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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.
41

Valuation and hedging of Himalaya option

Shao, Hua-chin 19 September 2007 (has links)
The first option has been publicly traded for more than 30 years. With the progress of time, despite the European option is still the exchange-traded option. But evolved through the years, the European option has not meet people's needs, so exotic option was born. Similarly, the pricing model, from the traditional closed-form solution (under the Black-Scholes assumption), now commonly used binomial trees, finite difference, or by using the Monte Carlo simulation. The main impact of the following factors: the first, with the complexity of the option contract - from single asset to multi-assets, from the plain vanilla option to the path-dependent option, it is more difficult to find the closed-form solution of the option. Second, with the development of personal computers, making numerical computing is no longer a difficult task. It is precisely these two front reason, there will be the birth of this article. Himalaya option is also an exotic options. With the multi-assets and path dependent features, we want to find a closed-form solution is very difficult. Under multi-assets situation, the binomial tree and finite difference will be time-consuming calculation. Therefore, this paper is using Monte Carlo simulation of reasons. In this paper, we use Monte Carlo simulation to pricing Himalaya option, which includes several variance reduction techniques used to reduce sample variance. Finally, when pricing completed, we try to do a simple study to option hedging.
42

Neogene epeirogeny and the Iceland Plume

Poore, Heather Rachel January 2008 (has links)
No description available.
43

Tectonometamophic evolution of the Greater Himalayan sequence, Karnali valley, northwestern Nepal

Yakymchuk, Christopher 21 September 2010 (has links)
In the Karnali valley of west Nepal, detailed mapping, thermobarometry, quartz-petrofabrics, vorticity analysis, and thermochronology delineate three tectonometamorphic domains separated by structural and metamorphic discontinuities. The lowest domain, the Lesser Himalayan sequence, is weakly metamorphosed and preserves evidence of primary sedimentary features and a polydeformational history. The Greater Himalayan sequence (GHS) is pervasively sheared and metamorphosed and overlies the Lesser Himalayan sequence along the Main Central thrust. The Greater Himalayan sequence is sub-divided into two tectonometamorphic domains that display contrasting metamorphic histories. The lower portion of the Greater Himalayan sequence contains garnet- to kyanite-grade rocks whose peak metamorphic assemblages developed during top-to-the-south directed shear and a metamorphic pressure gradient that increases up structural section. The upper portion of the Greater Himalayan sequence contains kyanite and sillimanite-grade migmatites that preserve polymetamorphic assemblages and a metamorphic pressure gradient that decreases up structural section. The upper and lower portions of the Greater Himalayan sequence are separated by a metamorphic discontinuity that roughly coincides with the bottom of the lowest migmatite unit. Vorticity estimates indicate roughly equal contributions of pure and simple shear during deformation of the upper and lower portions of the GHS. Quartz petrofabrics suggest deformation temperatures are equivalent to peak metamorphic temperatures in the lower Greater Himalayan sequence. These observations are consistent with channel flow tectonic models whereby the upper portion of the Greater Himalayan sequence is ductily extruded to the south while ductily accreting the subjacent lower portion of the Greater Himalayan sequence across a metamorphic discontinuity. 40Ar/39Ar thermochronology indicates Miocene homogeneous cooling of the Greater Himalayan sequence. Cooling rates of the GHS and the homogeneous cooling profile suggest east-west extensional exhumation followed peak-metamorphism and south-directed shearing and supports the hypothesis of the southeast propagation of the Gurla-Mandhata-Humla fault system into the Karnali valley. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2010-09-20 09:23:07.103
44

From cessation of south-directed mid-crust extrusion to onset of orogen-parallel extension, NW Nepal Himalaya

NAGY, CARL 25 September 2012 (has links)
Field mapping and, structural, microstructural, and chronological analyses confirm the existence of a segment of the Gurla-Mandhata-Humla fault, an orogen-parallel strike-slip dominated shear zone in the upper Karnali valley of northwestern Nepal. This shear zone forms the upper contact of, and cuts obliquely across the Greater Himalayan Sequence (GHS). Data from this study reveal two phases of GHS deformation. Phase 1 is characterized by U-Th-Pb monazite crystallization ages (~26–12 Ma, peak ~18–15 Ma), consistent with typical Neohimalayan metamorphic ages, and the final stages of south-directed extrusion of the GHS. Phase 2 is characterized by south-dipping high-strain foliations and intensely developed ESE-WNW trending, shallowly plunging mineral elongation lineations, indicating orogen-parallel extension. Thermochronology of muscovite defining these fabrics implies that the area was cooling and experiencing orogen-parallel extension by ~15–9 Ma. Mineral deformation mechanisms and quartz c-axis patterns of these fabrics record a rapid increase in temperature from ~350°C along the shear zone, to ~650°C at ~2.5 structural km below the shear zone. Such temperature gradients may be remnants of telescoped and/or flattened isotherms generated during south-directed extrusion of the GHS. Overprinting ESE-WNW fabrics record progressive deformation of the GHS at lower temperatures. Progressive deformation included a significant component of pure shear, as indicated by symmetric high-temperature quartz c-axis fabrics and a lower-temperature vorticity estimate (~59% pure shear). A transition in c-axis fabrics from type I to type II cross-girdles at ~ 1.2 km below the fault could indicate a transition from plane strain towards constriction. Together, these data suggest orogen-parallel extension was occurring as a result of transtension. This study reveals a transition from south-directed extrusion of the GHS to orogen-parallel extension between ~15–13 Ma. Comparing these data with tectonic events across the Himalaya reveals an orogen-wide middle Miocene transition, coeval with the uplift of eastern Tibet. This is consistent with interpretations invoking radial spreading of Tibet and east-directed lower-crustal flow to explain orogen-parallel extension. Our study leads to the suggestion that a transition affecting mid- to lower-crustal processes may be responsible for the cessation of south-directed extrusion of the GHS and onset of east-directed lower-crustal flow. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2012-09-23 02:16:09.326
45

The structure and metamorphic evolution of the High Himalayan Slab in SE Zanskar and NW Lahaul

Walker, James David January 1998 (has links)
This thesis attempts to unravel the complex thermal and structural history of part of the High Himalayan Slab in NW India and combines reconnaissance-style field structural mapping of an area covering ~10,000 km<sup>2</sup> with petrography, microstructural analysis, thermobarometry and geochronology techniques. The results of this work show that the oldest protoliths of the High Himalayan Slab are at least Cambrian in age and that they may have experienced a major pre-Himalayan metamorphism at c.500 Ma. The youngest protoliths are Mesozoic in age (the Tandi Group) and demonstrate that the High Himalayan Slab represents the metamorphosed equivalents of the Tibetan Sedimentary Series. Metamorphism was achieved via substantial crustal shortening and thickening following the India-Asia collision at 50-54 Ma ago. Phase relationships demonstrate that metamorphism was a regional Barrovian-type event associated with the growth of biotite-, garnet-, staurolite-, kyanite- and sillimanite-bearing assemblages in metapelites. Quantitative thermobarometry demonstrates that near-peak conditions of c.6-8 kbar and 550-650°C were attained in the deepest exposed levels. Growth of metamorphic assemblages was underway by at least 30 Ma, as indicated by U-Pb ages of metamorphic monazites. Exhumation of the High Himalayan Slab was achieved through a combination of extensional unroofing along major detachments (namely the Zanskar Shear Zone), thermal doming, thrusting along the Main Central Thrust and surface erosion. Exhumation is closely associated with the growth of sillimanite- and cordierite-bearing assemblages in pelites and the generation and emplacement of crustal melt leucogranites in the upper parts of the slab. U-Pb dating of accessory phases from one of the crustal melt leucogranites (the Gumburanjon leucogranite) constrains its crystallisation and emplacement age at c.21-22 Ma. This is only slightly older than its <sup>40</sup>Ar/<sup>39</sup>Ar muscovite and biotite cooling ages of c.20-21 Ma, which is attributed to the emplacement of the Gumburanjon leucogranite into the immediate footwall of the ZSZ. Field and geochronological data therefore support a strong temporal and spatial relationship between upper crustal melting and extension in a convergent orogen.
46

Textural and petrological studies of anatexis and melt transfer in the Himalayan Orogen

Dyck, Brendan January 2016 (has links)
Mineral textures, preserved in the metamorphosed sedimentary sequences that are exposed in orogenic hinterlands, are crucial to understanding the architecture and evolution of collisional mountain belts. In this thesis the textural record of anatexis and melt transfer in the Himalayan metamorphic core is decoded and the controls that these processes exert on the tectonic evolution of the Himalaya are explored. The problem is divided into two parts, corresponding to variations in protolith lithostratigraphy: melt source - the pelitic region where melt was first generated, and melt sink - the psammitic region where melt accumulated and crystallised. Dehydration melting of muscovite has long been recognized as a critical reaction for the generation of anatectic melt in the Himalaya, but a textural understanding of how this reaction progresses is limited by the inherent difficulties in identifying specific reaction products. Using samples collected from the Langtang area in central Nepal, a mechanistic model for muscovite dehydration melting was constructed, and a set of textural criteria were developed, which were used to distinguish peritectic K-feldspar from K-feldspar grains formed during melt crystallisation. Melt is transferred from the source to the sink in two stages: firstly along a pervasive network of mineral grain boundaries, and secondly via a channelised network of sills and dykes in the melt sink where it solidified as leucogranite. Variation in the primary mineral assemblage and appearance of leucogranite bodies reflect the degree of interaction that occurred between the melt and metasedimentary country rock, rather than a change in primary melt composition. The modal proportion of K-feldspar in the melt source requires vapour-absent conditions during muscovite dehydration melting and leucogranite formation, indicating that the generation of large volumes of granitic melts in orogenic belts is not necessarily contingent on an external source of fluids. The crystallisation of hydrous minerals in leucogranite consumes &LT;15.5 % of water released by the breakdown of muscovite. These results indicate that anatexis efficiently dehydrates the middle crust and suggests that the continents have limited potential to store water over geological time.
47

Exploring the history of India-Eurasia collision and subsequent deformation in the Indus Basin, NW Indian Himalaya

January 2011 (has links)
abstract: Understanding the evolution of the Himalayan-Tibetan orogen is important because of its purported effects on global geodynamics, geochemistry and climate. It is surprising that the timing of initiation of this canonical collisional orogen is poorly constrained, with estimates ranging from Late Cretaceous to Early Oligocene. This study focuses on the Ladakh region in the northwestern Indian Himalaya, where early workers suggested that sedimentary deposits of the Indus Basin molasse sequence, located in the suture zone, preserve a record of the early evolution of orogenesis, including initial collision between India and Eurasia. Recent studies have challenged this interpretation, but resolution of the issue has been hampered by poor accessibility, paucity of robust depositional age constraints, and disputed provenance of many units in the succession. To achieve a better understanding of the stratigraphy of the Indus Basin, multispectral remote sensing image analysis resulted in a new geologic map that is consistent with field observations and previously published datasets, but suggests a substantial revision and simplification of the commonly assumed stratigraphic architecture of the basin. This stratigraphic framework guided a series of new provenance studies, wherein detrital U-Pb geochronology, 40Ar/39Ar and (U-Th)/He thermochronology, and trace-element geochemistry not only discount the hypothesis that collision began in the Early Oligocene, but also demonstrate that both Indian and Eurasian detritus arrived in the basin prior to deposition of the last marine limestone, constraining the age of collision to older than Early Eocene. Detrital (U-Th)/He thermochronology further elucidates the thermal history of the basin. Thus, we constrain backthrusting, thought to be an important mechanism by which Miocene convergence was accommodated, to between 11-7 Ma. Finally, an unprecedented conventional (U-Th)/He thermochronologic dataset was generated from a modern river sand to assess steady state assumptions of the source region. Using these data, the question of the minimum number of dates required for robust interpretation was critically evaluated. The application of a newly developed (U-Th)/He UV-laser-microprobe thermochronologic technique confirmed the results of the conventional dataset. This technique improves the practical utility of detrital mineral (U-Th)/He thermochronology, and will facilitate future studies of this type. / Dissertation/Thesis / Ph.D. Geological Sciences 2011
48

Systematics of Clematis in Nepal, the evolution of tribe Anemoneae DC (Ranunculaceae) and phylogeography and the dynamics of speciation in the Himalaya

Elliott, Alan Cant January 2016 (has links)
The genus Clematis L. (Ranunculaceae) was used as a new model group to assess the role of the Himalayan orogeny on generation of biodiversity through investigations of its phylogeny, phylogeography and taxonomy. Although existing checklists include 28 species of Clematis from Nepal, a comprehensive taxonomic revision of available material in herbaria and additional sampling from fieldwork during this study has led to the recognition of 21 species of Clematis in Nepal, including one species (C. kilungensis) not previously recorded from Nepal. Exisiting phylogenetic and taxonomic concepts were tested with the addition of new samples from Nepal. The results highlight the shortcomings of the previous studies which were poorly resolved and indicate the need for a thorough revision of the sectional classification. Despite the increased sampling the results are still equivocal due to poor statistical support along the backbone of the phylogeny. Groups of species in well supported terminal clades are broadly comparable with results from previous studies although there are fewer clearly recognisable and well supported clades. The published dates for the evolution of Clematis were tested and the methodology of the previous study critically reappraised. The results indicate that the genus Clematis is approximately twice as old as previously reported and evolved in the middle Miocene. The phylogeny also demonstrates that, even allowing for poor support for the relationships between groups of species within Clematis, the extant Nepalese species must have multiple independent origins from at least 6 different colonisations. With their occurrence in the Pliocene and Pleistocene, these events are relatively recent in relation to the Himalayan orogeny, and may be linked more to the dispersal ability of Clematis than to the direct effects of the orogeny. Additional Nepalese samples of Koenigia and Meconopsis were added to exisiting datasets and these were reanalysed. The result from Clematis, Koenigia and Meconopsis were appraised in light of the the geocientific literature and previously published phylogeographic studies to create an overview of the drivers behind speciation in the Himalaya.
49

Tectonic and climatic influence on the evolution of the Bhutan Himalaya

January 2014 (has links)
abstract: The Himalaya are the archetypal example of a continental collision belt, formed by the ongoing convergence between India and Eurasia. Boasting some of the highest and most rugged topography on Earth, there is currently no consensus on how climatic and tectonic processes have combined to shape its topographic evolution. The Kingdom of Bhutan in the eastern Himalaya provides a unique opportunity to study the interconnections among Himalayan climate, topography, erosion, and tectonics. The eastern Himalaya are remarkably different from the rest of the orogen, most strikingly due to the presence of the Shillong Plateau to the south of the Himalayan rangefront. The tectonic structures associated with the Shillong Plateau have accommodated convergence between India and Eurasia and created a natural experiment to test the possible response of the Himalaya to a reduction in local shortening. In addition, the position and orientation of the plateau topography has intercepted moisture once bound for the Himalaya and created a natural experiment to test the possible response of the range to a reduction in rainfall. I focused this study around the gently rolling landscapes found in the middle of the otherwise extremely rugged Bhutan Himalaya, with the understanding that these landscapes likely record a recent change in the evolution of the range. I have used geochronometric, thermochronometric, and cosmogenic nuclide techniques, combined with thermal-kinematic and landscape evolution models to draw three primary conclusions. 1) The cooling histories of bedrock samples from the hinterland of the Bhutan Himalaya show a protracted decrease in erosion rate from the Middle Miocene toward the Pliocene. I have attributed this change to a reduction in shortening rates across the Himalayan mountain belt, due to increased accommodation of shortening across the Shillong Plateau. 2) The low-relief landscapes of Bhutan were likely created by backtilting and surface uplift produced by an active, blind, hinterland duplex. These landscapes were formed during surface uplift, which initiated ca. 1.5 Ma and has totaled 800 m. 3) Millennial-scale erosion rates are coupled with modern rainfall rates. Non-linear relationships between topographic metrics and erosion rates, suggest a fundamental difference in the mode of river incision within the drier interior of Bhutan and the wetter foothills. / Dissertation/Thesis / Ph.D. Geological Sciences 2014
50

Quantification of glacier melt volume in the Indus River watershed

Asay, Maria Nicole 07 December 2011 (has links) (PDF)
Quantifying the contribution of glaciers to water resources is particularly important in locations where glaciers may provide a large percentage of total river discharge. In some remote locations, direct field measurements of melt rates are difficult to acquire, so alternate approaches are needed. Positive degree-day modeling (PDD) of glacier melt is a valuable tool to making first order approximations of the volume of melt coming from glaciers. In this study, a PDD-melt model is applied to glaciers in the Indus River watershed located in Afghanistan, China, India, and Pakistan. Here, millions of people rely on the water from the Indus River, which previous work suggests may be heavily dependent on glacier melt from high mountain regions in the northern part of the watershed. In this region, the PDD melt model calculates the range of melt volumes from more than 45,000 km2 of glaciated area. It relies on a limited suite of input variables for glaciers in the region: elevation, temperature, temperature lapse rate, melt factor, and surface area. Three global gridded climate datasets were used to determine the bounds of temperature at each glacier: UEA CRU CL 2.0, UEA CRU TS 2.1, and NCEP/NCAR 40 year reanalysis. The PDD melt model was run using four different melt scenarios: mean, minimum, maximum, and randomized. These scenarios account for differences in melt volume not captured by temperature, and take uncertainties in all input parameters into account to bound the possible melt volume. The spread in total melt volume from the model scenarios ranges between 27 km3 and 439 km3. While the difference in these calculations is large, it is highly likely the real value falls within this range. Importantly, even the smallest model volume output is a significant melt water value. This suggests that even when forcing the absolute smallest volume of melt, the glacier contribution to the Indus watershed is significant. In addition to providing information about melt volume, this model helps to highlight glaciers with the greatest contribution to total melt. Despite differences in the individual climate models, the spatial pattern in glacier melt is similar, with glaciers contributing the majority of total melt volume occurring in similar geographic regions regardless of which temperature dataset is used. For regions where glacier areas are reasonably well-constrained, contributions from individual glaciers can be quantified. Importantly, less than 5% of glaciers contribute at least 70% of the total melt volume in the watershed. The majority of these glaciers are in Pakistan, the region with the largest percentage of known glaciers with large surface areas at lower elevations. In addition to calculating current melt volumes over large glaciated areas, this model can also be used to determine future melt rates under differing climate scenarios. By applying suggested future regional temperature change to the temperature data, the impact on average melt rate over the watershed was found to increase from 3.02 m/year to 4.69 m/year with up to 2 °C temperature increase. Assuming glacier area remains relatively constant over short time periods, this would amount to a 145 km3 increase in melt volume.

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