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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.
51

Seismic structural analysis of deformation in the southern Mexican Ridges

Pew, Elliott 20 October 2011 (has links)
The southernmost region of the Mexican Ridges extends from Bryant's gap near 22.5 N latitude to the Campeche Knolls near 19.0 N latitude. Analysis of 23,030 kilometers of sparker and CDP seismic data from six surveys reveals the existence of two separate areas of folding, Zones 4a and 4b. In the Zone 4a foldbelt symmetrical folds form a gentle salient which parallels the curved outline of Isla de Tuxpan. Structural relief often in excess of 500 meters is reflected by similar bathymetric relief. Fold wavelengths average 10-12 kilometers. A detachment or decollement is interpreted in a thick Upper Cretaceous to Lower Tertiary pelagic shale sequence by the existence of relatively undeformed reflectors below this interval. The 3 to 3.5 kilometer thick allochthonous sheet has experienced approximately 1% shortening and a maximum displacement of 1 to 2 kilometers. The Zone 4a foldbelt appears to be a massive gravity slide. Folded Plio-Pleistocene strata establish the youth of these folds. A large deep-rooted structure of questionable origin is observed on GLG 22. This structure, exhibiting roughly 1500 meters of bathymetric relief, acts as a foreland buttress against which the gliding allochthonous mass deforms. The tightly appressed thrust-faulted folds up dip from the buttress exhibit anomalously short wavelengths. While no folding is observed directly down dip from the buttress, folding is observed 30 to 50 kilometers basinward of this structure just a few kilometers to the south. The boundary separating Zones 4a and 4b is a linear feature oriented transversely to regional strike and may be a tear fault. Reflections at depth are not continuous across this feature. The Zone 4b foldbelt lies directly down dip from the Veracruz Basin. Structural relief commonly doubling that observed in Zone 4a is rarely expressed as bathymetric relief. Individual folds are asymmetric, having gently dipping landward flanks and either steeply dipping or growth-faulted seaward flanks. Fold cores appear to contain diapiric material. Fold growth due to gravity sliding began in the Middle Miocene. Subsequent loading by a thick Middle-Upper Miocene section gradually halted downslope movement and initiated flowage of plastic substrata from beneath loaded synclinal troughs into anticlinal cores. This deformation has continued to the present in some folds. / text
52

Determination of spatial dependence in fracture set characteristics by geostatistical methods

Miller, Stanley Mark January 1979 (has links)
No description available.
53

Metamorphic studies in the south-east Tauern window, Austria

Droop, Giles T. R. January 1979 (has links)
Detailed structural and mineralogical mapping was undertaken in an area of 130 square kilometres within the Pennine Zone of the south-east Tauern Window, the Eastern Alps. A coherent tectono-metamorphic history is established for this area. Three pre-Alpine metamorphic events are recognised. The Alpine history involves two discrete phases of intense penetrative deformation which occurred under conditions of rising temperature, a widespread phase of thermal crystallisation at 35-40 mybp representing the attainment of maximum temperatures, and a minor post-metamorphic phase of deformation. The regional tectonic significance of this sequence is discussed. The spatial variation in Alpine peak metamorphic conditions is examined in terms of the distribution of mineral zones and isograds in metapelites. Staurolite+biotite assemblages were developed at low structural levels, and chloritoid+biotite assemblages along a thin wedge-shaped zone. Barrovian and Stonehavian facies series are both represented. Oxygen isotope studies on whole-rocks and mineral separates suggest that widespread circulation of metamorphic fluids did not occur during Alpine metamorphism. Thermodynamic calculations indicate that metamorphic conditions during the Alpine thermal peak were 570ºC and 7 kb at the basement-cover interface. These results can be reconciled both with models in which tectonic burial alone was sufficient to cause Alpine metamorphism of the Pennine Zone and with models in which a transient high heat flow regime is invoked.
54

Granulite- to amphibolite-facies metamorphism and penetrative deformation in a disrupted ophiolite, Kangaroo Mountain area, Klamath Mountains, California a deep view into the basement of an accreted, oceanic island arc /

Garlick, Sarah R. January 2007 (has links)
Thesis (M.S.)--University of Wyoming, 2007. / Title from PDF title page (viewed on Oct. 22, 2008). Supplemental files include a color map in PDF. Includes bibliographical references (p. 66-73).
55

Crustal shortening and tectonic evolution of the Salt Range in Northwest Himalaya, Pakistan /

Qayyum, Mazhar. January 1991 (has links)
Thesis (M.S.)--Oregon State University, 1992. / Typescript (photocopy). Includes bibliographical references (leaves 109-124). Also available via the World Wide Web.
56

Étude des styles structuraux des terrains de la ceinture parautochtone adjacents au front de Grenville situe à l'est de Senneterre /

Ducharme, Éric, January 1994 (has links)
Mémoire (M.Sc.T.)-- Univeristé du Québec à Chicoutimi, 1994. / Résumé disponible sur Internet. CaQCU Document électronique également accessible en format PDF. CaQCU
57

Interprétation des données de flux de chaleur et de gravité dans le Bouclier Canadien /

Cheng, Li Zhen, January 1999 (has links)
Thèse (D.R.M.)--Université du Québec à Montréal, 1999. / Bibliogr.: f. 176-197. Document électronique également accessible en format PDF. CaQCU
58

The genetic association between brittle deformation and quartz cementation examples from burial compaction and cataclasis /

Makowitz, Astrid. McBride, Earle F. Milliken, K. L. January 2004 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisors: Earle F. McBride and Kitty L. Milliken. Vita. Includes bibliographical references. Also available from UMI.
59

The genetic association between brittle deformation and quartz cementation : examples from burial compaction and cataclasis /

Makowitz, Astrid. January 2004 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2004. / Includes bibliographical references (p. 278-297). Available also in an electronic version.
60

The evolution of lithospheric deformation and crustal structure from continental margins to oceanic spreading centers /

Behn, Mark Dietrich, January 1900 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2002. / "Joint Program in Oceanography/Applied Ocean Science and Engineering."--Cover. "June 2002." Funding was provided by NASA through grants NAG5-3264, NAG5-4806, NAG5-11113 and NAG5-9143 and by a National Defense Science and Engineering Graduate Fellowship. Includes bibliographical references (p. 221-243).

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