggering submarine landslides that occur on the southeastern slope of Viti Levu. These slides typically occur on the outer barrier reef edge, as well as in submarine canyon heads and walls, and in the mid slope areas. They are characteristically translational and lack bathymetric evidence for displaced masses. Morphometric analysis and empirical modelling, show that slides triggered at shallow water depths, within 5 km of the coastline, at the outer barrier reef edge and submarine canyon heads, produce the largest near-field tsunami amplitudes. Such slides are interpreted to represent a significant local tsunami hazard. A detailed case study of the destructive 1953 Suva tsunami that followed the Ms 6.75 Suva earthquake, reveals that the source of this tsunami was a 60 million cubic metre submarine landslide at the head of the Suva Canyon, 4 km to the WSW of Suva City. A test simulation of this tsunami using the Geowave tsunami generation, propagation and inundation model, closely replicates the wave heights and arrival times recorded in 1953. This simulation also reveals that high variability in tsunami impact over short coastal distances of southeast Viti Levu is attributable to the complex interplay of wave propagation with the barrier reef system, erratic lagoon bathymetry and the irregularly shaped coastline. A predictive simulation using Geowave, based on an incipient failure in the 1953 source area and on a potentially worse case scenario event at or near high-tide, is used to show a maximum vertical run up of at least 4 m and a maximum horizontal inundation level of at least 400 m at the Suva coast. The seismic hazard of five sites on Viti Levu, including Suva City, Navua and Nausori Towns, and the Monsavu and Nadarivatu dam sites, is evaluated using a deterministic approach, and seven newly identified crustal fault earthquake source structures. The maximum magnitudes interpreted for these structures, estimated using empirical relationships, range from Mw 6.8 to 7.6. The Suva Canyon Fault, the Naqara Fault, the Mavuvu/Fault Lineament Zone and the Nasivi Fault provide the controlling maximum credible earthquakes (CMCE) at all the five sites. The CMCE peak ground acceleration values for Suva City range from 0.4g to 0.6g, for Nausori Town from 0.18g to 0.2g, for Navua Town from 0.27g to 0.32g, for Monasavu from 0.39g to 0.42g, and for Nadarivatu from 0.23g to 0.33g. The horizontal spectral accelerations at a period equal to 0.2 seconds, calculated using the CMCEs, are comparable to accelerations derived by probabilistic methods that have return periods between 50 and over 1000 years.
227

Modelling of tsunami generated by submarine landslides

Sue, Langford Phillip January 2007 (has links)
Tsunami are a fascinating but potentially devastating natural phenomena that have occurred regularly throughout history along New Zealand's shorelines, and around the world. With increasing population and the construction of infrastructure in coastal zones, the effect of these large waves has become a major concern. Many natural phenomena are capable of creating tsunami. Of particular concern is the underwater landslide-induced tsunami, due to the potentially short warning before waves reach the shore. The aims of this research are to generate a quality benchmark dataset suitable for comprehensive comparisons with numerical model results and to increase our understanding of the physical processes involved in tsunami generation. The two-dimensional experimental configuration is based on a benchmark configuration described in the scientific literature, consisting of a semi-elliptical prism sliding down a submerged 15° slope. A unique feature of these experiments is the method developed to measure water surface variation continuously in both space and time. Water levels are obtained using an optical technique based on laser induced fluorescence, which is shown to be comparable in accuracy and resolution to traditional electrical point wave gauges. In the experiments, the landslide density and initial submergence are varied and detailed measurements of wave heights, lengths, propagation speeds, and shore run-up are made. Particle tracking velocimetry is used to record the landslide kinematics and sub-surface water velocities. Particular attention is paid to maintaining a high level of test repeatability throughout the experimental process. The experimental results show that a region of high pressure ahead of the landslide forces up the water over the front half of the landslide to form the leading wave crest, which propagates ahead of the landslide. The accelerating fluid above, and the turbulent wake behind, the moving landslide create a region of low pressure, which draws down the water surface above the rear half of the landslide to form the leading trough. Differences in the phase and group velocities of the components in the wave packet cause waves to be continually generated on the trailing end of the wave train. The downstream position that these waves form continually moves downstream with time and the wave packet is found to be highly dispersive. The interaction of the landslide pressure field with the free surface wave pressure field is important, as the location of the low pressure around the landslide relative to the wave field acts to reinforce or suppress the waves above. This has a substantial effect on the increase or decrease in wave potential energy. When the low pressure acts to draw down a wave trough, the wave potential energy increases. When the low pressure is below a wave crest, it acts to suppress the crest amplitude, leading to an overall decrease in wave potential energy. Measurements of the efficiency of energy transfer from the landslide to the wave field show that the ratio of maximum wave potential energy to maximum landslide kinetic energy is between 0.028 and 0.138, and tends to increase for shallower initial landslide submergences and heavier specific gravities. The ratio of maximum wave potential energy to maximum landslide potential energy ranges between 0.011 and 0.059 and tends to be greater for shallower initial submergences. For two experimental configurations the ratio of maximum wave potential energy to maximum fluid kinetic energy is estimated to be 0.435 and 0.588. The wave trough initially generated above the rear end of the landslide propagates in both onshore and offshore directions. The onshore-propagating trough causes a large initial draw-down at the shore. The magnitude of the maximum draw-down is related to the maximum amplitude of the offshore-propagating first wave trough. A wave crest generated by the landslide as it decelerates at the bottom of the slope causes the maximum wave run-up observed at the shore. A semi-analytical model, based on inviscid and irrotational theory, is used to investigate the wave generation process of a moving submerged object in a constant depth channel. The simplified geometry allows a variety of phenomena, observed during the experimental tests, to be investigated further in a more controlled setting. The variations in the growth, magnitude, and decay of energy as a function of time is due the interaction of the pressure distribution surrounding the moving slider with the wave field, in particular, the leading crest and trough. The largest energy transfer between slider kinetic energy and wave potential energy occurs when there is prolonged interaction between the slider's low pressure region and the leading wave trough. The generation of onshore propagating waves by a decelerating landslide is confirmed, and the magnitude of the maximum wave run-up is found to be dependent on the magnitude of the slider deceleration. The model also shows that slides with Froude number close to unity convert substantial amounts of energy into offshore propagating waves. The onshore propagating wave potential energy is not as sensitive to Froude number. A further result from the model simulations is that the specific shape of the slider has only a minor influence on the wave response, provided the slider's length and area are known. A boundary element model, based on inviscid and irrotational theory, is used to simulate the laboratory experiments. Model predictions of the wave field are generally accurate, particularly the magnitude and range of wave amplitudes within the wave packet, the arrival time of the wave group, the amplitude of the run-up and run-down at the shore, the time the maximum run-down occurs, and the form and magnitude of the wave potential energy time history. The ratios of maximum wave potential energy to maximum slider kinetic energy are predicted to within ± 29%. The model predictions of the crest arrival times are within 3.6% of the measured times. The inability of the inviscid and irrotational model to simulate the flow separation and wake motions lead to a 45% under prediction of the maximum fluid kinetic energy. Both the semi-analytical and BEM models highlight the need for the correct specification of initial slider accelerations in numerical simulations in order to accurately predict the wave energy.
228

Evaluation du risque tsunamique sur le littoral atlantique marocain

Mellas, Samira 03 December 2012 (has links) (PDF)
Ce travail a pour objectif d'évaluer le risque de tsunami sur le littoral atlantique marocain au moyen d'une approche intégrée, menée sur la base de scénarios de risque, multiscalaires, combinant de la modélisation numérique de l'alea, une évaluation spatiotemporelle des enjeux, et des critères de vulnérabilité physique et humaine. L'étude s'articule en deux phases. Une première phase consiste à évaluer à l'échelle régionale, l'exposition du littoral atlantique marocain au risque de tsunami, en développant une démarche méthodologique de mesure de l'exposition au risque de tsunami basée sur une cartographie intégrant des paramètres d'aléa issus de la modélisation numérique d'un tsunami similaire à celui de 1755 et des bases de données régionales sur l'occupation du sol. Elle aboutit à un jeu de géo-indicateurs de risques agrégés sur plusieurs mailles territoriales (communale et mailles de 5 km de côté) qui permet de dresser une analyse comparative de ce risque à l'échelle du Maroc. Une seconde phase porte sur le risque de pertes humaines en cas de tsunami majeur sur la ville d'El Jadida, exprimé au moyen de géo-indices de risque. La vulnérabilité humaine y est exprimée par une probabilité de décès. Ces probabilités sont données par des matrices fondées sur les données de la submersion marine issues de la modélisation numérique et des critères de vulnérabilité déterminés au moyen de courbes d'endommagement empiriques. Les indices de risque obtenus intègrent la variabilité spatio-temporelle de la répartition de la population au pas horaire pour deux saisons. [etc.]
229

Change and Continuity : Tracing the structure of the Swedish crisis management system on a national level by its advocacy coalitions 2001 - 2014

Mörner, Philip January 2014 (has links)
This essay is an analysis of the Swedish crisis management, as a policy subsystem using the Advocacy Coalition Framework. By applying a Causal Process Tracing method, the main issues of division within the policy subsystem will be examined, and the effects of the 2004 South East Asian tsunami as an incitement of policy change. The major finding is that the reforms that followed the tsunami investigations, to a large extent were planned prior to the tragic event, the main changes seem to have been halted by the 2006 election and change of Office. The cross-party coalitions that were found have theoretical implications for the ACF research.
230

Ecological and social response of the coral reefs of Mu Koh Surin Marine National Park, Thailand, and Phuket's diving industry to the 2004 Indian Ocean tsunami

Main, Michiru Alexa 22 December 2007 (has links)
The 2004 Indian Ocean tsunami created a catastrophic disturbance at several scales along the entire Andaman Sea coast. As the first large-scale tsunami occurring in recent history, this event provided a unique opportunity to use modern instrumentation and in situ observation to study tsunami dynamics and effects on coastal systems. Along Thailand’s coast, consequences of this disturbance were highly variable in space and time, with pronounced changes to certain coral reefs and human communities. This thesis outlines two case study-based research projects designed to gain some understanding of the ecological and social dynamics of the tsunami in Thailand. From a Geographical perspective, responses to this massive disturbance may support an incentive-based direction for marine conservation in Thailand. The first project occurred within Mu Koh Surin Marine National Park, Thailand. Variability in the physical response of fringing hard coral reefs to the tsunami was examined using SCUBA surveys. Patterns in variability were distinct from typical hard coral responses during tropical storms suggesting differences in the nature of these hydrodynamic disturbances. Coral colony morphologies and reef shape mainly did not influence variability in tsunami response; however, unique effects were observed on reef slopes over 45°. There was no detected influence of reef depth. Variability in effects based on the spatial location of reefs was observed: proximity to bathymetrical constrictions accounted for substantial variability, while reef aspect did not. Overall, just over 10% of sampled reef area was affected, with evidence of rapid coral recovery in the form of tissue re-growth and apical skeletal growth within four months of the event at most sites. The second project explored the effects of the tsunami on Phuket’s diving industry. The response of industry members and recreational divers to tsunami effects was examined using interviews and questionnaires as well as observational dives with dive guides and clients on chartered trips during the 2004-5 post-tsunami diving season. A short-term reduction in the number of diving companies and diving tourism in Phuket was observed immediately following the tsunami; this can be attributed to terrestrial damage and trip cancellations. Although there were expectations for high levels of dive site damage, most recreational divers did not perceive any damage on dive sites in 2005 – even while diving on surveyed sites with as much as 76-100% of reef area reportedly affected. This low rate of perception may be partially explained by diving ability, but was more likely due to site variability and variability in tsunami response within dive sites allowing guides to preferentially avoid acutely damaged areas. During the post-tsunami low tourism period, industry members contributed substantial resources to rescue, relief and restoration efforts along Thailand’s Andaman Sea Coast. Industry members also participated in several government and university-led tsunami monitoring and rehabilitation efforts. While measurable changes to Phuket’s diving industry seem to have been short-term, this response of industry members to the event may have increased potential for long-term collaboration with government and universities. Enhanced communication among these parties could facilitate future incentive-driven industry contributions toward marine conservation in Thailand.

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