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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.
101

Étude de la genèse des pépérites et de leur contexte volcano-sédimentaire, formation de Blondeau, Chibougamau, Québec /

Lefebvre, Christian. January 1991 (has links)
Mémoire (M.Sc.T.)-- Université du Québec à Chicoutimi, 1991. / "Mémoire présenté en vue de l'obtention de la maîtrise en sciences de la terre" CaQCU Bibliogr.: f. 166-171. Document électronique également accessible en format PDF. CaQCU
102

The Quaternary geology and sequence stratigraphy of Lake Bonneville deposits in the Matlin quadrangle, Box Elder County, northwestern Utah /

Cavas, Matthew P. January 2003 (has links)
Thesis (M.S.)--Ohio University, November, 2003. / Includes bibliographical references (p. 73-77).
103

Petrology and geochemistry of volcanic rocks of the Lantau Peak Area, Lantau Island, Hong Kong /

So, Chak-tong, Anthony. January 1999 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 123-128).
104

Tracking the evolution of mid cenozoic silicic magma systems in the southern Chocolate Mountains region, California using zircon geochemistry and quartz and zircon geothermometry /

Needy, Sarah Katherine. January 2009 (has links)
Thesis (M.S.)--Indiana University, 2009. / Department of Earth Sciences, Indiana University-Purdue University Indianapolis (IUPUI). Advisor(s): Andrew P. Barth, Gabriel Filippelli, Jeffery Wilson. Includes vitae. Includes bibliographical references (leaves 62-64).
105

Geology of the middle and upper Eocene McIntosh Formation and adjacent volcanic and sedimentary rock units, Willapa Hills, Pacific County, southwest Washington /

Moothart, Steve Rene' January 1992 (has links)
Thesis (M.S.)--Oregon State University, 1993. / Includes mounted photographs. Three folded plates in pocket. Typescript (photocopy). Includes bibliographical references (leaves 213-225). Also available on the World Wide Web.
106

Die sedimentologische Entwicklung der Permabfolge im westlichen Südtirol (N-Italien)

Fels, Helmut, January 1900 (has links)
Thesis (doctoral)--Universität zu Köln, 1982. / Bibliography: p. 131-144.
107

Use of volatile and trace elements to infer geodynamic and magmatic processes : Ontong Java Plateau (Western Pacific) and Bishop Tuff (Eastern California) /

Roberge, Julie, January 2005 (has links)
Thesis (Ph. D.)--University of Oregon, 2005. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 143-153). Also available for download via the World Wide Web; free to University of Oregon users.
108

The Quaternary geology and sequence stratigraphy of Lake Bonneville deposits in the Matlin quadrangle, Box Elder County, northwestern Utah

Cavas, Matthew P. January 2003 (has links)
Thesis (M.S.)--Ohio University, November, 2003. / Title from PDF t.p. Includes bibliographical references (p. 73-77)
109

Tephrochronology as a tool for assessing the synchronicity of Middle Palaeolithic and Upper Palaeolithic techno-complexes in the Caucasus

Cullen, Victoria Louise January 2015 (has links)
The Caucasus is a land corridor between the Black and Caspian seas, linking Africa to Northern Eurasia, and is considered a migratory route for Neanderthals and Anatomically Modern Humans (AMH). Numerous cave sites in Armenia, Azerbaijan, Georgia and southwestern Russia indicate that Neanderthals and AMH occupied the region, but poor chronological control meant that the precise timing of the occupations was unknown. This work involved identifying and geochemically characterising volcanic ash layers (tephra) in archaeological cave and open air sites spanning approximately 125 ka to 30 ka to generate a tephrostratigraphic framework. This framework was used to correlate the sites and assess the synchronicity of Neanderthal and AMH occupation across the region. Tephra investigations were also carried out on a core (M72/5-25-GC1) from the southeast Black Sea (that spans the last ~ 60 ka), with the aim of linking the archaeological sites to this palaeoenvironmental archive, to investigate the impact changes in climate had on the archaeology in the region. Eleven of the archaeological sites investigated (Gubs rock shelter and Weasel Cave in Russia; Ortvale Klde, Ortvale Cave, Sakajia and Undo Cave in Georgia; Aghitue 3, Lusakert 1, Fantan and Kagasi in Armenia; and Azokh Cave in Azerbaijan) had tephra, 30 cryptotephras and 8 visible layers, preserved. Twenty-two tephra layers were identified in the Black Sea core, with distinct periods of frequent volcanic activity separated by long periods, up to 9 ka, of seemingly volcanic quiescence in the region. The glass chemistry of the tephra found in the archaeological sites and the core, determined using a wavelength-dispersive electron microprobe, was used to characterise and correlate the units between the sedimentary sequences. Although some widespread tephra from the major Mediterranean sources (3.6 ka Minoan eruption from Santorini, Greece and the ~39 ka Campanian Ignimbrite super eruption from Campi Flegrei, Italy) were identified in the Black Sea core, none of the archaeological sites contained Mediterranean tephra. Most of the tephra layers in the archaeological sites investigated and the Black Sea core are from sources in the Caucasus and Turkey. The limited information on the volcanic history and compositional data of these sources in the region does not allow most of the units to be correlated to particular eruptions or volcanoes. However, some of the cryptotephra units have been correlated to eruptions from Nemrut, Acigöl and Erciyes Dagi volcanoes in Turkey. Unfortunately, there are no tephra layers that are common to the Black Sea core and any of the archaeological sites, prohibiting direct correlation of the sites to this detailed palaeoenvironmental record. However, the ~30 ka Nemrut Formation (NF) eruption from Nemrut volcano, Turkey, is found in the Lake Van palaeoenvironmental record and in two of the archaeological sites. This allows the archaeological sites to be correlated to each other and palaeoclimate information can also be imported into these sites. More detailed characterisation of the proximal deposits may allow more units to be correlated to eruptions and will enable these distal records to be used to further constrain the tempo of explosive volcanic activity in the region. A few compositionally distinct tephra layers were found and a suite of new radiocarbon dates were obtained at various sites, allowing archaeological occupations to be dated and the synchronicity between sites to be assessed. A distinct rhyolitic tephra correlates a layer with an Upper Palaeolithic stone technology, associated with AMH, in Azokh Cave (Azerbaijan) to a layer in Sakajia cave (Georgia) that contains Neanderthal remains. This is clear evidence that AMH and Neanderthals were in the region (within 600 km) at the same time. Other sites have also been correlated with tephra. A dacitic tephra correlates a unit with an Upper Palaeolithic lithic and bone tool techno-complex in Ortvale Klde (Georgia) to a unit with a Middle Palaeolithic lithic assemblage in Lusakert 1 (Armenia). The Middle Paleolithic tool assemblage in Lusakert 1 is clearly different from the Upper Paleolithic assemblage that is clearly associated with AMH in Ortvale Klde, but it is not clear whether the other assemblage is associated with Neanderthals, archaic modern humans or AMH. This correlation between different lithic assemblages clearly indicates that there were different groups, with different technologies, occupying the region at the same time. The NF tephra is also found shallower in the sequences at both Lusakert 1 and Ortvale Klde. This time marker shows that the Middle Paleolithic assemblage is still being used in Lusakert 1 at ~30 ka, indicating that a less diverse stone techno-complex was used for a prolonged period of time in central Armenia. There does not appear to be any direct relationship between occupation in the region and the climate at the time, implying that this had little effect on the archaeological story in the region. A new radiocarbon based age model that combines new dates with published data for the sites within the Caucasus shows temporal overlap between AMH and Neanderthals in the region. This confirms the tephra correlations and clearly indicates both species co-existed in the Caucasus. The new radiocarbon data also suggest that AMH arrived in the region earlier than previously thought, at ~50-44 ka cal BP. The arrival of AMH in the Caucasus is now temporally similar to other early AMH sites in northern Eurasia.
110

A geohydrologic investigation of volcanic rocks using the gravity survey method: Galiuro Mountains, Graham, Pinal and Cochise Counties, Arizona

Schwartz, Kerry Lisa, 1962-, Schwartz, Kerry Lisa, 1962- January 1990 (has links)
No description available.

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