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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

Magmatic accretion of the upper oceanic crust /

Naidoo, Devamonie Dayanithie. January 1998 (has links)
Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographic references (leaves [286]-319).
2

Mineralogy and geochemistry of Devonian minor intrusions and their xenoliths from the Kola Peninsula and the Arkhangelsk region, Russia

Beard, Andrew David January 2001 (has links)
No description available.
3

Petrogenesis of Late Cenozoic collision volcanism in Western Anatolia, Turkey

Aldanmaz, Ercan January 1998 (has links)
Western Anatolia exhibits a record of almost all stages of a collision event and its related magmatic processes. Following an Eocene continent-arc collision, Western Anatolia region experienced a complete cycle of thickening and orogenic collapse. The early stage of collision- related volcanism, which was most evident during the Early Miocene (<21 Ma), produced a considerable volume of lavas and pyroclastic deposits covering a broad compositional range from basaltic andesites to rhyolites. The volcanic activity continued into the Middle Miocene with a gradual change in eruptive style and rock compositions. The Middle Miocene activity, formed in relation to localised extensional basins and was dominated by lava flows and dykes of basalts to andesites composition. Both the Early-Middle Miocene rocks have calc-alkaline and shoshonitic character. The late stage volcanism, from 11.0 to 8.3 Ma, was marked by alkali basalts and basanites erupted along the localised extensional zones. The Early-Middle Miocene volcanic rocks exhibit enrichment in LILE and LREE relative to the HFSE (characterised by negative Nb and Ta anomalies) and are characterised by high (^87)Sr/(^86)Sr and low (^143)Nd/(^144)Nd (-ɛno) ratios. These characteristics indicate a mantle lithospheric source region carrying a subduction component inherited from a pre-collision subduction event. Perturbation of this subduction-metasomatised lithosphere by delamination of the thermal boundary layer is the likely mechanism for the initiation of the post-collision magmatism. Trace elements systematics suggest that the Early-Middle Miocene series underwent a hydrous crystallisation (dominated by pargasitic amphibole) in deep crustal magma chambers. Subsequent crystallisation in shallower magma chambers follows two different trends: (1) anhydrous (pyroxene + plagioclase-dominated; and (2) hydrous (edenitic amphibole + plagioclase + pyroxene dominated).Trace element and isotope modelling shows that the Early-Middle Miocene rocks have been affected by assimilation combined with fractional crystallisation processes, and that the effects of assimilation decrease gradually from the Early Miocene into the Middle Miocene. This indicates a progressive crustal thinning related to the extensional tectonics that prevailed from the latest Early Miocene onwards. In contrast to the Early-Middle Miocene rocks, the Late Miocene alkaline rocks are characterised by low (^87)Sr/(^86)Sr and high (^143)Nd/(^144)Nd (+ɛnd) ratios and have OIB-type like trace element patterns characterised by enrichment in LILE, HFSE and L-MREE, and a slight depletion in HREE, relative to the N-MORB compositions. REE inversion modelling indicates that these rocks formed by partial melting (with degrees of ~2 to -10%) of a spinel + garnet Iherzolite source. Trace element and isotopic systematics are consistent with decompression melting of an enriched mantle asthenospheric source.
4

The Petrogenetic significance of melt inclusion and phenocryst compositions in Phyric Basalts from the Kane Fracture Zone and vicinity, 23-̊28 ̊N Mid-Atlantic ridge /

Sullivan, George Edward. January 1989 (has links)
Thesis (Ph.D.)--University of Tulsa, 1989. / Erratum inserted; leaf [241]. Bibliography: leaves 144-154.
5

Development of continental magmatic systems : insights from amphibole chemistry of the Altiplano Puna Volcanic Complex, Central Andes /

Abot, Manggon. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 62-67). Also available on the World Wide Web.
6

The evolution of silicic magmatism in the post-caldera volcanism of the Phlegrean Fields, Italy /

Roach, Angela Louise. January 2005 (has links)
Thesis (Ph.D.)--Brown University, 2005. / Vita. Thesis advisor: Malcolm J. Rutherford. Includes bibliographical references (leaves 29-32, 82-84, 129-131). Also available online.
7

Magmatic and tectonic evolution of Southern Tibet and the Himalaya.

Williams, Helen Myfanwy. January 2000 (has links)
Thesis (Ph. D.)--Open University. BLDSC no. DXN039344.
8

Mesozoic magmatic activity in Hong Kong

Wong, Po-wan, Kenny. January 2006 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.
9

The relation between deformation, granite source type and crustal growth : Peru

Petford, Nicholas January 1990 (has links)
No description available.
10

A-type granites of the Permian Emeishan large igneous province (SW China) implications for the formation of the giant magmatic oxide deposits /

Shellnutt, John Gregory. January 2007 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2007. / Also available in print.

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