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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.
71

Stratigraphie und Tektonik bei Fridingen und Mühlheim im Donautal

Bubeck, Wolfgang. January 1933 (has links)
Thesis (Doctoral)--Eberhard-Karls-Universität zu Tübingen, 1933. / Includes bibliographical references (p. 51-53).
72

Structure, stratigraphy, and tectonics preserved of the northwestern Bays Mountain synclinorium, Greene and Hawkins Counties, northeast Tennessee

Bultman, John Garrett, January 2005 (has links) (PDF)
Thesis (M.S.) -- University of Tennessee, Knoxville, 2005. / Title from title page screen (viewed on Feb. 1, 2006). Thesis advisor: Robert D. Hatcher, Jr. Vita. Includes bibliographical references.
73

The Middle Ordovician Tellico-Sevier syncline a stratigraphic, structural, and paleoseismic investigation /

Whisner, Stephen Christopher. January 2005 (has links) (PDF)
Thesis (Ph. D.) -- University of Tennessee, Knoxville, 2005. / Title from title page screen (viewed on Sep. 8, 2005). Thesis advisor: Robert D. Hatcher, Jr. Document formatted into pages (xvi, 230 p., [4] p. of plates : ill. (chiefly col.), maps). Vita. Includes bibliographical references (p. 159-173).
74

Structural and thermal evolution of the Gulf Extensional Province in Baja California, Mexico : implications for Neogene rifting and opening of the Gulf of California /

Seiler, Christina. January 2009 (has links)
Thesis (Ph.D.)--University of Melbourne, School of Earth Sciences, 2009. / Typescript. Includes bibliographical references.
75

Structural analysis of the hinge region of the Islay Anticline.

Rydeblad, Elin January 2016 (has links)
The hinge region of a major anticlinal fold structure in the SW Scottish Highlands was located in the eastern part of the Isle of Islay. The structure plunges gently NNW, with the hinge line measuring 02/026. The hinge region was located by mapping a 2km2 area comprised of deformed Neoproterozoic metasedimentary and metacarbonate rocks, and plotting the measurements on stereograms. The data collected was also analysed to attempt to asses evidence of refolding, and it is suggested in this thesis that the area displays evidence of at least one subsequent refolding event.
76

Structural Evolution of the Virgin Spring Phase of the Amargosa Chaos, Death Valley, California, USA

Castonguay, Samuel 10 October 2013 (has links)
The Amargosa Chaos and Fault of Death Valley are complex features that play important roles in various tectonic models. Some recent models claim the fault is a regional detachment accommodating 80 km of NW-directed transport that produced the Chaos in its hangingwall. I offer an alternative interpretation: the chaos is a product of multiphase deformation that likely spanned the late Mesozoic and Cenozoic. The Amargosa Fault represents just one of six deformation events. The accompanying map (supplemental file) shows the cross-cutting relationships among fault populations: (D1) 25% north-northwest directed shortening across an imbricate thrust and tight fold system; (D2) E-SE extension on five normal faults; (D3) extension-related folding, which folded the D2 faults; (D4) normal-oblique slip on the Amargosa Fault; (D5) E-W extension on domino faults; (D6) extension on the Black Mountains Frontal Fault. The D2 faults, not the Amargosa, created the enigmatic attenuation observed in the Chaos.
77

Evolução cenozóica da região de Jundiaí (SP)

Neves, Mirna Aparecida [UNESP] 18 June 1999 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:15Z (GMT). No. of bitstreams: 0 Previous issue date: 1999-06-18Bitstream added on 2014-06-13T19:13:17Z : No. of bitstreams: 1 neves_ma_me_rcla.pdf: 8679642 bytes, checksum: 5c01ef629bc53f21298ec0cf2a7dc4a5 (MD5) / Neste trabalho é apresentado um estudo das relações existentes entre a ocorrência de depósitos sedimentares nos arredores de Jundiaí (SP) e o papel das falhas e fraturas na sua formação, deformação e preservação, objetivando a investigação de alguns eventos sucedidos na evolução cenozóica da região. Os métodos utilizados envolvem a extração de informações de bases cartográfkas, de fotografias aéreas e imagem de satélite; a obtenção de informações litoestratigrâficas para interpretações paleoambientais e a coleta de dados estruturais para o estudo do controle estrutural sobre os depósitos sedimentares, sobre a morfologia do terreno e para o cálculo de tensores. O embasamento pré-cambriano é composto basicamente por gnaisses com grau variável de migmatização e intercalações de quartzitos, xistos, anfibolitos, gonditos e metaultrabasitos incluídos no Complexo Amparo ou Itapira e, de forma mais restrita, filitos pertencentes ao Grupo São Roque. Intrusões granitóides são bastante comuns na regiao, predominando, na área, o Complexo Grauitóide Itu. Recobrindo o embasamento, aparecem depósitos paleozóicos correlacionados com o Grupo ttarai-é, constituídos por diamictitos, folhelhos, ritmitos, argilitos e siltitos. Estas rochas fonnam corpos isolados, embutidos no embasamento cristalino por falhas normais. Depósitos terciários, compostos por diamictitos, conglomerados, arenitos e argilitos também ocorrem sob a forma de corpos isolados, preservados pela presença de niveis conglomeráticos basais, mais resistentes à erosão, ou devido a falhamentos que ocasionaram abatimento e basculamento de blocos. São definidas nove fácies sedimentares formando associações que sugerem a existência de um antigo sistema de leques aluviais, sob clima semi-árido, cem área fonte na Sena do Japi...
78

Estrutura, geocronologia e alojamento dos batólitos de Quixadá, Quixeramobim e Senandor Pompeu - Ceará central /

Nogueira, Johnson Fernandes. January 2004 (has links)
Orientador: Norberto Morales / Banca: Antonio Misson Godoy / Banca: Hans Dirk Ebert / Banca: Ticiano José Saraiva dos Santos / Banca: José de Araújo Nogueira Neto / Resumo: O Ceará Central caracteriza-se pela ocorrência de uma rede de zonas de cisalhamento preferencialmente orientada na direção NE-SW e/ou NNE-SSW. Associados espacialmente a estas zonas de cisalhamento ocorrem rochas intrusivas de dimensões variadas. Entre estas ocorrem os Batólitos de Quixeramobim, Quixadá e Senador Pompeu. Estes batólitos apresentam-se com forma alongada na direção NE-SW, subparalela às zonas de cisalharnento principais (Zonas de Cisalhamento de Senador Pompeu e Quixeramobim, por exemplo). O Batólito de Quixeramobim apresenta rochas agrupadas em seis diferentes fácies. As rochas desde batálito constituem uma série cálcio-alcatina granodiorítica, com dioritos predominantes e granitos 3A e quartzo-dioritos subordinados, ocupando a quase totalidade da área de ocorrência. O Batólito de Quixadá é composto por monzonitos e qz-monzonitos e o Batálito de Senador Pompeu por granodioritos e monzogranitos As características deformacionais, levantadas através de estudos das feições planares e lineares impressas nestas rochas, são sugestivas de um desenvolvimento progressivo em condições de estado magmático passando ao estado sálido, o que caracteriza as zonas de cisahamento principais como mobilizadoras de magmas e responsáveis pelo alojamento final das rochas. Datações radiométricas U-Pb e Pb-Pb forneceram idades de cristalização (alojamento) de 585 l 4,7 Ma (Quixadá), 587 l 14 Ma (Quixeramobim) e 561 l 15 Ma (Senador Pompeu). O mecanismo de alojamento sugerido para o Batólito de Quixadá compreende expulsão de magma de porções mais profundas para o local de alojamento final em regime transpressivo. Para os Batólitos de Senador Pompeu e Quixeramobim, sugere-se geração de espaço por nucleação de fraturas em extensão associada a transcorrência. Este último registrando variação de regime transtrativo para transpressivo. / Abstract: The Central Ceará (NE Brazil) has, as typical characteristic, a shear zone system network with directions in NE-SW and for NNE-SSW. In association with these shear zones occur intrusive rocks like Quixeramobim, Quixadá and Senador Pompeu Batholiths. They have elongated shape in NE-SW direction, broadly parallel to major dextral ductile shear zones. The Quixeramobim Batholith has rocks grouped in six different facies, characterizing a calc-alkaline series with diorites as major rock types. Subordinated granite and quartzdiorites also occur. The Quixadá Batholith is formed by monzonite e and quartzmonzonite. The Senador Pompeu Batholith includes granodiorites and monzogranites. These rocks have foliaton and lineation organization pattern that are suggestive of progressive fabric development in magmatic and solid state. The orientation of these features is broadly parallel to the shear zones that promote emplacement of lhe plutons. U-Pb and Pb-Pb minimum emplacement ages are 585 l 4.7 Ma (Quixadá), 587 l 14 Ma (Quixeramobim) e 561 l 15 Ma (Senador Pompeu). The emplacement of the Quixadá Batholith mechanism suggested is the squeeze of magma from deeper places into lhe crust to the final emplacement site in trasnpression. For the Quixeramobim and Senador Pompeu Batholiths, we suggest an emplacement mechanism with space generation by fracture nucleation in extension, into the transcurente framework. / Doutor
79

Structure, stratigraphy and sedimentology of the paleoproterozoic Nsuta manganese deposit, Ghana

Van Bart, Adrian 18 July 2008 (has links)
The Nsuta manganese deposit is located in the Western Region of Ghana, approximately five kilometers south of Tarkwa Goldfields. The deposit has been an important source of manganese ore since mining began in 1916. The purpose of this project was to produce a concise model of the stratigraphy, sedimentology and structural evolution of the deposit in support of future exploration projects. The manganese ores occur as an up to 45m thick carbonate bed in a thick turbidite-greenstone succession that is part of the ~2.2 Ga Birimian Supergroup. Calc-alkaline volcanics, volcaniclastics, turbidites, argillites and phyllites are thought to have been deposited in a backarc basin environment. The entire sedimentary succession, including the manganese orebody, is a thick turbidite package hosted between an upper and lower greenstone unit consisting predominantly of volcaniclastic material. The entire lithological succession at Nsuta is interpreted to have been deposited within the middle to lower reaches of a submarine fan environment. Field evidence suggests a simple stratigraphy, commencing with a lower greenstone unit composed largely of volcaniclastic material. This is followed by an upward-fining lower turbidite unit deposited in response to a marked transgression and sea level rise. Maximum rate of sea level rise provided ideal conditions for manganese precipitation and concentration, as detrital influx ceased. The central portion of the carbonate orebody that formed hosts the manganese orebody. An upward-coarsening turbidite unit follows above the carbonate unit. This upward-coarsening succession reflects a regression and a highstand systems tract in terms of sequence stratigraphic principles. It is capped by an unconformity that formed during a period of rapid relative sea level fall. It is overlain by a second upward-fining turbidite succession. This succession is not fully preserved as there is a sheared contact between it and the overlying upper greenstone unit. Post-depositional deformation and metamorphic alteration are largely attributed to the Paleoproterozoic Eburnean Orogeny. A first phase of compression was directed along a NW-SE axis and produced a series of isoclinal anticlines and synclines (F1) with NE-SW striking axial planes. This was followed by thrusting between the anticlines and synclines. The age of this deformation and closely associated greenschist metamorphism can be accurately constrained between 2.09 Ga and 2.07 Ga. E-W oriented oblique listric faulting has a prominent effect on the appearance of the Nsuta manganese deposit, as it produced a series of imbricate fault blocks dipping to the north. Associated with this period of deformation is small-scale cross folding with axes plunging to the east (F2). The faults post-date the Eburnean Orogeny and must be associated with a second major tectonic event. Finally, a NNE-SSW striking normal fault, locally known as the German Line, caused further block rotation, notably in the northern parts of the mining concession. Late Mesozoic deep lateritic weathering and incision of the lateritic peneplane by modern rivers have resulted in the complex dissected appearance of the Nsuta orebody. However, based on the detailed structural analysis provided in this study, a feasible target for future exploration of manganese ore buried beneath Late Mesozoic and Cenozoic sediments and soils, has been identified. This target is located to the west of Hills A and B. / Dr. J.M. Huizenga Prof. Nic Beukes Prof. J. Gutzmer
80

A study of the structural geology of an area between the Neusspruit shear zone and the Brakfontein shear zone near Kakamas, Northern Cape.

Shunqukela, Tokozani January 2014 (has links)
>Magister Scientiae - MSc / The study area Koekoeb B is a farm that falls under the Kakamas Terrane which in turn falls under the Gordonia Subprovince in the Namaqua-Natal Metamorphic Province, South Africa. This area was chosen due to lack in literature about its lithology. Koekoeb B is comprised of metasedimentary rocks of the Biesje Poort Subgroup and granitoids of the Keimoes Suite. The Kakamas Terrane was deposited in an intracratonic basin between the Kaapvaal Craton and the Namaqua continental mass. The sediments were buried with time and experienced metamorphism due to burial pressures and temperatures. The area experienced folding as a result of the collision of the newly formed Kakamas Terrane and the Bushmanland segment with the Kaapvaal Craton during a Wilson Cycle. During subduction and collision the metasedimentary rocks were intruded by what is known as the Keimoes Suite. The most abundant intrusive rock in Koekoeb B is the Friersdale Charnockite. It is considered the youngest with Rb-Sr ages around 1080-1090 Ma. The Gordonia Subprovince experienced such intense deformation that continuous folds formed and there is even evidence of parasitic folds. Northwest striking shear zones developed as a result of the continued compression of the Namaqua mass with the adjacent north easterly Kaapvaal Craton. The folds and shear zones formed under four major deformational events Two months were spent acquiring orientation data (direction of dip and dip) in the field. A Clar compass was used to measure the dip direction and dip readings of bedding, cleavage, joints and lineations. The orientation data was imported into Move® software to create a geological map. Samples collected from the field were used to produce thin sections for petrography studies using the petrographic microscope. Conclusions were drawn from the analysis of the data. Koekoeb B experienced regional metamorphism and folding when the Kakamas Terrane collided with the Kaapvaal Craton. The area was subdivided into four subareas based on the strike and dip data generated on the geological map. The synoptic β-axis diagram determined that the subareas are of the same generation but the fold axes orientations vary slightly. Because the study area did not include the shear zones no conclusive reason can be given but it can be assumed that the variation is due to movement along the shear zone or as a result of the intrusion of the Keimoes Suite. The area later experienced brittle deformation which is evident from the large number of joints found; the joints cut across the folds and show a different stress regime from the folds. Conjugate joints were observed on the field and plotted on stereonets. The results showed a vertical sigma two which confirmed that Koekoeb had been affected not only by compression tectonics but by the strike-slip movement on the shear zone.

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