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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.
21

Anatexis and metamorphism of crustal rocks during magmatic accretion : field and numerical results /

Barboza, Scott A. January 1998 (has links)
Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [158]-174).
22

Basic magnesian rocks associated with the corundum deposits of Georgia ...

King, Francis Plaisted, January 1906 (has links)
Thesis (Ph. D.)--Johns Hopkins University, 1897. / Life.
23

Emplacement of the Irian ophiolite and unroofing of the Ruffaer metamorphic belt of Irian Jaya, Indonesia /

Weiland, Richard John, January 1999 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 489-525). Available also in a digital version from Dissertation Abstracts.
24

Contribution to the petrology of the metamorphic rocks of western Celebes

Egeler, Cornelis Geoffrey. January 1946 (has links)
Proefschrift--Amsterdam. / "Samenvatting": p. [ix]-xiii. "Stellingen": ([3] p.) inserted. "Literature": p. [164]-165.
25

Thermoluminescence in contact metamorphosed rock

Johnson, Noye M. January 1962 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1962. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 204-206).
26

An experimental investigation of the reaction glaucophane + 2 quartz = 2 albite + talc /

Corona, Juan Carlos. January 2005 (has links)
Thesis (M.A.)--State University of New York at Binghamton, Department of Geological Sciences, 2005. / Includes bibliographical references.
27

Low-grade regional metamorphism of Paleozoic rocks in the Midland Valley of Scotland

Evans, Lesley Jayne January 1988 (has links)
Low-grade burial metamorphism in the Midland Valley of Scotland, has been investigated with reference to the Silurian sediments and to the Carboniferous volcanics. In the Silurian sediments, facies definitive phyllosilicates are absent. Thin-section examination indicates that cementation was early and despite strong deformation, the lack of cleavage is related to the isotropic dispersal of domains during burial. Scanning electron microscopy and X-ray diffraction define clay mineral assemblages which characterize the transformation of montmorillonite to illite during burial. Illite crystallinity, bo and conodont alteration, show values consistent with this transformation and are indicative of diagenetic/anchizone conditions. Metamorphism is related to Siluro-Devonian syn-sedimentary burial. Despite tentative links between the Midland Valley and the Southern Uplands during the Llandovery, the relative simplicity of the burial metamorphic sequence in the former region suggests that the Silurian trough became palaeo-geographically distinct. The Carboniferous volcanics have undergone burial metamorphism in the zeolite facies, which occurred once the bulk of the lavas had been extruded, and following burial beneath the Central and Ayrshire Basins. Alteration was dominated by hydrothermal processes and has resulted in the production of early greenstones, later burial metamorphic zones and palaeo-geothermal plumes. Seven zones have been defined upon the distribution of amygdale minerals. Thin-section examination however divides the zeolite facies in the Midland Valley into an upper analcime and a lower laumontite zone. Mineralogical assemblages are conducive with metamorphism at a) Pfluid = 2-4 kb at 200 °C and b) Pfluid = 2 kb at 350-420 °C, for the zeolite zones and the palaeo-geothermal plumes respectively. These values are compatible with burial depth estimates, with homogenization temperatures in fluid inclusions and with calcite-water fractionation temperatures. Water/rock ratios indicate that metamorphism was related to the flow of seawater and meteoric water through the volcanic sequences. Evidence for episodic boiling in fluid inclusions indicates fluid convection occurred, and was related to fracturing associated with a change from a lithostatic to a hydrostatic pressure regime. Seismic pumping was related to fracturing and to renewed magmatic activity in shallow chambers beneath the Midland Valley.
28

Structural-metamorphic imprint on part of the Namaqua mobile belt in Southwest Africa

Blignault, H J 02 October 2023 (has links) (PDF)
The cross-section of the part of the Namaqua Mobile Belt investigated, comprises tectonic domains differing in structural and metamorphic character. The upper-crustal Richtersveld Province is separated from the lower-crustal central zone by a marginal zone across which there is a sharp increase in P and T. A continuous prograde metamorphic zonation is established which is bounded on the low-grade side by the 'hornblende in' reaction and includes with increasing grade 'muscovite+ chlorite out', andalusite/sillimanite inversion, minimum melt line, •·epidote out', 'K-felspar + sillimanite in' and a brown hornblende zone. The PT conditions inferred for the K-felspar + sillimanite zone is in the order of 6 kb and 740°c. This metamorphic zonation is defined by the metamorphic peak at any one point and is associated with the early structures. Subsequent deformations indicate a continuous retrogression. The early kinematic event includes at least two phases of coaxial and coplanar folding giving rise to the main planar fabric which is interpreted as a shear surface. It is concluded that the first kinematic event constitutes a thrust regime. The latE kinematic event is represented in the central zone by two phases of macroscopic folding which yielded basin and dome structures. To accommodate the resultant lateral shortening in the central zone, the Kanabeam shear zone developed between the central zone and the more upper-crustal domains where the late phase folding is not developed. Two discrete magmatic events, yielding differentiated intrusive are closely related in time to the early kinematic event. These intrusives underlie at least 50 per cent of the area. The Vioolsdrif Suite (1900 Ma) is genetically related to the Orange River volcanics. The intersected volcanics (2000 Ma) and intrusives form the Vioolsdrif igneous complex which is correlated with the grey gneiss of the lower-crustal domains. In the high-grade central zone aluminous paragneisses structurally overlie the grey gneisses and are interpreted as a mudstone/wacke sequence. The early kinematic event, associated with thrusting, the main metamorphism and extensive intrusion, constitutes the main phase of the Namaqua tectogenesis which connnenced at least at about 1900 Ma. The late kinematic event is associated with lateral movement and shortening during the waning stages of the Namaqua tectogenesis at about 1000 Ma.
29

An integrated petrofabric study of the high-pressure Orlica-Śnieźnik Complex, Czech Republic and Poland

Pressler, Rebecca E. January 2006 (has links)
Thesis (M.S.)--Ohio University, June, 2006. / Title from PDF t.p. Includes bibliographical references (p. 42-46)
30

Mechanisms of shear zone deformation

Attfield, Peter Richard January 1988 (has links)
No description available.

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