Dissertations / Theses: 'Stratigraphy geology - Cenozoic'

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Young, Jennifer Leigh. "The stratigraphy and structural history of the Mesozoic and Cenozoic of the central Nova Scotian Slope, Eastern Canada /." Internet access available to MUN users only, 2005. http://collections.mun.ca/u?/theses,111328.

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Elferink, Lisa. "The cenozoic stratigraphy and associated heavy mineral palaeo-placer deposit on Geelwal Karoo : West Coast, South Africa." Thesis, Stellenbosch : Stellenbosch University, 2005. http://hdl.handle.net/10019.1/21452.

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ENGLISH ABSTRACT: The farm Geelwal Karoo is situated some 16km north of the Olifants River mouth on the West Coast of South Africa and hosts fluvial, marine and aeolian deposits of post-Gondwana age. The oldest basal fluvial succession, unconformably overlies Proterozoic and Palaeozoic basement rocks and is in turn capped by aeolianite and littoral packages representing two transgressive cycles. The fluvial channel clay succession is deposited in shallow bedrock-incised channels, has a wedge-shape and is deposited parallel to the present coastline. The flow direction is along the coast and the northwardtapering, angular, poorly sorted basal vein-quartz lag indicates a northward palaeo-flow direction. Less than 1% total heavy minerals (THM) is found in the matrix of these gravel units and the heavy mineral suite is distinguished by zircon, pseudorutile and kyanite. The channel clay unit is dominated by an upper, mediumgrained quartzose sand and kaolin clay facies, which shows advanced post-depositional weathering. The fluvial unit is correlated with the channel clay unit of Hondeklip Bay and a Cretaceous age is proposed for the initial channel incision. The two shallow marine successions have been correlated with the Late Miocene, Early Pleistocene, +30m and +50m packages respectively. These marine sediments were first described by John Pether (1994) in the Hondeklip Bay area and were named according to their transgressive maxima. They are transgressive successions arranged en echelon down the coastal bedrock gradient, from oldest and highest to youngest. The offshore environment of the +50m package consists of fine silty sand, which is moderately sorted. The mineral assemblage is dominated by quartz and the average THM is 18%. The inshore environment is distinguished by a single poorly sorted basal cobble lag which shows an overall fining upward succession. The beachface environment is composed of medium to fine-grained sand, which is moderate to well-sorted. Mineral diversity is greatest in the inshore and beachface environments and the average THM for these two units is greater than 35%. The +30m package has been extensively eroded due to its lower erosion and outcrops were sporadic along the coast. The +30m offshore sediments are recognised by fine sediments with high concentrations of glauconite and organic matter. The inshore environment is distinguished by numerous poorly sorted pebble lags with fining upward successions. Both the inshore and beachface units have higher feldspar concentrations than the corresponding +50m units. The average THM for these two units is less than 3%. The aeolianite unit, which comprises several distinct units, extends over the entire length of the study area and is characterized by calcrete and red bed horizons. Colour variations in the otherwise homogeneous unit are due to heavy mineral enrichment and/or different degrees of in situ weathering and cementation. The unit is composed exclusively of fine- to medium-grained sand and the THM concentration averages 9%. This unit is composed of more than one generation of aeolian sand and forms part of an aeolian transport corridor which transported sand from the beach to the interior. The oldest unit has been equated with the Upper Miocene Prospect Hill Formation, whereas the more recent yellow dune sand is equated with the Pleistocene Springfontyn Formation. At Geelwal Karoo, only the heavy sand placer in the +50m package was deemed to be of any economic significance. The average THM of this placer was calculated to be 40% and some 150 thousand tons of Tibearing material can be expected from this succession. This relatively small volume of heavy minerals and extensive cementation however, make this placer a less attractive prospect than the neighbouring Namakwa Sands operation.
AFRIKAANSE OPSOMMING: Die plaas Geelwal Karoo is ongeveer 16km noord van die Olifantsriviermond aan die Weskus van Suid- Afrika geleë en het voorkomste van fluviale, marine en eoliese afsettings van post-Gondwana ouderdom. Die oudste eenheid, ‘n basale fluviale eenheid, oorlê Proterosoiëse en Paleosoiëse plaaslike vloer gesteentes wat op hulle beurt weer bedek word deur eoliese en littorale eenhede verteenwoordigene ven twee transgressiewe siklusse. Die fluviale kanaalklei-opeenvolging, afgeset in vlak ingesnyde rotsbedding-kanale, is wigvormig en is afgeset parallel aan die huidige kuslyn in ‘n alluviale waaier-afsetting. Die vloeirigting was langs die kus en die noorwaards toespitsende, hoekige, swak gesorteerde basale aar-kwarts bodemgruis dui op ‘n noordwaards palaeo-vloeirigting. Minder as 1% totale swaarminerale (TSM) is gevind in die tussenmassa van hierdie gruis-eenhede en die swaarmineraal reeks word onderskei deur sirkoon, pseudo-rutiel en kianiet. Die kanaalklei eenheid word oorheers deur ‘n boonste, medium-korrelrige kwarts-bevattende sand en kaolien kleifasies was dui op gevorderde verwering na afsetting. Die fluviale eenheid word gekorreleer met die kleikanaal en ‘n Kryt-ouderdom word voorgestel vir die aanvanklike insnyding van die kanaal. Die twee vlak marine opeenvolgings word gekorreleer met die Laat Mioseen, vroeg Pleistoseen, naamlik die +30m en +50m eenhede onderskeidelik. Die aflandige omgewing van die +50m eenhied bestaan uit matiggesorteerde, fyn slikkerige sand. Die mineraalversameling word oorheers deur kwarts en die gemiddelde TSM is 18%. Die subgetysone word onderskei deur ‘n enkele swak-gesorteerde gruislaag en is oorwegende opwaarts fynerwordend. Die strandomgewing is goed verteenwordige en bestaan uit matig tot goedgesorteerde medium- tot fynkorrelrige sand. Die grootste mineraal-diversiteit kom voor in die subgety- en strandomgewings en die gemiddelde TSM vir hierdie eenhede is hoër as 35%. As gevolg van algemene erosie kom die +30m eenheid sporadies voor. Die aflandige omgeving is herken deur fyn kleierige of slikkerige sedimente met hoe konsentrasies gloukoniet en organiese materiaal. Die subgetysone omgewing is gekenmerk deur verskeie gruislae wat almal opwaarts fynwordend is. Altwee die subgety- en strandomgewings het hoer feldspar konsentrasies as die +50m eenhede. Die gemiddelde THM vir hierdie enhede is minder as 3%. Die eolitiese eenheid, bestaan uit verskeie duidelik-onderskeibare eenhede, beslaan die totale lengte van die studiegebied en word kenmerk deur uitgebreide kalkreet en rooi-laag horisonne. Kleurverskille in die andersins homogene eenheid kan verklaar word in terme van lae swaarmineraal konsentrasies en/of as gevolg wan verskillende grade van in situ verwering en sementering. Die eenheid bestaan uitsluitlik uit fyntot medium-korrelrige sand en het ‘n gemiddelde TSM konsentrasie van 9%. Die eenheid bestaan uit meer as een generasie eoliese sand en maak deel uit van ‘n eoliese vervoersisteem wat sand vanaf die strand na die binneland vervoer het. Die oudste sande in hierdie eenheid is gekorreleer met die Laat Mioseen Prospect Hill Formasie terwyl die meer onlangse geelduin sand vergelyk word met die Pleistoseen Springbokfontein Formasie. By Geelwal Karoo is slegs die +50m eenhede beskou as economies van belang. Die gemiddelde TSM van hierdie swaarmineraal-ertsligaam is bereken op 40% met ‘n verwagte 150 duisend ton Ti-draende material van die opeenvolging. Die relatiewe klein volume swaarminerale en uitgebreide sementering het tot gevolg dat dit ‘n minder aanloklike proposisie is as die aanliggende Namakwa Sands aanleg.

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Fanton, Jean Carlo Mari 1983. "Reconstruindo as florestas tropicais úmidas do eoceno-oligoceno do sudeste do Brasil (Bacias de Fonseca e Gandarela, Minas Gerais) com folhas de fabaceae, myrtaceae e outras angiospermas : origens da Mata Atlântica." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/287244.

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Orientador: Fresia Soledad Ricardi Tores Branco
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociências
Made available in DSpace on 2018-08-22T19:10:06Z (GMT). No. of bitstreams: 1 Fanton_JeanCarloMari_D.pdf: 19867542 bytes, checksum: 5b38f9327cfcd9fa334e56499a15d4bc (MD5) Previous issue date: 2013
Resumo: Folhas isoladas de angiospermas preservadas em depósitos fluvio-lacustres das bacias de Fonseca e Gandarela foram analisadas visando reconstruir o paleoambiente. Angiospermas são bons indicadores climáticos, pois a distribuição de suas espécies no espaço/tempo e influenciada pelo clima. Localizadas no centro-sul de Minas Gerais, as bacias de Fonseca e Gandarela são grabens encravados no embasamento Pré-Cambriano, depositados nos intervalos Neoeoceno-Eoligoceno e Neoeoceno- Eomioceno (respectivamente), segundo dados paleológicos. Como métodos, alem da morfotipificação, características arquiteturais informativas permitiram identificações taxonômicas com base apenas em folhas. Para estimar as paleotemperaturas, aplicou-se a Analise da Margem Foliar (LMA) utilizando a relação entre a proporção de espécies arbóreas "dicotiledôneas" com margens lisas (pE) e a media anual de temperatura (MAT). Antes, a habilidade de modelos sul-americanos foi testada em florestas atlânticas do sudeste. Devido à pEs altas (0,78-0,87), as temperaturas dos locais quentes-baixos (MAT ? 23°C) foram estimadas corretamente, mas o erro foi maior nos locais frios-elevados (MAT ? 22°C, 610-890 m). Mesmo que linhagens obrigatoriamente lisas estiveram super-representadas tanto nos locais quentes quanto frios (em media 38% das espécies/local), o desenvolvimento de terras altas desde o Neocretaceo e Cenozóico no sudeste inviabiliza hipóteses de tempo insuficiente para a evolução de margens denteadas nas angiospermas adaptadas a altitude. Para Fonseca (40 morfotipos) e Gandarela (20) foram obtidas pEs tão altas (0,90 e 0,95) quanto às de florestas equatoriais amazônicas atuais. MATs ? 24,7°C foram reconstruídas pela maioria dos modelos (em media ?27-28°C), faixa megatermica hoje registrada principalmente em terras-baixas do norte e nordeste do Brasil. Mais da metade dos 25 morfotipos aqui descritos foram identificados em famílias tropicais, como Lauraceae (FS06, GR03 e GR09), Fabaceae (FS01-03, FS05, FS09 e GR08), Combretaceae (FS08) e Myrtaceae (FS11-13 e GR02). Todas são linhagens com uma longa historia evolutiva (no mínimo desde o Paleoceno-Eoceno) no norte (Fabaceae e Lauraceae) e no sul (Myrtaceae) da America do Sul, expondo um antigo legado de tropical idade e influencia floristica mista (boreal-laurasiana e austral-antartica). Hoje no sudeste, tais famílias controlam boa parte dos recursos ecológicos na Mata Atlântica e provavelmente já o faziam nas florestas do Neopaleogeno. Devido à composição e certas condições ambientais compartilhadas, as florestas ombrofilas do compartimento sul da Mata Atlântica (inclusive a Floresta Ombrofila Mista, FOM) são analogias modernas parcialmente comparáveis com Fonseca e Gandarela: temperaturas e pluviosidade elevadas mantendo um dossel sempre-verde e multiestratificado, dominado por angiospermas (Myrtaceae, Lauraceae e Fabaceae) e coníferas austrais (Podocarpaceae e Araucariaceae). Confirmam a reconstrução de florestas tropicais úmidas: (1) o conjunto fisionômico da Formação Fonseca (onde 40- 65% dos morfotipos avaliados têm ápice acuminado, 80-90% margens lisas e 50% notofilo-mesofilos) e (2) a presença de linhagens que demandam umidade e intolerantes ao frio, como podocarpaceas dacrydioides (Dacrydiumites) e mirtaceas como FS13 (identificado em Curitiba), exibindo uma folha acuminada 2× maior que da atual C. prismática, espécie endêmica da FOM. O cenário reconstruído se ajusta aos níveis superiores de CO2 atmosférico, maior zona tropical e invernos relativamente brandos do final do Paleogeno
Abstract: Isolated fossil angiosperm leaves preserved in fluvial-lacustrine deposits from the Fonseca and Gandarela basins were analyzed to reconstruct the paleoenvironment. Angiosperms are good climatic indicators since the species distribution in space/time is influenced by the climate. Located in central-southern part of the State of Minas Gerais, the Fonseca and Gandarela basins are grabens embedded in the Precambrian basement, deposited during the Late Eocene-Early Oligocene interval, according to palynological data. As methods, informative architecture characteristics allowed taxonomic identifications solely on the basis of leaves. To estimate paleotemperatures, the Leaf Margin Analysis (LMA) was applied, based on the relationship between the proportion of untoothed woody "dicot" species (pE) and mean annual temperature (MAT). Before, the ability of South American models was tested on modern sites of Atlantic forests from southeastern Brazil. Because of high pEs (0,78-0,87), temperatures of the low-elevation sites (MAT ? 23°C) were predicted accurately, but the error was greater in the high-elevation ones (MAT ? 22°C, 610-890 m). Although obligate untoothed lineages were richly represented in low and high-temperature sites (in average 38% of the species per site), the development of highlands in southeastern Brazil since the Late Cretaceous and Cenozoic invalidate hypotheses about an insufficient time to evolve teeth in angiosperms adapted to high-elevations. Both fossil floras Fonseca (40 morphotypes) and Gandarela (20) showed pEs (0,90 and 0,95) so high as observed in Amazonian equatorial rainforests. MATs ? 24,7°C were yielded for the majority of the models (in average ?27-28°C), isotherm today registered mainly in lowlands from northern Brazil. Over half of the morphotypes described were identified in families essentially tropical, such as Lauraceae (FS06, GR03 and GR09), Fabaceae (FS01-03, FS05, FS09 and GR08), Combretaceae (FS08) and Myrtaceae (FS11-13 and GR02). All these lineages have a long evolutionary history (since at least the Paleocene- Eocene) in the north (Fabaceae and Lauraceae) and south (Myrtaceae) of South America, revealing an antique legacy of tropicality and mixed floristic influence from boreal-laurasian and austral-Antarctic regions. Today, such families have controlled a major portion of the ecological resources in the Atlantic forests from southeastern Brazil probably retaining dominance since the Paleogene. Similar composition and some environmental aspects suggest that the rainforests from the southern Atlantic block (including Araucaria rainforest) are the closest living analogues to the Fonseca and Gandarela extinct vegetation: high temperatures and heavy rainfall sustaining an evergreen and multilayered canopy dominated by angiosperms (Myrtaceae, Lauraceae and Fabaceae) and austral conifers (Podocarpaceae and Araucariaceae). Additional evidence supporting the tropical rainforest hypothesis is: (1) the Fonseca Formation leaf physiognomy (40-65% of the morphotypes evaluated have drip tips, 80-90% untoothed margins and 50% are notophyll-mesophyll), and (2) the presence of water-demanding and coldintolerant lineages, such as dacrydioid podocarps (Dacrydiumites) and the Myrtaceae morphotype FS13 (identified as Curitiba), which bears an acuminate leaf 2× longer than the extant C. prismatica. The paleoenvironment reconstructed agree with the higher atmospheric CO2 levels, the wider Tropical zone and the relatively mild winters during the Late Paleogene
Doutorado
Geologia e Recursos Naturais
Doutor em Ciências

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Hare, Alison (Alison Grace) 1976. "The stratigraphy and evolution of the late Cenozoic, intra-plate Werribee Plains basaltic lava flow-field, Newer Volcanic Province, Victoria, Australia." Monash University, School of Geosciences, 2002. http://arrow.monash.edu.au/hdl/1959.1/7586.

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McKean, Adam Paul. "Volcanic stratigraphy and a kinematic analysis of NE-trending faults of Allens Ranch 7.5' quadrangle, Utah County, Utah." BYU ScholarsArchive, 2010. https://scholarsarchive.byu.edu/etd/2410.

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The mineral resources of the Tintic Mining District are influenced by three major events in its geologic history; the Mesozoic Sevier Orogeny, Paleogene volcanism and Late Neogene Basin and Range extension. In this paper a detailed analysis of each these geologic events is presented to help us understand the structural host, mineralization and exhumation of the Tintic Mining District ore. A kinematic analysis of the faults was completed to determine the origin of NE-trending faults, Sevier Orogeny or Basin and Range extension, in the northern part of the East Tintic Mountains in Allens Ranch 7.5' quadrangle, near the eastern margin of the Great Basin of central Utah. The structural history of the NE-trending faults found in the quadrangle was reconstructed to determine stress directions and fault kinematics. Maximum paleostress direction for the East Tintic fold and thrust system is between 80º–100º with fold axes oriented at ~350º. For example, the Gardison Ridge and Tintic Prince faults are NE-trending right-lateral transverse faults that formed at ~30º to paleostress directions similar to those of the Sevier Orogeny. The dominant NE-trending faults in the region are likely due to (1) differential shortening during progressive orocline development, (2) the pre-deformational Pennsylvanian-Permian Oquirrh basin geometry, and (3) the influence of the Leamington transverse zones of the Provo salient. Conversely, mixed paleostress directions for the north-trending Tintic Davis Canyon fault show it is a Basin and Range extension-related normal fault that may have originated as a Sevier related fault. Other N-trending faults within the quadrangle are only related to Basin and Range extension. However, large offset, range-bounding faults are buried by valley fill throughout the quadrangle and no young fault scarps are identified cutting Lake Bonneville deposits. An Oligocene to Miocene suite of extrusive volcanic units in the quadrangle correlates well with those of the East Tintic and Soldiers Pass volcanic fields. The Paleogene volcanic section is dominated by a suite of high-K calc-alkaline extrusive rocks (35 to 32 Ma). This intermediate to silicic sequence was followed by eruption of the mildly alkaline Mosida Basalt during the Miocene (19.5 Ma) marking the transition from subduction-related intermediate and silicic volcanism to extension-related mafic volcanism in the eastern Great Basin.

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Verdel, Charles Steven Eiler John Eiler John. "I. Cenozoic geology of Iran : an integrated study of extensional tectonics and related volcanism. II. Ediacaran stratigraphy of the North American cordillera : new observations from eastern California and northern Utah /." Diss., Pasadena, Calif. : California Institute of Technology, 2009. http://resolver.caltech.edu/CaltechETD:etd-09182008-092505.

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Beard, Linda Sue. "Precambrian Geology of the Cottonwood Cliffs Area, Mohave County, Arizona." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/244095.

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A belt of Early Proterozoic rocks crops out in the Cottonwood Cliffs area, northwest Arizona. The belt contains an eastern and a western assemblage separated by the Slate Mountain fault. The western assemblage consists of mafic to felsic metavolcanic rocks, metapelites, and metaconglomerates. The eastern assemblage consists of phyllites, felsic to intermediate metavolcanic rocks, metagraywackes, and metagabbro bodies. The belt is bounded to the east by foliated granodiorite. The Valentine granite intruded the belt on the west and north. Steeply-plunging lineations and fold axes, and northeast-trending vertical foliation dominate the structural fabric. The regional elongation direction is near-vertical, as indicated by mineral and pebble lineations, and is parallel to fold axes. Although only one deformational event is evident, the intensity of that event may have obliterated evidence of any earlier deformation. Tertiary basalts and the Peach Springs Tuff locally overly the metamorphic rocks. Cenozoic normal faults in the area are mostly of minor displacement.

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Li, Yongxiang. "Paleomagnetism of late paleozoic to cenozoic rocks in Hong Kong, China /." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21490107.

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Pak, Ŭn-ju. "Cenozoic geohistory of the southwestern margin of the Ulleung basin, East Sea." [S.l. : s.n.], 1986. http://catalog.hathitrust.org/api/volumes/oclc/53229626.html.

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Baker, Joel Allen. "Stratigraphy, chronology and geochemistry of cenozoc volcanism in Western Yemen." Thesis, Royal Holloway, University of London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299765.

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Liu, Junsuo. "Pétrogénèse des roches alcalines mafiques d'âge méso-cénozoique dans les provinces de Hunan et Guangxi, Chine septentrionale = petrogenesis of the mesosoic-cenozoic mafic alkaline subvolcanic rocks in Hunan-Guangxi provinces, southern China /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1992. http://theses.uqac.ca.

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Li, Yongxiang, and 李永祥. "Paleomagnetism of late paleozoic to cenozoic rocks in Hong Kong,China." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31223096.

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McCune, Julian Glenn. "Cenozoic sedimentary evolution of the Helmville Basin, west-central Montana." CONNECT TO THIS TITLE ONLINE, 2008. http://etd.lib.umt.edu/theses/available/etd-05282008-101831/.

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Mitchell, Sara Gran. "Late-Cenozoic topographic evolution of the Cascade Range, Washington State, USA /." Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/6713.

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Heil, Clifford William. "Paleo-and environmental magnetic studies of late Cenozoic estuarine, lacustrine, and terrestrial sediments /." View online ; access limited to URI, 2008. http://0-digitalcommons.uri.edu.helin.uri.edu/dissertations/AAI3314457.

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Paul, Jonathan David. "Dynamic topography and drainage of Africa and Madagascar." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708248.

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Holmes, Jonathan Anthony. "Pliocene and Quaternary environmental change in Kashmir, north-west Himalaya." Thesis, University of Oxford, 1989. http://ora.ox.ac.uk/objects/uuid:e9bb6cf8-93a8-4471-9c55-7ed84044dc3c.

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Late Cainozoic environmental changes in Kashmir (33°30' to 34°30' N: 74°10' to 75°30' E) have been reconstructed using a range of techniques. The sedimentary record in Kashmir consists of a thick (>1000m) basin-fill sequence known as the Karewa group, together with glacial and related sediments in the surrounding mountain flanks. The Karewa sediments are fluviolacustrine in origin and comprise alternations of conglomerates, sands and clayey silts. Work on the lower Karewa formation, which has previously been dated palaeomagnetically to between 4 and 0.4 MaBP, involved the semi- quantitative analysis of clay-mineral assemblages by X-ray diffraction.The clay minerals in the lower Karewa mudstones are interpreted as detrital clays which reflect weathering within Kashmir basin. The analyses showed a change in clay mineralogy between about 2.5 and 2.3MaBP, from abundant kaolinite to abundant smectite. Work on the upper Karewa formation involved field description and mapping of facies, sedimentological analysis, dating using thermoluminescence (TL) and amino-acid racemization, and analysis of ostracod assemblages from lacustrine sediments. Areal restriction of the lake in Kashmir occurred about 0.4MaBP with the rapid uplift of the Pir Panjal Range. Sedimentological data show that aeolian dust formed a major input into the lake. Ostracod assemblages show that the lake itself was cool, shallow, alkaline and had abundant plant macrophytes, The lake drained between 120 and SOkaBP. Stratigraphical, sedimentological and faunal evidence suggests that this was a result of tectonically-induced drainage rather than climatically-induced desiccation. The glacial history of the surrounding mountain flanks was reconstructed by field mapping of glacial sediments and dated using TL and radiocarbon methods. Present and past patterns of glaciation wore assessed by the determination of equilibrium-line altitudes (ELAs), glaciation thresholds (GTs) and cirque aJtitudes. Glaciers extended to 2150 m a.s.l in the Great Himalayan flank and 2600 m a.s.l. in the Pir Panjal. There is evidence for only 2 pre-Holucene advances in Kashmir, the older of which predates 35kaBP. Present patterns of glacierization indicate a SW to NE rise in the height of ELAs and GTs suggesting topographic and precipitation control. An apparent reversal of trends during the past is explained by Quaternary uplift of the Pir Panjal Range.

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Hoang, Long Van. "Cenozoic climate-tectonic interactions preserved in the Song Hong-Yinggehai and Qiongdongnan Sedimentary Basins, South China Sea." Thesis, University of Aberdeen, 2010. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=137011.

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In this thesis, I present new results based on 2D multi-channel seismic data of the Song Hong-Yinggehai and Qiongdongnan Basins, geochemical data derived from ODP Site 1148, and sediment provenance analysis of modern sediment and Cenozoic sedimentary rocks collected along the Red River system. The Song Hong-Yinggehai Basin started opening after ~50 Ma but strong subsidence, triggered by motion on the Red River Fault, only occurred after ~34 Ma. This process was followed by thermal subsidence after ~21 Ma. In contrast, the formation the Qiongdongnan Basin is believed to be related to the development of the northern rifted margin of the South China Sea. Sediment budget estimates, coupled with geochemical data show that chemical weathering gradually decreased after ~25 Ma, while physical erosion became stronger. These data also suggest a period of the monsoon enhancement (~15-10 Ma), although with a likely initial East Asia monsoon strengthening ~23 Ma. U-Pb zircon dating coupled with Hf isotopes, muscovite Ar-Ar dating, bulk sediment Nd isotope and heavy mineral analysis allow me to draw the following points: (1) if the headwaters of the modern Yangtze, Mekong and Salween Rivers were ever connected to the palaeo-Red River then they were disconnected from the Red River no later than the Middle Miocene; (2) The palaeo-Red River flowed northeast of the Day Nui Con Voi during the Miocene and did not flow via Lao Cai and southwest of the range as it is observed today; (3) the Yangtze Craton and the Songpan Garze Block are the most important source regions to the Red River; (4) apart from the main Red River trunk, the Lo River is the most important sediment contributor to the Red River system, while the Da River is only a minor contributor.

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Blankenau, James J. "Cenozoic Structural and Stratigraphic Evolution of the Southeastern Salmon Basin, East-Central Idaho." DigitalCommons@USU, 1999. https://digitalcommons.usu.edu/etd/6711.

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The southeastern Salmon basin (SB) of east-central Idaho is a complex east-dipping half graben containing four unconformity-bounded sequences of Tertiary volcanic, alluvial fan, lacustrine, and fluvial deposits. From oldest to youngest these are the Challis volcanic group, sedimentary rocks of Tendoy (new name), sedimentary rocks of Sacajaweja (new name), and Quaternary-Tertiary deposits . The thick sequence of volcanic rocks was deposited in a southeast-trending paleovalley . New mapping, cross-cutting relationships, 40Ar/39Ar age determinations, and angular unconformities show that the SB has experienced at least four episodes of extension, and that it lies in the core of an Eocene to Oligocene rift zone. T he largest episodes of extension in the SB were the second and third episodes of extension. These were responsible for the deposition of the sedimentary rocks of Tendoy and sedimentary rocks of Sacajaweja, respectively. Episode 2 occurred along the west southwest-dipping Agency Yearian fault, and can be attributed to gravitational collapse of the Sevier fold and thrust belt between the late middle Eocene and Oligocene (?). Several southwest-dipping low-angle normal faults were active during the third episode and may have been active into early Miocene time. The third episode of extension reflects continued gravitational collapse. Also active during episode 3 was the Salmon basin detachment fault, which is interpreted as a regional detachment based on its lateral extent and low dip angle (11°). Extensional folds are common in the southeastern Salmon basin and represent at least two generations of folds. Interference between northnortheast and southeast-trending folds locally produced dome and basin features. The folds are typically open to gentle, and have a maximum fold height of 2.2 km. Most of the folds are fault-bend folds, and some are associated with growth strata. The development of the Tendoy anticline and Pattee Creek syncline in the hanging wall of the Agency-Yearian fault produced two depositional basins during the deposition of the sedimentary rocks of Tendoy. Facies patterns and megabreccia deposits in the subbasins indicate that there was considerable topography along the margins of the subbasins .

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Nelson, Faye Elizabeth, and University of Lethbridge Faculty of Arts and Science. "Late cenozoic magnetostratigraphy of Selkirk volcanics and associated sediments, west-central Yukon." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2006, 2006. http://hdl.handle.net/10133/357.

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Brunhes, Matuyama, Kaena and Mammoth age basaltic lava (Selkirk Volcanics - TQS) as well as interbedded sediments were sampled in west-central Yukon Territory, Canada. Paleomagnetic sampling of basalt mapped as TQS along a 370 kilometre transect suggests that early eruptions of TQS occurred coevally over a significant distance to the north of Fort Selkirk. Basal basalt at Ne Ch'e Ddhawa pre-dates continental glaciation in Yukon and is older than the Fort Selkirk Vent (Lower Mushroom), previously thought to be the oldest eruptive vent at Fort Selkirk. The high confining pressures required to form pillow lava suggest subglacial eruptions at Mushroom section. An Early Pleistocene Fort Selkirk glaciation sequence (till and outwash) was reversely magnetized and assigned to the Late Matuyama chron between oxygen isotope stages 62 and 56 inclusive. A lateral moraine on Ne Ch'e Ddhawa was reversely magnetized and therefore assigned to one of the younger Pre-Reid glaciations. i
xi, 123 leaves : ill. (some col.) ; 29 cm.

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Wilson, Jonathan William Peter. "Cenozoic epeirogeny of the Middle East and equatorial West Africa." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709049.

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Onuba, Leonard Nnaemeka. "A preliminary analysis of the basement structure of the Cenozoic Niger Delta basin : insights from high-resolution potential field data." Thesis, University of Aberdeen, 2016. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=231939.

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Bond, Jeffrey David. "Late Cenozoic history of McQuesten map area, Yukon Territory, with applications to placer gold research." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq21154.pdf.

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24

Le, Roux F. G. "The lithostratigraphy of Cenozoic deposits along the south-east Cape coast as related to sea-level changes." Thesis, Stellenbosch : Stellenbosch University, 1989. http://hdl.handle.net/10019.1/67134.

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Thesis (MSc)--University of Stellenbosch, 1989.
AFRIKAANSE OPSOMMING: Senosoiese sedimente langs die suidooskus van die Kaapprovinsie is periodiek deur verskeie outeurs vir meer as 'n eeu bestudeer. In hierdie aanbieding word die Iiteratuur saamgevat en vele dubbelsinnige stratigrafiese onderverdelings en definisies opgeklaar. Die Senosoiese afsettings kan volgens oorsprong geklassifiseer word as marien, eolies en fluviaal. Die mariene afsettings, synde strand-, nabystrand-, estuarien of lagunale afsettings geassosieerd met transgressiewe/ regressiewe kusIyne, word nou op grond van kenmerkende litologiese, paleontologiese sowel as ouderdomsverskille onderverdeel in die Paleogeen Bathurst, Neogeen Alexandria en Kwaternere Salnova Foraasies. Die Laat-Plioseen tot Vroeg-Pleistoseen Nanaga Formasie, Middel- tot Laat- Pleistoseen Nahoon Formasie en die Holoseen Schel• Hoek Formasie vorm die kus-eoliese afsettings. AI die mariene en marienverwante (eoliese} formasies, gekenmerk deur kalkige klastiese afsettings, is saamgegroepeer in 'n nuutgedefinieerde Algoa Groep. Fluviale afsettings word onderverdeel in die Martindale, Kinkelbos, Bluewater Bay, Kudus Kloof en Sunland Formasies. Die onderskeie afsettings word gekorreleer met verskillende seevlakstande deur geologiese tye. Die vroegste Senosoiese transgressiewe/regressiewe siklus het in die Vroeg-Paleoseen begin en die hoogste aangetekende elevasie vir die era bereik. Die Bathurst Formasie is waarskynlik gedurende hierdie regressie afgeset. 'n Tweed~ kleiner transgressie/ regressiesiklus het plaasgevind gedurende die Laat-Eoseen tot Vroeg-Oligoseen. Sover tans bekend, kan geen afsetting in die dagsoomgebied van die Algoa Groep definitief met hierdie siklus in verband gebring word nie. Die volgende siklus, wat 'n transgressiewe maksimum van c. 250 m bereik het, het begin in die Middel-Mioseen en verstryk in die Vroee Plioseen. Mariene planasie van die kusplatform het gedurende die transgressie plaasgevind terwyl die Alexandria Formasie wat tans bo 120 m geleë is, gedurende die regressie afgeset is. Die Vroeg-Plioseen transgressie het waarskynlik 'n maksimum huidige hoogte van c. 120 m bereik, waartydens o.a. die 120 m branderstoep en "Humansdorpterras" gekerf is. Die Alexandria Formasie tans geleë tussen 60 en 120 m, is afgeset gedurende die Laat-Plioseen regressie. Hierdie regressie het verskeie relatief lang stilstande, wat waarskynlik die 106-m, 90- tot 100-m en 84-m branderstoepe verklaar, ondervind. Selfs die 60-m en 52-m kuslyne kon tydens hierdie regressie gevorm het. Voorlopige paleontologiese getuienis dui egter daarop dat die 60-m kuslyn 'n transgressiewe maksimum van 'n daaropvolgende siklus verteenwoordig, gevolg deur 'n regressie met minstens een beduidende stilstand by 52 m. Die Alexandria Formasie geleë tussen c. 60 en 30 m, is waarskynlik gedurende hierdie regressie gedeponeer, waartydens ook die Bluewater Bay, Kinkelbos en Kudus Kloof Formasies afgeset is. Gedurende die Kwaternêre transgressie/regressiesiklusse, waarvan minstens vier aangedui word, is die Salnova Formasie (afwesig bo 30 m) afgeset. Die Nahoon Formasie, wat ook op groot skaal op die kontinentale bank ontwikkel is, is gedeponeer gedurende die laaste twee Pleistoseen glasiale toe seevlakke tot benede -100 m gedaal het. Die Schelm Hoek Formasie wat tans nog afgeset word, het ontstaan uit die transgressiewe maksimum van die Flandriese transgressie aan die begin van die Holoseen.
ENGLISH ABSTRACT: Cenozoic sediments along the south-east coast of the Cape Province have been studied intermittently for more than a century by various authors. In this presentation the literature is reviewed and many ambiguous stratigraphic subdivisions and definitions are clarified. The Cenozoic deposits can be classified, according to origin, as marine, aeolian and fluvial. The marine deposits, being lagoonal deposits either beach, nearshore, estuarine or associated with transgressive/regressive shorelines, are now subdivided on the grounds of distinct lithological, palaeontological as well as age differences into the Palaeogene Bathurst, Neogene Alexandria and Quaternary Salnova Formations. The Late Pliocene to Early Pleistocene Nanaga Formation, the Hiddle to Late Pleistocene Nahoon Formation and the Holocene Schelm Hoek Formation constitute the coastal and marine-related aeolian deposits. All the marine (aeolian) formations, which are characterised by calcareous clastics, have been grouped together in a newly defined Algoa Group. Fluvial deposits are subdivided into the Martindale, Kinkelbos, Bluewater Bay, Kudus Kloof and Sunland Formations. The various deposits are correlated with different stands of sea-level through geological time. The earliest Cenozoic transgression/regression cycle started in the Early Palaeocene and reached the highest recorded altitude for the era. The Bathurst Formation was probably deposited during this regression. A second lesser transgression/regression cycle occurred in the Late Eocene to Early Oligocene. As far as is presently known, no deposit in the outcrop area of the Algoa Group can be definitely related to this cycle. The next cycle, which reached a transgressive maximum of c. 250 m, started in the Middle Miocene and terminated in the Early Pliocene. Marine planation of the coastal platform took place during the transgression, whilst the Alexandria Formation presently situated above 120 m, was deposited during the regression. The Early Pliocene transgression is considered to have reached a maximum present-day elevation of c. 120 m, during which the 120 m marine bench and "Humansdorp Terrace", amongst others, were carved. The Alexandria Formation presently situated between 60 and 120 m, was deposited during the Late Pliocene regression, which experienced several relatively long stillstands which probably account for the 106 m, 90 t.o 100 m and 8.4 m benches. Even the 60 m- and 52 m-shorelines could have been formed during this regression. Preliminary palaeontological evidence, however, suggests that the 60 m shoreline represents a transgressive maximum of a subsequent cycle followed by a regression with at least one significant stillstand at 52 m. The Alexandria Formation situated between c. 60 and 30 m, was probably deposited during this regression, which also saw the deposition of the Bluewater Bay, Kinkelbos and Kudus Kloof Formations. During the Quaternary transgression/regression cycles, of which at least four are indicated, the Salnova Formation (absent above 30 m) was deposited. The Nahoon Formation, which is also extensively developed on the continental shelf, was deposited during the last two Pleistocene glacials, when sea-levels receded to less than -100 m. The Schelm Hoek Formation, which is still being deposited, originated from the transgressive maximum of the Flandrian transgression at the start of the Holocene.

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Chan, On-kee Angel, and 陳安琪. "Miocene collision related conglomerates, south Tibet." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B30736870.

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Valero, Montesa Luis. "Controls on the development of sedimentary sequences in continental basins: examples from the Cenozoic of Iberia." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/396615.

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The first goal of this thesis is to provide accurate and complete age models for key basins of Iberia. The Ebro, Almazán, and As Pontes basins were chosen because of their geological importance and because long sections with overlapping ages were available. All the studied records encompass a long time span (>7-Ma), which may be used for research in a wide range of time-scales. In particular, we focused in assessing the impact in the stratigraphy of the very long-term Milankovitch cycles (> 1Ma) and their relationship in the generation of sedimentary sequences at basin scales. Disentangling such relationship may shed light into the tectonic or climatic origin of observed sedimentary sequences. In parallel, the development of age models allows for a precise quantification of sedimentation rates. The results of this PhD project provide insights on the expression of the Milankovitch cycles in continental basins and also on the relationship between accommodation and sediment supply in the development of sedimentary sequences. Our data together with results from other case studies allows for a discussion about the pathways in which Milankovitch cycles affected the continental sedimentary records through a mass-balance approach. In order to undertake these subjects, three independent studies have been carried out In the Ebro Basin, it has been shown that the location of the lacustrine depocenters was conditioned by the migration of the subsidence distribution due to the thrust-belt structuring and the subsequent foreland evolution. Despite tectonics, the superimposed signal of climate was found to be the main cause of lake level variation. Times of orbital eccentricity maxima are associated to lake level highstands, indicating a positive water balance. Intervals with high-amplitude precession cycles, due to eccentricity modulation, are seen as the drivers of water recharge. Oppositely to the Ebro Basin, the As Pontes Basin is a small basin that lacked a central lake system during the studied interval. The occurrence of peatlands in the distal parts, made the system very sensitive to shifts in the terrigenous input. In As Pontes, it has been shown that climatic stability at times of eccentricity minima appears associated to peat development and burial. This is likely more linked to resilient vegetation cover and equilibrium geomorphologic profiles, which reduced the sediment supply. The cyclic arrangement in the depocenters was shaped by changes in the sediment supply, which may increase, and dilute the accumulation of organic matter, rather than by variable lake level. Despite there is not enough resolution as to test for precession or obliquity, the stacking pattern shows no evidence of these higher frequency orbital cycles. It suggests a control of eccentricity on the expression of orbital forcing in a clastic-dominated system. The analysis carried out in the Almazán Basin illustrates how the distribution of the depositional elements, their internal architecture, and the sedimentation rates are consequence of variations in the AS/SS ratio (Accommodation/Sediment supply). This makes the AS/SS ratio an excellent marker for the mass balance variations, the distribution of the total volume of sediment along a basin, allowing for a quantification of the response of a basin to extrinsic changes, which are mainly climate and tectonics. Although if a single depositional element is analysed at short time scales, the ratio also may include the autogenic variations.
Aquesta tesi te com a principal objectiu datar conques Cenozoiques clau en l’evolució geològica de la Península Ibèrica mitjançant magneto- i astrocronologies. La tesis està constituïda per una recopilació d’articles. La unió dels diferents treballs realitzats dóna lloc a uns resultats i discussió a on s’aborden les diferents camins mitjançant els quals els registres sedimentaris poden expressar litològicament els cicles de Milankovitch, claus en la generació de seqüències sedimentaries. Tres conques de la península Ibérica, Ebre, Almazán i As Pontes, han estat estudiades. Per separat, els resultats mostren que les seqüències sedimentaries a les parts centrals de la conca de l’Ebre estan relacionades amb el cicle orbital de 2.4 milions d’anys. A on els màxims d’excentricitat estan relacionats amb la expansió dels sistemes lacustres. A la conca d’As Pontes els canvis de la excentricitat orbital també s’han identificat com a causants de les seqüències. Em aquest cas, els mínims d’excentricitat de 400 mil anys i de 2,4 Milions d’anys semblen ser els precursors dels nivells de lignits. A la conca d’Almazán, degut a la deformació produïda per estructures, no hi trobem l’empremta dels cicles orbitals. El que sí s’observa es una relació entre les taxes de sedimentació i l’arquitectura i la distribució dels elements deposicionals. Els resultats finals indiquen que a banda de un règim climàtic concret la morfologia i característiques de les conques sedimentaries son elements claus en quant a l’expressió dels cicles de Milankovitch.

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Arriagada, César. "Rotations tectoniques et déformation de l'avant arc des Andes centrales au cours du Cénozoïque = Rotaciones tectónicas y deformación del antearco en los Andes centrales durante el cenozoico /." Rennes : Géosciences Rennes, Université de Rennes 1, 2004. http://catalogue.bnf.fr/ark:/12148/cb392302035.

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Th. doct.--Sci. de la terre--Rennes 1, 2003. Th. doct.--Ciencias, mention Geologia--Universidad de Chile, 2003.
Mention parallèle de titre ou de responsabilité : Rotaciones tectónicas y deformación del antearco en los Andes centrales durante el cenozoico. Textes en français et en anglais. Bibliogr. p. 301-308. Notes bibliogr. Résumé en français, en anglais et en espagnol.

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Berger, Julien. "Les associations de roches basiques - ultrabasiques néoprotérozoïques d'Amalaoulou (Gourma, Mali), du Tassendjanet (Hoggar occidental, Algérie) et cénozoïques du Saghro (Anti-Atlas, Maroc): témoins de l'évolution géodynamique de la ceinture péri-cratonique ouest-africaine." Doctoral thesis, Universite Libre de Bruxelles, 2008. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210499.

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Ce travail retrace l’évolution de la suture panafricaine le long de l’axe Anti-Atlas, Hoggar occidental, Gourma, depuis l’activité tectono-magmatique néoprotérozoïque pré-panafricaine jusqu’à l’activité magmatique anorogénique cénozoïque via l’étude de quatre massifs basiques-ultrabasiques disposés à la périphérie du craton ouest-africain.

Le massif d’Amalaoulaou (Gourma, Mali) est interprété comme la racine d’un arc intra-océanique ayant enregistré la mise en place de magmas basiques (unité des métagabbros) à un stade immature de l’évolution de l’arc (subduction naissante) vers 800-790 Ma. Les gabbros quartziques (~720 Ma) et les gabbros à hornblende de l’unité supérieure ont des signatures de magmas d’arc plus franche, témoins d’une source mantellique plus enrichie par l’apport de la plaque océanique plongeante. Les métagabbros sont ensuite affectés par une recristallisation et localement par une anatexie en conditions du faciès granulitique. De nombreuses veines leucocrates se développent à ce stade, ce sont principalement des anorthosites et des tonalites (mises en place vers 660 Ma) provenant de la fusion partielle des métagabbros (850°C-1000°C, P>10 kbar). Cette fusion génère également des résidus denses à grenat-clinopyroxène-rutile, associations fréquemment présentes dans les racines d’arcs plus récents et reflétant la maturation de l’arc. L’arc d’Amalaoulaou est ensuite exhumé et charrié sur le craton ouest-africain dans des conditions de basse température et moyenne pression (550°C, 6-9 kbar), probablement au même moment que l’exhumation des éclogites du Gourma (~620 Ma).

L ‘épisode de subduction océanique est suivi par la subduction continentale dans le Gourma et le Hoggar occidental. Les éclogites/amphibolites de Tiléouine et Tin Zebbane (Hoggar occidental) sont des métabasaltes tholéiitiques enrichis et alcalins intracontinentaux ayant plongé à 60 km de profondeur (600°C, 17 kbar) lors de la subduction d’une partie du terrane du Tassendjanet. Même si la nature géochimique du protolithe est encore reconnaissable, ces métabasaltes ont subi une différenciation chimique lors de la recristallisation à haute pression par interaction avec les fluides issus de la déshydratation des métasédiments. L’exhumation (615-600 Ma) se fait relativement lentement, ce qui induit un rééquilibrage thermique (750°C, ~10 kbar) avant l’exhumation à basse température (660 °C, 7-8 kbar) précédant de peu voire synchrone à la phase collisionnelle.

L’intrusion basique-ultrabasique de Tiléouine marque la fin de la collision panafricaine dans le Hoggar occidental (600-590 Ma). C’est une ancienne chambre magmatique différenciée, mise en place entre 10 et 20 km de profondeur, et montrant une évolution magmatique depuis des cumulats ultramafiques riches en olivine, spinelle et pyroxène vers des gabbros riches en plagioclase. Le magma parental est d’affinité tholéiitique enrichie et tire probablement sa source de la lithosphère sous-continentale. La mise en place de cette intrusion est contemporaine d’un contexte tectonique transtensif induisant un amincissement lithosphérique au niveau du Tassendjanet.

Cette suture péri-cratonique est réactivée au Cénozoïque, lors de la convergence Afrique-Europe, ce qui se marque par la mise en place de laves alcalines, notamment dans l'Est de l’Anti-Atlas marocain (Saghro :10-3 Ma). Les néphélinites du Saghro sont issues de faibles taux de fusion partielle d’une source mantellique contenant un composant HIMU et localisée à la limite asthénosphère/lithosphère (70-100 km sous l’Anti-Atlas). La cristallisation fractionnée de ces magmas génère des phonolites, par fractionnement de feldspath, néphéline, apatite et sphène, principalement. L’étape finale de différenciation se marque par la formation de phases peu communes comme la hainite et la lorenzenite. Ces magmas se sont mis en place à la faveur de fentes de tension et de fractures ouvertes ayant la même orientation que la contrainte principale au Mio-Pliocène.

Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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Brezina, Cynthia A. "The detrital mineral record of Cenozoic sedimentary rocks in the Central Burma Basin : implications for the evolution of the eastern Himalayan orogen and timing of large scale river capture." Thesis, University of St Andrews, 2015. http://hdl.handle.net/10023/6730.

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This study contributes to the understanding of major river evolution in Southeast Asia during the Cenozoic. In order to trace the evolution of a hypothesized palaeo-Yarlung Tsangpo-Irrawaddy River, this work undertakes the first systematic provenance study of detrital minerals from Cenozoic synorogenic fluvial and deltaic sedimentary rocks of the Central Burma Basin, employing a combination of high precision geochronology, thermochronology, and geochemistry analytical techniques on single grain detrital zircon and white mica. The dataset is compared to published isotopic data from potential source terranes in order to determine source provenance and exhumation history from source to sink. A Yarlung Tsangpo-Irrawaddy connection existed as far back as ca. 42 Ma and disconnection occurred at 18–20 Ma, based on provenance changes detected using a combination of U-Pb ages and εHf(t) values on detrital zircons, and ⁴ºAr/³⁹Ar dating on detrital micas. During the Eocene and Oligocene, units are dominated by U-Pb age and high positive εHf(t) values, characteristic of a southern Lhasa Gangdese magmatic arc source. An antecedent Yarlung Tsangpo-Irrawaddy River system formed the major river draining the eastern Himalaya at this time. A significant change in provenance is seen in the early Miocene, where detritus is predominantly derived from bedrock of the eastern Himalayan syntaxis, western Yunnan and Burma, a region drained by the modern Irrawaddy-Chindwin river system characterized by Cenozoic U-Pb ages and negative εHf(t) values. This is attributed to the disconnection of the Yarlung-Irrawaddy River and capture by the proto-Brahmaputra River, re-routing Tibetan Transhimalayan detritus to the eastern Himalayan foreland basin. Re-set zircon fission track ages of 14-8 Ma present in all units is used to infer post-depositional basin evolution related to changes in the stress regime accommodating the continued northward migration of India. The early Miocene initiation of the Jiali-Parlung-Gaoligong-Sagaing dextral shear zone and the continued northward movement of the coupled India-Burma plate aided in focusing deformation inside the syntaxis contributing to the disconnection of the Yarlung Tsangpo-Irrawaddy system, linking surface deformation and denudation with processes occurring at deeper crustal levels.

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"Sequence Stratigraphy of the Cenozoic Pannonian Basin, Hungary." Thesis, 1997. http://hdl.handle.net/1911/20480.

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The sequence stratigraphy of the middle Eocene-Pliocene of the Pannonian Basin permits to differentiate fifty-nine depositional sequences. An earlier compressional Paleogene basin in the central and eastern Pannonian Basin is unconformably overlain by a Neogene extensional basin. Tectonic regimes interacted with transgressive-regressive facies cycles. The boundaries of these cycles coincide with regional stage boundaries. Unconformities separating these cycles mark the episodic closure of connections between the Pannonian Basin and the European epicontinental seas from Oligocene through middle Miocene time. The unconformities are the result of short-term glacio-eustatic falls, sometimes enhanced by tectonic events. Within the limits of biostratigraphic resolution during the Eocene-middle Miocene, many of the sequences of the Pannonian Basin correlate well with the sequences proposed by Haq et al. (1987). However, eight sequences, i.e. one in the Lutetian, three in the Bartonian, one in the Priabonian, one in the Rupelian and two in the Burdigalian, were not identified by Haq et al. (1987). The sequences and their boundaries are directly correlated with global oxygen isotope events. Glacioeustasy generates sequence boundaries beginning as early as the middle Eocene. Within the lacustrine setting of the Pannonian Basin (late Miocene- Pliocene time) relative lake level changes appear to control the overall sequence development. However, other minor variables, the sediment supply and the topography of the initial depositional surface were additional controlling factors. Thus differences in the physiography of the basin lead to totally different sequence types that all reflect to lake level fluctuations. In lateral direction, during a short time period, these lacustrine sequences are more sensitive to changes in the initial depositional profile and sediment supply.
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31

Helgeson, James M. "Structure and stratigraphy of the Mountain Boy Range, Eureka County, Nevada." Thesis, 1993. http://hdl.handle.net/1957/35749.

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32

Marty, Richard Charles. "Stratigraphy and chemical sedimentology of Cenozoic biogenic sediments from the Pisco and Sechura Basins, Peru." Thesis, 1989. http://hdl.handle.net/1911/16267.

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Neogene sediments rich in siliceous microfossils, phosphate, and organic carbon formed simultaneously in many basins around the Pacific. This work focuses on these (and similar older) sediments from two basins of western South America (East Pisco and Sechura Basins) and studies the effects of tectonism, climate, and oceanic circulation on their formation. Transgressions inundated the East Pisco Basin during the late Eocene, late early Miocene, and late Miocene. Diatomaceous sediments formed during each transgression. Late Eocene diatomaceous sediments suggest that: upwelling off Peru dates from the late Eocene, a proto-Humboldt current existed during the Eocene, Antarctic cooling began before the latest Eocene, and the terminal Eocene event was the culmination of oceanic-climatic change. The late Eocene diatomites differ from overlying late Miocene sediments. Eocene diatomites are restricted to the western (offshore) margin of the basin, are separated from paralic sediments by a mud blanket, and were deposited well below wave base. Upper Miocene-Pliocene diatomites occur throughout the basin, grade into paralic deposits, and were deposited, in part, above storm wave base. The Sechura Basin experienced four transgressions between the Eocene and late Miocene. These transgressions formed four sedimentary sequences. Diatomaceous sediments are found in each sequence except the second (upper Oligocene-lower Miocene). In the third sequence (lower Zapallal Formation) diatomite-phosphorite became important between 14 and 8.1 Ma, and apparently reflects increased biogenic and decreased (?) terrigenous sedimentation rates. The increased biogenic accumulation rate reflects increased primary productivity or preservation. Sediments of the third sequence are separated from the fourth sequence by an angular unconformity (which correlates with subduction of the Nazca Ridge under the basin). Sediments of the fourth sequence differ from those of the third, and apparently record cooling and strengthened currents during the latest Miocene.

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Pollock, Rosalie Miranda. "Sequence stratigraphy of the Paleocene to Miocene Gambier Sub-basin, southern Australia / Rosalie M. Pollock." 2003. http://hdl.handle.net/2440/22021.

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Maps in pocket inside back cover.
Includes published papers and abstracts of works by the author
"November 2003"
Includes bibliographical references.
Various paging : ill. (chiefly col.), maps, plates, charts (some folded) ; 30 cm. + 2 scaled seismic survey maps
Title page, contents and abstract only. The complete thesis in print form is available from the University Library.
Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, National Centre for Petroleum Geology and Geophysics and Discipline of Geology and Geophysics, 2004

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Ferro, Carlos Elmer. "The Cenozoic tectonostratigraphic evolution of the Belize margin, the origin of the Belize barrier reef, and sequence stratigraphy of the late Quaternary mixed siliciclastic-carbonate system." Thesis, 2001. http://hdl.handle.net/1911/17961.

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The primary objectives of this study were to understand the origin of the Belize Barrier Reef and the sequence stratigraphy of the mixed siliciclastic-carbonate system. The data used consisted of 1,400 km of conventional multichannel seismic, 1,300 km of single-channel high resolution seismic, and information from nine wells. Conventional seismic shows elongated NNE-SSW highs and lows (Camels Basin, Camels Hump-Turneffe atoll, Gladden Basin, Glovers atoll-Lighthouse Island). The thrusted block of Camels Hump formed from buttressing of the Maya Mountains against the moving Caribbean plate during the Paleocene. Its load generated Camels Basin, whereas Gladden and Turneffe Basins formed as pull-aparts. The transtension produced the Turneffe and the Glovers-Lighthouse alignments whose tops as well as Camels Hump's were covered by carbonate platforms during the late Eocene/Oligocene. These carbonates were partially drowned in the early/middle Miocene. During the middle/late Miocene, tectonic enhancement of Camels Hump and Glovers highs triggered the collapse of their margins, shedding mass flow deposits. The late Pliocene/early Pleistocene sea-level fall moved the shoreline along the eastern flank of Camels Hump and in the northern Camels Basin where longshore currents redistributed the sediments. The Belize Barrier Reef became established on top of these lowstand siliciclastic coastal deposits in the middle of the Brunhes Epoch (about 0.45 Ma). Once the barrier reef was formed, it established the modern mixed siliciclastic-carbonate system. When sea-level dropped, about 120 m during the Last Glacial Maximum (18,000 years ago), the reef built during the previous interglacial highstand was karstified. The shelf lagoon became a fluvial plain drained by two incised valley systems. The northern fluvial system deposited a lowstand delta at the mouth of the English Cay Channel. This delta was partially reworked by longshore currents. The rise of sea-level slowed at about -65 to -70 m, 11,000 to 10,000 years ago (Younger Dryas) and is documented by a landward-stepped delta. As sea-level rise resumed, the incised valleys became filled with fluvial to estuarine sediments and, then, buried under marine marls. Flooding at about 7,000 years ago reactivated the reef.

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Verdel, Charles Steven. "I. Cenozoic Geology of Iran: An Integrated Study of Extensional Tectonics and Related Vulcanism. II. Ediacaran Stratigraphy of the North American Cordillera: New Observations from Eastern California and Northern Utah." Thesis, 2009. https://thesis.library.caltech.edu/3631/7/Verdel_thesis.pdf.

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I. The late Oligocene to Miocene collision of Arabia and Eurasia was preceded by ~175 My of subduction of Neotethyan oceanic crust. Associated magmatic activity includes late Triassic(?) to Jurassic plutons in the Sanandaj-Sirjan zone of southern Iran, limited Cretaceous magmatism in the Alborz Mountains of northern Iran, and widespread Eocene volcanism across central Iran. Metamorphic core complexes of Eocene age have recently been recognized in widely separated parts of Iran, suggesting that Tertiary volcanism was related to extension. Geochemical data indicate that Eocene volcanism was typical of continental arcs and was followed by less voluminous Oligocene basaltic volcanism of the type often associated with back-arc basins. This set of observations suggests that mid-Mesozoic plutons in southern Iran are the remnants of an original volcanic arc that was only weakly developed because of slow subduction rate. Magmatic activity largely ceased in southern and central Iran during the Cretaceous and shifted to the north, suggesting a period of flat slab subduction. Subsequent slab-rollback during the Eocene extended the overriding plate, forming metamorphic core complexes and inducing pressure-release melting of partially hydrated lithospheric mantle and upwelling of asthenosphere.

II. The Ediacaran Period spans from the base of cap carbonates overlying glacial deposits of the Marinoan “Snowball Earth” event to the Precambrian-Cambrian boundary, ~635 to 542 Ma. Sediments deposited during the rifting of southwest Laurentia, which are now exposed in a relatively narrow belt in the western US, are one of the best records on earth of the geological, geochemical, and geobiological events that occurred during this period. Evidence for one of the most significant of these, the final oxygenation of the oceans, is found within the upper Johnnie Formation in the southern Great Basin. C isotope data from thick, basinal facies of the Johnnie Fm. in the Panamint Range provide a more complete record of ocean chemistry associated with this event than previously determined from thinner, platformal facies. Strata in northern Utah of roughly the same age include a rift-related basalt, providing some of the youngest geologic evidence for the rifting of western Laurentia.

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McIntyre, Jana L. "Late Cenozoic structure of the central Wassuk Range, Mineral County, Nevada /." 1990. http://hdl.handle.net/1957/12257.

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Thesis (M.S.)--Oregon State University, 1990.
Includes plates in pocket. Includes mounted photographs. Typescript (photocopy). Includes bibliographical references (leaves 89-92). Also available on the World Wide Web.

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Castillo, María Verónica. "Structural analysis of Cenozoic fault systems using 3D seismic data in the Southern Maracaibo Basin, Venezuela /." 2001. http://www.lib.umi.com/cr/utexas/fullcit?p3036164.

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Zaprowski, Brent Jason. "The geomorphic evolution of the Black Hills of South Dakota and adjacent High Plains during the late Cenozoic : knickzone propagation." Diss., 2001. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3010438.

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Puchner, Richard A. "The geology and rock mass quality of the Cenozoic Kalahari Group, Nchwaning Mine Northern Cape." Thesis, 2002. http://hdl.handle.net/10413/4108.

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With the extension of the Nchwaning Mine shaft complex in the Northern Cape Province, various geological and geotechnical complications needed to be identified in order to ensure correct use of tunnelling methods and support techniques. An understanding of the geological history of the area and the resulting geotechnical nature was important in defining the rock mass quality ahead of shaft development. A total of 12 geotechnical boreholes were drilled, and an additional 18 old boreholes revisited to accurately detennine the stratigraphy, geological structure and associated weathering effects. Various soils and rock testing helped quantify the materials encountered. Sands of the Gordonia Fonnation form the surface cover of this area, and together with the weathered calcrete, calc-arenite, conglomerate and clay, they form part of the Cenozoic Kalahari Group. The 30m thick basal unit of red clay is common throughout this region. This silty clay material is problematic in that it is expansive and hygroscopic. The clay unit rests unconformably on folded, faulted and highly weathered shale of the Proterozoic Lucknow and Mapedi Formations of the Olifantshoek Supergroup. Unconformably below this sequence lies the manganiferous ore deposits of the Hotazel Member, which is contained within the Voelwater Formation of the Griqualand West Supergroup. For the development of the decline shaft through the Gordonia Formation a box cut was excavated to a depth of 25m. The anticipated poor geotechnical conditions for a further 125m below the Gordonia sands called for high quality permanent tunnel support in the upper weathered horizons. Barton's Q-analysis was adopted as a recognized tunnelling quality index to predict and quantify the rock mass characteristics ahead of the shaft. The highly variable and generally low Q-values from borehole core analysis indicated that precast tunnel lining be used for 800m (at 11.5°) through the entire weathered Cenozoic sequence and into the weathered shales immediately below the Red Clay.
Thesis (M.Sc.)-University of Natal, Durban, 2002.

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Dissertations / Theses on the topic 'Stratigraphy geology - Cenozoic'

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