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dc.contributor.authorKarakas, Ozgeen_US
dc.date.accessioned2013-01-17T22:08:42Z
dc.date.available2013-01-17T22:08:42Z
dc.date.issued2011-11-16en_US
dc.identifier.urihttp://hdl.handle.net/1853/45964
dc.description.abstractWe develop a two dimensional model that simulates the response of the crust to prolonged mantle-derived intrusions in arc environments. The domain includes the entire crustal section and upper mantle and focuses on the evolving thermal structure due to intrusions and external tectonic forcing. We monitor the thermal response, melt fraction and volume for different environments after a definite time by considering geologically relevant melt flux and extensional tectonic rates. The amount of crustal melt versus fractionated primary mantle melts present in the crustal column helps determine crustal structure and growth through time. We observe that with a geophysically estimated flux and tectonic rate, the mantle-derived magma bodies can melt the surrounding volume of crust. We express the amount of crustal melting in terms of an efficiency; therefore we define the melting efficiency as the ratio of the melted volume of crustal material to the volume of melt expected from a strict enthalpy balance as explained by Dufek and Bergantz (2005). Melting efficiencies are less than 1.0 in real systems because heat diffuses to sections of the crust that never melt. The maximum calculated efficiency is 0.05 in our model while most of our simulations show zero efficiency. Additionally, maximum total melt amount is observed in relatively greater extensional environments (0.02 m/yr) and high intrusion rates (10⁻² m³/m²/yr) and in long time periods (2 x 10⁶ years). However, maximum crustal melting in the same environment is reached in 1.2 x 10⁶ years. The relative amounts of mantle-derived and crustal melts in the total volume of magma suggest that the majority of magma composition in crustal column is derived from the mantle material.en_US
dc.publisherGeorgia Institute of Technologyen_US
dc.subjectSubduction zonesen_US
dc.subject2D thermal modelen_US
dc.subjectExtensional tectonic environmentsen_US
dc.subjectStochastic dike intrusionsen_US
dc.subjectCrustal meltingen_US
dc.subjectEfficiency of crustal meltingen_US
dc.subject.lcshGeology, Structural
dc.subject.lcshGeology
dc.subject.lcshGeochemistry
dc.subject.lcshEarth (Planet) Crust
dc.titleModulation of crustal magmatic systems by external tectonic forcingen_US
dc.typeThesisen_US
dc.description.degreeMSen_US
dc.contributor.departmentEarth and Atmospheric Sciencesen_US
dc.description.advisorCommittee Chair: Dufek, Josef; Committee Member: Newman, Andrew; Committee Member: Peng, Zhigangen_US


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