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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.
1

Longitudinal distribution of radiolarians within Tethys

Marquez, Edanjarlo Joson. January 2003 (has links)
published_or_final_version / Earth Sciences / Doctoral / Doctor of Philosophy
2

Exhumation of Blueschist-facies assemblages from western Turkey : the significance of '4'0Ar-'3'9Ar ages and excess argon in a HPLT terrain

Sherlock, Sarah Christine January 1998 (has links)
No description available.
3

Sedimentary response to the tectonic uplift of the Kyrenia Range, northern Cyprus, in its Eastern Mediterranean tectonic setting

Palamakumbura, Romesh Niranjan January 2016 (has links)
The Kyrenia Range forms part of an approximately east-west lineament extending from northern Cyprus to southern Turkey. During Plio-Pleistocene the northern Cyprus segment of the lineament uplifted to ca. 1000 m above modern sea level. Plio- Pleistocene sediments document the uplift of the Kyrenia Range. A combination of sedimentology and a range of dating techniques including uranium series, optical stimulated luminescence (OSL), strontium isotopes and magnetostratigraphy are used to help understand the geological processes controlling uplift. Shallowing from a deepmarine basin to a shallow-marine, cool-water carbonate ramp represents the earliest uplift of the Kyrenia Range. The base of the carbonate ramp is made up of thick-bedded, benthic foraminiferal-rich grainstones, which are discontinuously overlain by calcareous red algal-rich rudstones. Erosively overlying this sequence is a coral- and molluscrich conglomerate, representing a short-lived relative sea-level fall. The upper part of the carbonate ramp sequence is composed of cross-bedded grainstone representing a shoreface environment. Interbedded with the upper grainstone facies are occasional fluvial conglomerates. The shallowing-upward marine environment represents the earliest emergence of the Kyrenia Range. After a major break in deposition, six marine and non-marine terraces (K0 to K5) reflect the sedimentary response to the main phase of tectonic uplift of the Kyrenia Range. The K0 terrace, the oldest and highest terrace, is composed of megabreccia and is interpreted as representing a major phase of rapid tectonic uplift. The K2-K5 terraces form a series marine to non-marine terraces on the northern flank of the range and also non-marine terraces on the southern flank of the range. The terraces on the northern flank each begin with a major marine transgression followed by a regressive sedimentary sequence. Marine environments range from nearshore open-marine below the storm-wave base, to shoreface, foreshore (beachrock), and backshore lagoonal environments. The non-marine environments range from aeolian dune to fluvial drainage systems. The fluvial systems are characterised by channelised debris-flow deposits interbedded with mudstones and palaeosols. The non-marine deposits on the southern flank of the range comprise a series of fluvial drainage systems. The fluvial systems on the southern flank of the range comprise a mixture of planar-bedded and channelised conglomerates, mudstones and aeolianites. Portable luminescence data are used to correlate quantitatively the K4 and K5 terraces on both the northern and southern flanks of the range. Each of the K4 and K5 terraces produce a unique luminescence signal, which is used as the basis for correlating the lower terraces. The unique luminescence signals of the K4 and K5 terraces are likely to be caused by varying sedimentary histories of the quartz and feldspar grains within the two terraces. The shallow-marine environments surrounding the Kyrenia Range prior to major uplift were dated using strontium isotopes and palaeomagnetism. The results of this dating suggest that marine environments persisted throughout the Early Pleistocene. U-series and OSL dating were used to date the K4 and K5 terraces on the northern flank of the range. The U-series results indicate that the marine deposits of the K4 terrace formed during several Middle Pleistocene interglacial stages. The OSL dating shows that the aeolian dunes of the K5 terrace formed during a Late Pleistocene glacial stage. The formation of the K2-K5 terraces was controlled by the interaction between tectonic uplift, climatic change and global eustatic sea-level change. The basal marine deposit of each terrace formed during an interglacial stage. Major fluvial deposition also occurs during the interglacial period as a result of a wetter climate. The inter-glacialglacial transition resulted in major fluvial erosion as a result of falling global sea-level. Aeolian carbonate deposition was dominant during the glacial stage, which represent arid climatic conditions. The only exception to this is the K4 terrace, which represents three glacial stages. The K1-K3 terraces can be correlated with the global sea-level curve suggesting approximate ages for each terrace, and ca. 600 ka for the entire K1- K5 terrace sequence. The Kyrenia Range underwent rapid uplift during the late Early Pleistocene at >1.2 mm/yr, followed by continuous but slower uplift during the Middle to Late Pleistocene. These results indicate that the uplift occurred in tandem with the Troodos Massif in southern Cyprus. The driving mechanism of the uplift of the Kyrenia Range is likely to be related to the collision of the Eratosthenes Seamount with the Cyprus trench to the south of the island. The seamount-trench collision resulted in compressional tectonics around Cyprus within the large-scale tectonic setting resulting from the early stages of convergence of the African and Eurasian plates.
4

Advancing the Implementation of Hydrologic Models as Web-Based Applications

Dahal, Prasanna 01 May 2018 (has links)
Deeper understanding of relationships between flow in river sand various hydrologic elements such as rainfall, land use, and soil type is imperative to solve water related problems like droughts and floods. Advanced computer models are becoming essential in helping us understand such relationships. However, preparing such models requires huge investment of time and resources, much of which are concentrated on acquisition and curation of data. This work introduces agree and open source web Application (web App) that provides researchers with simplified access to hydrological data and modeling functionality. The web App helps in the creation of both hydrologic models, and climatic and geographic data. Free and open source platforms such as Tethys and Hydro Share were used in the development of the web Apia physics based model called TOPographic Kinematic APproximation and Integration (TOPKAPI) was used as the driving use case for which a complete hydrologic modeling service was developed to demonstrate the approach. The final product is a complete modeling system accessible through the web to create hydrologic data and run a hydrologic model for a watershed of interest. An additional model, TOPNET, was incorporated to demonstrate the generality of the approach and capability for adding other models into the framework.
5

Lowering the Technological Barrier in Developing, Sharing and Installing Web GIS Applications

Khattar, Rohit Kumar 22 June 2022 (has links)
Portability of web applications between web servers of different organizations can be challenging and can complicate sharing and collaborative use of such tools. Given the distributed nature of the web, this lack of portability is usually not a concern because a user in one organization can link to and use a web application hosted by another organization. However, access control or differentiation may be needed by an organization in terms of area of interest, input data, analytical techniques, access control, presentation, branding, and language. This is true for many government organizations, and their associated web sites, and servers. In such cases, there are compelling political, branding, security, and privacy motivations that require each organization or agency to host and manage web applications on their own servers rather than using third party web sites over which they have little or no control. Also, web applications are classically developed by setting up a local software development and testing environment which can be challenging for new developers, be restricted by the software and hardware availability, cost significantly to obtain software development licenses and compatible hardware and is prone to code and data loss due to hardware damage or software corruptions. To simplify the discovery, deployment of web-based applications, I present the design, development, and testing of a system for discovering, installing, and configuring environmental analysis web applications on localized web servers. The system works with applications developed using Tethys Platform, which is an open-source software stack for creating geospatially enabled web-based applications. The developed Tethys App Store includes a Tethys application user interface that allows a server manager to retrieve applications from the central repository and install them on a local server with relatively simplicity, similar to the installation of a mobile application to a mobile device from a mobile application store. Next, I present the design concept of a cloud-based web application development platform, Tethys App Nursery, that attempts to overcome the above hurdles associated with localized development environments. A prototype of this system is developed and presented which is tightly integrated with Tethys platform and various cloud technologies provided by Amazon Web Services. The developed app nursery allows users to register for new Tethys portal instances in the cloud, develop new applications and test existing applications, without installing any local dependencies or development tools. Various cloud components used in this service's development as well as their associated costs are described. These systems were developed to support development of water and environmental analysis web apps for the international Group on Earth Observations (GEO) Global Water Sustainability (GEOGloWS) initiative of the National Aeronautics and Space Administration (NASA) and several partner organizations.
6

Variation of minerals and clay minerals recorded in the Neo-Tethys (central Turkey): new evidence of climatic changes during the middle Eocene / Variação no aporte de minerais e argilominerais registrados no Neo-Tethys (Turquia central): novas evidências de mudanças climáticas durante o Eoceno médio

Eric Siciliano Rêgo 27 July 2017 (has links)
Minerals and clay minerals in continental sedimentary successions are valuable tools for reconstructing past environmental conditions. Given the state of preservation of clays minerals, it is possible to identify how they were formed, providing clues about continental weathering conditions (inherited minerals) and geochemical conditions in the water column (neoformed or transformed). This study presents new mineralogical data from the Baskil section, a highly preserved middle Eocene succession in the Neo-Tethys (central Turkey). A gradual shift from a well-crystalline illite and chlorite interval (subsection I) to a detrital smectite dominant interval (subsection II) characterizes a change in source area from metamorphic to igneous rocks and changes from physical to chemical weathering conditions on land. This period coincides with the Middle Eocene Climatic Optimum (MECO), indicating a mineralogical signature of the event. Higher content of terrigenous input being deposited from 40.5 to 40 Ma caused a dilution effect of the carbonate materials as calcite and dolomite significantly decreases. Authigenic palygorskite showed an increasing trend from the middle to the uppermost portion of the section, indicating favorable conditions in the water column for its formation. We assume that conditions in the ocean circulation changed after 40 Ma, forming a stratified water column with warmer and saline conditions at greater depths, favoring palygorskite and possibly authigenic dolomite precipitation. The mineralogical evolution of the Baskil section reflects how sources and weathering regimes changed through time, and how these changes can be related to global (i.e. MECO) and/or local to regional processes. / Minerais e argilominerais em sucessões sedimentares são excelente ferramentas para a reconstrução de condições ambientais. Dado o estado de preservação dos argilominerais, é possível identificar como eles foram formados, fornecendo informação sobre as condições de intemperismo no continente e sobre condições geoquímicas na coluna d\'água. Este estudo apresenta novos dados mineralógicos da seção de Baskil, uma sucessão do Eoceno médio altamente preservada no Neo-Tethys (Turquia central). Uma mudança na assembléia mineralógica com maiores concentrações de ilita e clorita (subseção I) para um intervalo dominante de esmectita detrítica (subseção II) caracteriza uma mudança na área de fonte de rochas metamórficas para rochas ígneas e mudanças de condições de intemperismo físico para intemperismo químico. Este período coincide com o Ótimo Climático do Eoceno Médio (MECO), indicando uma assinatura mineralógica do evento. A paligorsquita autigênica teve um aumento na porção media e superior da seção, indicando condições favoráveis na coluna de água para a sua formação. Possívelmente as condições na circulação do oceano naquela região mudaram após 40 Ma, formando uma coluna de água estratificada com condições mais quentes e salinas em profundidades maiores, favorecendo precipitação de paligorsquita e dolomita. A evolução mineralógica da seção de Baskil reflete como as fontes e os regimes de intemperismo mudaram ao longo do tempo, e como essas mudanças podem estar relacionadas aos processos globais (e.g. MECO) e /ou a processos locais e regionais.
7

Variation of minerals and clay minerals recorded in the Neo-Tethys (central Turkey): new evidence of climatic changes during the middle Eocene / Variação no aporte de minerais e argilominerais registrados no Neo-Tethys (Turquia central): novas evidências de mudanças climáticas durante o Eoceno médio

Rêgo, Eric Siciliano 27 July 2017 (has links)
Minerals and clay minerals in continental sedimentary successions are valuable tools for reconstructing past environmental conditions. Given the state of preservation of clays minerals, it is possible to identify how they were formed, providing clues about continental weathering conditions (inherited minerals) and geochemical conditions in the water column (neoformed or transformed). This study presents new mineralogical data from the Baskil section, a highly preserved middle Eocene succession in the Neo-Tethys (central Turkey). A gradual shift from a well-crystalline illite and chlorite interval (subsection I) to a detrital smectite dominant interval (subsection II) characterizes a change in source area from metamorphic to igneous rocks and changes from physical to chemical weathering conditions on land. This period coincides with the Middle Eocene Climatic Optimum (MECO), indicating a mineralogical signature of the event. Higher content of terrigenous input being deposited from 40.5 to 40 Ma caused a dilution effect of the carbonate materials as calcite and dolomite significantly decreases. Authigenic palygorskite showed an increasing trend from the middle to the uppermost portion of the section, indicating favorable conditions in the water column for its formation. We assume that conditions in the ocean circulation changed after 40 Ma, forming a stratified water column with warmer and saline conditions at greater depths, favoring palygorskite and possibly authigenic dolomite precipitation. The mineralogical evolution of the Baskil section reflects how sources and weathering regimes changed through time, and how these changes can be related to global (i.e. MECO) and/or local to regional processes. / Minerais e argilominerais em sucessões sedimentares são excelente ferramentas para a reconstrução de condições ambientais. Dado o estado de preservação dos argilominerais, é possível identificar como eles foram formados, fornecendo informação sobre as condições de intemperismo no continente e sobre condições geoquímicas na coluna d\'água. Este estudo apresenta novos dados mineralógicos da seção de Baskil, uma sucessão do Eoceno médio altamente preservada no Neo-Tethys (Turquia central). Uma mudança na assembléia mineralógica com maiores concentrações de ilita e clorita (subseção I) para um intervalo dominante de esmectita detrítica (subseção II) caracteriza uma mudança na área de fonte de rochas metamórficas para rochas ígneas e mudanças de condições de intemperismo físico para intemperismo químico. Este período coincide com o Ótimo Climático do Eoceno Médio (MECO), indicando uma assinatura mineralógica do evento. A paligorsquita autigênica teve um aumento na porção media e superior da seção, indicando condições favoráveis na coluna de água para a sua formação. Possívelmente as condições na circulação do oceano naquela região mudaram após 40 Ma, formando uma coluna de água estratificada com condições mais quentes e salinas em profundidades maiores, favorecendo precipitação de paligorsquita e dolomita. A evolução mineralógica da seção de Baskil reflete como as fontes e os regimes de intemperismo mudaram ao longo do tempo, e como essas mudanças podem estar relacionadas aos processos globais (e.g. MECO) e /ou a processos locais e regionais.
8

Geochemistry, structure, and tectonic evolution of the Eldivan ophiolite, Ankara Melange, central Turkey/

Dangerfield, Anne, January 2008 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Geological Sciences, 2008. / Includes bibliographical references (p. 39-44).
9

Introducing the Water Data Explorer Web Application and Python Library: Uniform Means for Data Discovery and Access from CUAHSI and the WMO WHOS Systems

Romero Bustamante, Elkin Giovanni 03 April 2021 (has links)
There has been a growing recognition in recent years of the need for a standardized means for sharing water data on the web. One response to this need was the development of the Consortium of Universities for the Advancement of Hydrologic Science (CUAHSI) Hydrologic Information System (HIS) and its accompanying WaterOneFlow and WaterML protocols. To date, the primary means for accessing data shared using these protocols has been limited to the Microsoft Windows HydroDesktop software, the WaterML R package, and the web based CUAHSI HydroClient which serves as an access point to the CUAHSI HIS database. We recognized the need for a new web-based tool for accessing data from any system that supports WaterOneFlow web services and WaterML and that could be regionally customizable, giving access to the most locally relevant portions of the HIS database, and providing a means for international government agencies, research teams, and others to make use of the accompanying protocols on a locally managed web application. To fill this need, we developed the open source, lightweight, installable web application, Water Data Explorer (WDE) which supports any WaterOneFlow service and can be customized for different regions containing WaterOneFlow web services. The WDE supports data discovery, data visualization, and data download for the selected WaterOneFlow services. The WDE's structure consist of WaterOneFlow catalogs, servers, and individual measurement stations. The WDE provides a different User Interface for administrators and regular users. A server administrator can specify which datasets an individual instance of the WDE supports so that end users of the application can access data from the specified datasets. We modularized the core WaterOneFlow access code into a new open-source Python package called "Pywaterml" which provides the methods used by WDE to discover, visualize, and download data. This thesis presents the design and development of the WDE and the associated Pywaterml package, which was done in partnership with end-users from the WMO and was done in an iterative design-build process. We present two case studies which involve data discovery and visualization from the CUAHSI HIS and WMO Hydrological Observing System (WHOS). Both case studies demonstrate the regional customization of the WDE which allows creation of different custom versions of the same application to meet specific end-user needs. The WDE data discovery in both case studies focuses on discovering the different sites contained in a WaterOneFlow web service, and ontology-based data discovery for the different concept variables in each web service. The data visualization we present, focuses on the time series observation for the different sites in each system. Finally, we tested data downloading in data discovery and visualization by downloading the information of each site to the WDE database and allowing the user to download the time series data.
10

Geochemistry, structure, and tectonic evolution of the Eldivan ophiolite, Ankara Melange, central Turkey

Dangerfield, Anne 17 June 2008 (has links) (PDF)
The Eldivan ophiolite, in the Ankara Mélange, represents the remnant of an ocean basin that developed in the İzmir-Ankara-Erzincan Ocean and collapsed the form the İzmir -Ankara-Erzincan suture zone (İAESZ) through continental block collision. Whole-rock and mineral geochemical evidence show supra-subduction zone tectonomagmatic affinity for the ophiolite, revealing this basin formed in the upper plate of an intra-oceanic subduction zone. Detrital zircon from the ophiolitic mélange sandstone and the overlying Karadağ Formation suggest the ophiolites maximum age is 143.2 (±2) Ma, and the overlying Karadağ Formation is 105.2 (±5) Ma. The angular unconformity between the ophiolite and Karadağ formation reveal that the Eldivan ophiolite was imbricated between 105.2 (±5) Ma and 143.2 (±2) Ma. Petrographic analysis of sandstone from the ophiolitic mélange reveals a source terrain of a volcanic arc rather than a continental source. Structural restoration of the sheeted dike complex reveals the back or intra-arc spreading ridge of the Eldivan ophiolite as NE-SW, oblique to the Sakarya-Pontide continental margin. Three phases of evolution for the Eldivan ophiolite are constrained by complied age data: a constructional, destructional, and suturing phase. The evolution is similar the Philippine Sea Plate and Mariana Trough and fits well within the framework of other eastern Mediterranean Tethyan ophiolites.

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