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Dissertations / Theses on the topic 'Th dating'

Author: Grafiati

Published: 1 April 2023

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1

Loehn, Clayton William. "Investigation of the monazite chemical dating technique." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/27688.

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In order to evaluate the electron microprobe (EMP) method for chemical dating of monazite, we chemically analyzed selected suites of monazite grains that were previously dated by standard U/Pb isotopic methods at three laboratories each equipped with a sensitive high resolution ion microprobe (SHRIMP). Representing diverse igneous and metamorphic lithologies, these grains yielded conventional isotopic ages ranging in age from Neoarchean to Devonian. Chemical dating was performed at Virginia Tech using a Cameca SX-50 EMP in which the analytical routines and settings were specifically optimized

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2

Simons, Suzanne Lee. "U-Th-Pb systematics of opaline silica: Implications for the dating of surface processes." Thesis, Curtin University, 2015. http://hdl.handle.net/20.500.11937/36.

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U–Pb and U-series analyses of U-rich, relative to both Th and Pb, opal samples using sensitive high-resolution ion microprobe (SHRIMP) demonstrate the ability of this technique for dating opals with ages ranging from several tens of thousands of years to millions of years and from a variety of deposition environments. This experimental study increases the understanding of opal as a geochronometer and explores the stability of U-Th-Pb systematics in opaline silica.

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Placzek, Christa. "Stratigraphy, Geochronology and Geochemistry of Paleolakes on the Southern Bolivian Altiplano." Diss., The University of Arizona, 2005. http://hdl.handle.net/10150/194352.

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Precise chronologies of climate events in the tropics are rare yet essential for understanding how tropical climate relates to global climate at millennial to longer time scales. An increasingly important area for understanding these interactions is the southern Bolivian Altiplano (15-22oS) which represents the waning and southeastern end of the South American Monsoon, a system that is, today, modulated by regional upper-air circulation anomalies under the influence of tropical Pacific sea-surface temperature gradients associated with El NiÃ±o/Southern Oscillation (ENSO). Mechanisms of summ

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4

Guenthner, William Rexford. "Zircon (U-Th)/He Dates from Radiation Damaged Crystals: A New Damage-He Diffusivity Model for the Zircon (U-Th)/He Thermochronometer." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/306783.

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Zircon (U-Th)/He (zircon He) dating has become a widely used thermochronologic method in the geosciences. Practitioners have traditionally interpreted (U-Th)/He dates from zircons across a broad spectrum of chemical compositions with a single set of ⁴He diffusion kinetics derived from only a handful of crystals (Reiners et al., 2004). However, it has become increasingly clear that a "one-size-fits-all" approach to these kinetics is inadequate, leading to erroneous conclusions and incongruent data. This dissertation develops a more grain-specific approach by showing the fundamental role that in

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Burnside, Neil Murray. "U-Th dating of travertines on the Colorado Plateau : implications for the leakage of geologically stored CO2." Thesis, University of Glasgow, 2010. http://theses.gla.ac.uk/1988/.

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In order to avoid the damaging climatic consequences of rising atmospheric CO2, and reduce current atmospheric CO2 concentrations to pre-industrial levels, anthropogenic CO2 emissions must be mitigated by capturing CO2 at power plants and storing it for thousands of years. Underground storage within deep geological formations, such as depleted gas and oil fields or deep saline aquifers, is the best understood solution for storage of CO2. In order for this method to gain more public and political acceptance it is important to characterise the potential causes, quantities and rates of CO2 releas

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6

Dean, J. R. "Stable isotope analysis and U-Th dating of late glacial and Holocene lacustrine sediments from central Turkey." Thesis, University of Nottingham, 2014. http://eprints.nottingham.ac.uk/14090/.

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Water is a politically sensitive resource in the Near East and water stress is increasing. It is therefore vital that there is a strong understanding of past hydrological variability, so that the drivers of change can be better understood, and so that the links between the palaeoclimate and archaeological records in this key region in the development of human civilisation can be investigated. To be of most use, this requires high resolution records and a good understanding of palaeoseasonality. A sediment sequence spanning ~14,000 years has been retrieved from Nar Gölü, a lake in central Turke

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Yamada, Kunimi. "Thermochronology using (U-Th)/He dating method : investigation for effects of secular disequilibrium on (U-Th)/He ages and uplift history of the Tanzawa mountains in the south Fossa Magna region." 京都大学 (Kyoto University), 2006. http://hdl.handle.net/2433/144205.

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Kyoto University (京都大学)<br>0048<br>新制・課程博士<br>博士(理学)<br>甲第12122号<br>理博第3016号<br>新制||理||1450(附属図書館)<br>23958<br>UT51-2006-J117<br>京都大学大学院理学研究科地球惑星科学専攻<br>(主査)助教授田上高広, 教授嶋本利彦, 教授小畑正明<br>学位規則第4条第1項該当

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8

Xia, Qikai. "High precision TIMS U-Th disequilibrium dating and C, O, Sr isotope-based multi-proxy palaeoclimatic study of Speleothems in Australia /." [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18421.pdf.

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9

Adams, Byron A. "Exhumation and incision history of the Lahul Himalaya, northern India, based on (U-Th)/He thermochronometry and terrestrial cosmogenic nuclide dating techniques." Cincinnati, Ohio : University of Cincinnati, 2007. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1180546920.

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Thesis (M.S.)--University of Cincinnati, 2007.<br>Title from electronic thesis title page (viewed Oct. 8, 2007). Includes abstract. Keywords: Lahul, Himalaya, exhumation, incision, thermochronometry, terrestrial cosmogenic nuclides, strath terraces. Includes bibliographical references.

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10

Brown, Summer Jasmine. "Integrating apatite (U-Th)/He and fission track dating for a comprehensive thermochronological analysis: refining the uplift history of the Teton Range." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/32718.

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Uplift of the Teton Range is primarily controlled by displacement across the range-front Teton normal fault. The Tetons comprise the footwall block while the hanging wall encompasses Jackson Hole valley and a portion of the Snake River. Relative to the rest of the Rocky Mountains, the Tetons experienced the majority of uplift very recently, substantiating the need for a detailed investigation integrating structural analysis and bedrock thermochronometry. New low-temperature cooling ages are documented in three vertical transects across the Teton Range and at low elevations parallel to the T

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Adams, Byron A. "Exhumation and incision histories of the Lahul Himalaya, northern India, based on (U-Th)/He thermochronology and terrestrial cosmogenic nuclide dating techniques." University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1180546920.

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12

Buscher, Jamie Todd. "Long-term exhumation of landscapes along the Pacific-North American plate boundary as inferred from apatite (U-Th)/He and ArcGIS analyses." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/27760.

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The Pacific-North American plate boundary is typified by transpression and convergence, yet the relationship between interplate deformation and long-term crustal shortening is not fully understood. The continuous belt of rugged topography that extends along the entire plate boundary is generally associated with oblique tectonic plate motion, strong interplate coupling, and terrane accretion, but relating plate boundary orogenesis to variations in plate geometry and behavior requires detailed case studies. The northern San Gabriel Mountains along the San Andreas fault and the Chugach-Kenai Moun

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Sakata, Shuhei. "Development of analytical technique for precise age determination of Quaternary zircons with the correction of the initial disequilibrium on U-Th-Pb decay series using a laser ablation-ICP-mass spectrometry." 京都大学 (Kyoto University), 2015. http://hdl.handle.net/2433/199112.

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Kawata, Marcelo Takei. "Evolução tectono-metamórfica da formação São Tomé, Grupo Rio Doce, faixa Araçuaí." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/44/44141/tde-17072018-144805/.

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A presente dissertação apresenta uma investigação sobre a evolução tectono-metamórfica da Formação São Tomé, uma das unidades metassedimentares pertencente ao Grupo Rio Doce, no Orógeno Araçuaí. Essa unidade, de origem pelítica, ocorre em uma faixa com direção geral aproximadamente N-S, com vergência para NE, contrária ao cráton São Francisco neste setor do orógeno. Possui como litotipo principal quartzo-mica xisto, com proporções variadas de granada, estaurolita, sillimanita e plagioclásio. Duas fases deformacionais estão registradas através de uma foliação continua S1 do tipo clivagem de fra

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15

Marsden, Ruby Connemara. "Further Development and Testing of the Combined U-Thdisequilibrium/ U-Pb and (U-Th)/He Zircon Dating Method and its Application to Quaternary Volcanic Rocks." Thesis, Curtin University, 2021. http://hdl.handle.net/20.500.11937/88743.

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Volcanic eruptions that are <1 Ma are significant for geological and archaeological investigations, however these eruptions can be challenging to date. Zircon double-dating (ZDD) is one of the few techniques that can be used to date young volcanic rocks, and combines the (U-Th)/He method with individual zircon crystallisation ages to yield eruption ages. This thesis presents several methodological improvements to the ZDD methodology and applies it to two case studies.

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16

Savignano, Elisa. "Apatite (U-Th)/He and Fission Track thermochronometry in the Northern Patagonian Andes: New insights into the exhumation history of the thrust belt foreland sector." Doctoral thesis, Università degli studi di Padova, 2018. http://hdl.handle.net/11577/3421962.

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The study of the Cretaceous–Cenozoic evolution of the North Patagonian Andes represents a great opportunity to investigate the effects of coupling between deep lithospheric processes and near-surface deformation. Despite the general along-strike continuity, this mountain belt is characterized by a pronounced internal tectonic segmentation (marked by the variable position of the magmatic arc and of the deformation front to the east). Thus, this plate margin results in a more complex conﬁguration with respect to the simpliﬁed notion of “Andean-type” subduction system. Being located in the retro

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Airaghi, Laura. "Etude pétro-chronologique de la chaîne des Longmen Shan (Tibet oriental) : héritage géologique et implications pour la géodynamique actuelle." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAU029/document.

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Un des enjeux majeurs en Sciences de la Terre est la compréhension des mécanismes de déformation de la lithosphère continentale dans des zones de convergence. Le plateau Tibétain constitue un laboratoire naturel idéal pour l'étude des processus crustaux profonds actifs dans ces contextes, du fait de sa superficie et de son altitude remarquables. Le soulèvement et l'épaississement de la croûte Tibétaine ont été classiquement attribués aux effets de la collision Inde-Asie Tertiaire. Cependant, cette interprétation a été récemment mise en question par une série d’observations géologiques et géoph

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Finné, Martin. "Climate in the eastern Mediterranean during the Holocene and beyond – A Peloponnesian perspective." Doctoral thesis, Stockholms universitet, Institutionen för naturgeografi och kvartärgeologi (INK), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-108046.

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This thesis contributes increased knowledge about climate variability during the late Quaternary in the eastern Mediterranean. Results from a paleoclimate review reveal that regional wetter conditions from 6000 to 5400 years BP were replaced by a less wet period from 5400 to 4600 years BP and to fully arid conditions around 4600 years BP. The data available, however, show that there is not enough evidence to support the notion of a widespread climate event with rapidly drying conditions in the region around 4200 years ago. The review further highlights the lack of paleoclimate data from the ar

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Cros, Alexandre. "Influence des propriétés cristallochimiques de la calcite sur la diffusion de l'hélium et essai de datation (U-Th-Sm)/He de calcite filonienne et de remplissage de brèche." Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00719709.

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La datation des carbonates est un enjeu important en géosciences car ces minéraux sont présents dans tous les grands cycles superficiels terrestres. Actuellement, l'âge de formation des cristaux de calcite de failles peut être déterminé par la méthode de déséquilibre U-Th ou par la méthode U-Pb. La potentialité de la méthode (U-Th-Sm)/He a été envisagée à partir des premiers résultats de diffusion de l'hélium dans les carbonates (Copeland et al. 2007) qui montrent que l'hélium est rétentif à basse température, inférieure à 70°C. Le développement de cette méthode nécessite une identification de

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CRUZ, ROSANA PETINATTI DA. "DEVELOPMENT OF A METHODOLOGY FOR CORALS AND SPELEOTHEMS DATING USING THE 230-TH/234-U METHOD, THROUGH CHROMATOGRAPHIC SEPARATION AND QUANTIFICATION BY ALPHA SPECTROMETRY AND FIA-ICP-MS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2006. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=8544@1.

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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO<br>O presente trabalho aborda as determinações de idades de espeleotemas e corais, usando o método de desequilíbrio da série urânio, mais especificamente, o método de deficiência de filhos daughter deficient DD, em particular o método 230Th/234U. Foram testadas diferentes metodologias empregando separação por extração cromatográfica e quantificação por espectrometria alfa e ICP-MS. Foram testados três procedimentos diferentes: separação em batelada empregando-se colunas com Tri-octil óxido de fosfina (TOPO) em silica- gel

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21

Didier, Amélie. "Comportement géochimique du chronomètre U-Th-Pb dans la monazite : approche par analyses in-situ au LA-ICP-MS." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2013. http://tel.archives-ouvertes.fr/tel-00966588.

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La richesse en Th et en U de la monazite en fait un excellent géochronomètre pour dater les roches magmatiques et métamorphiques de la croûte terrestre. Peu sensible à la diffusion du Pb dans sa structure cristalline, elle peut enregistrer des évènements géologiques de haute température sans risque de remise à zéro de son géochronomètre. Réservoir principal des actinides et des lanthanides, elle participe à de nombreuses réactions minéralogiques, faisant aussi d'elle un très bon traceur pétrogénétique. Coupler sa chimie à son isotopie permet donc d'interpréter précisément la nature des process

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Oostingh, Kornelia Fieneke. "Ultra-Precise 40Ar/39Ar Geochronology: Development of 38Ar cosmogenic exposure and olivine (U-Th)/He dating techniques; and deciphering the geochemical evolution of the Newer Volcanic Province, SE Australia." Thesis, Curtin University, 2017. http://hdl.handle.net/20.500.11937/53004.

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In this study, existing (40Ar/39Ar) and underdeveloped (terrestrial cosmogenic 38Ar exposure dating and olivine (U-Th)/He dating) geochronology techniques are used and improved to better understand the igneous geology and landscape evolution of Australia. It is shown that an integral approach of geochemistry and ultra-precise geochronology, using the new generation multi-collector mass spectrometers, is of paramount importance to decipher the volcanic history of the small, intraplate Newer Volcanic Province in SE Australia.

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Berger, Aaron Louis. "A Thermochronological Investigation of Orogenic Architecture, Kinematics, and Tectonic-Climatic Interactions within the St. Elias Orogen, Alaska." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/26628.

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The kinematics and architecture of orogenic systems may be heavily influenced by climate, but little research has focused on the long-term effects of glacial erosion on orogenesis. Low-temperature thermochronometry and subsidiary structural, earthquake relocation, and offshore seismic reflection data from the St. Elias orogen are the basis for a new architectural model and demonstrate an association between glacial denudation and orogenic evolution. These data show that exhumation and deformation within the St. Elias orogen are focused across a thin-skinned fold and thrust belt on the windward

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Boyd, Meighan. "Speleothems from Warm Climates : Holocene Records from the Caribbean and Mediterranean Regions." Doctoral thesis, Stockholms universitet, Institutionen för naturgeografi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-121750.

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This thesis contributes to increased knowledge on Holocene climate and environmental variability from two complex and sparsely studied areas. Using a speleothem from Gasparee Cave, Trinidad, as a paleoclimate archive, the local expression of the 8.2 ka (thousand years before 1950) climate event and associated patterns of the inter-tropical convergence zone (ITCZ) and rainfall is provided. Subsequent speleothem studies using multi-proxy analysis of stalagmites from Kapsia Cave and Alepotrypa Cave, Greece, provide records of climate, vegetation and human induced changes in the cave environment d

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Oliveira, Raphael Logato de. "Esclerocronologia, geoquímica e registro climático em coral Siderastrea stellata do Atol das Rocas, RN, Brasil." Niterói, 2017. https://appdesenv.uff.br/riuff/handle/1/4454.

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Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2017-09-11T18:18:13Z No. of bitstreams: 1 diss-Raphael-Logato-de-Oliveira-PPGA.pdf: 25249109 bytes, checksum: bebdeef5c344d7c319f3fd7481af2cce (MD5)<br>Made available in DSpace on 2017-09-11T18:18:13Z (GMT). No. of bitstreams: 1 diss-Raphael-Logato-de-Oliveira-PPGA.pdf: 25249109 bytes, checksum: bebdeef5c344d7c319f3fd7481af2cce (MD5)<br>Conselho Nacional de Desenvolvimento Científico e Tecnológico<br>Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geoquímica, Niterói, RJ<br>A taxa

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Feneyrol, Julien. "Pétrologie, géochimie et genèse des gisements de tsavorite associés aux gneiss et roches calco-silicatées graphiteux de Lemshuku et Namalulu, Tanzanie." Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0348/document.

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La tsavorite, grossulaire vert à V-Cr-Mn, est contenue dans des gneiss et roches calco-silicatées graphiteux, souvent associés à des marbres dolomitiques, et appartenant à la ceinture métamorphique néoprotérozoïque mozambicaine. La tsavorite se trouve soit dans des nodules ou des veines de quartz (gisements primaires), soit dans des placers (gisements secondaires). L'étude minéralogique des tsavorites propose un nouveau protocole de certification de leur origine géographique, à partir du rapport V/Cr, de la teneur en Mn et du [delta]18 O. L'étude des gisements de Lemshuku et Namalulu en Tanzan

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El, Bakili Asmae. "Evolution tectono-metamorphique et chronologique des unités métamorphiques du Rif interne (Beni Bousera, Nord du Maroc)." Thesis, Université Côte d'Azur, 2021. http://www.theses.fr/2021COAZ4034.

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Située à l'extrême-ouest de la Méditerranée occidentale, la chaîne bético-rifaine s’est formée au travers d’une histoire orogénique alpine complexe, impliquant des processus de subduction liés à la convergence entre l’Afrique et l’Eurasie depuis le Crétacé. Une découverte importante de ces quatre dernières décennies d'investigations géologiques, a été la mise en évidence des vestiges d’un événement varisque dans les zones internes de la chaîne. Ces résultats soulignent bien la présence de deux systèmes orogéniques superposés, les zones internes de la chaîne bético-rifaine demeurent donc des zo

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Ternois, Sébastien. "Reconstruction de la Dynamique Précoce d'un Orogène : Mise en évidence de la Transition Rifting-Collision dans le système est-pyrénéen (France) par la Géo-thermochronologie." Thesis, Université de Lorraine, 2019. http://www.theses.fr/2019LORR0086/document.

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Les orogènes collisionnels sont classiquement décrits comme le résultat de l'accrétion continentale de marges proximales. Cette accrétion conduit à la surrection des reliefs et à l'export important de produits d'érosion dans les bassins d'avant-pays qui les jalonnent. Dans ce schéma géodynamique sont alors uniquement considérés les domaines pré-orogéniques les moins déformés. Pourtant, un nombre croissant d'évidences géologiques de terrain indiquent la conservation voire la réutilisation de structures héritées de la phase extensive précédant la convergence et la collision au coeur des orogènes

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Gregory, Courtney Jayne. "Allanite chemistry and the U-Th-Pb geochronology." Phd thesis, 2009. http://hdl.handle.net/1885/151732.

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"(U-Th)/He, U/Pb, and Radiation Damage Dating of the Rochechouart-Chassenon Impact Structure, France." Master's thesis, 2016. http://hdl.handle.net/2286/R.I.40296.

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abstract: It has been hypothesized that the ~25 km Rochechouart-Chassenon impact structure (RCIS) in the NW Massif Central, France, was formed during a Late Triassic (ca. 214 Ma) terrestrial impact event that produced a catena of several large craters. Testing this hypothesis, and assessing its possible impacts on biological evolution, requires both accurate and precise dating of candidate impact structures. Like many of these structures, the age of the RCIS is controversial because geochronological datasets yield contradictory results, even when a single isotopic system is used; for example,

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Bo-RenWang and 王伯仁. "Behavior of U and Th isotopes in diagenetically-altered fossil corals: its implication for U-series dating." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/57774961542072695743.

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碩士<br>國立成功大學<br>地球科學系碩博士班<br>98<br>To understand the behavior of uranium-series isotopes in diagenetically-altered fossil corals, this study collected fossil corals from Kenting, Heng Chun Peninsula, Taiwan. After separating each coral sample into 3-5 sub-coral samples, we measured the distributions of uranium (238U, 234U) and thorium (230Th, 232Th) isotopes in each of these subsamples. Results show that the modern and unaltered corals collected from Eruanbi (鵝鑾鼻) at modern sea-level have 238U activities 2.28 ± 0.08 dpm/g in consistence with those of unaltered corals reported previously for ot

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Chapman, Shay Michael. "Thermal and Structural Constraints on the Tectonic Evolution of the Idaho-Wyoming-Utah Thrust Belt." Thesis, 2013. http://hdl.handle.net/1969.1/151236.

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The timing of motion on thrust faults in the Idaho-Wyoming-Utah (IWU) thrust belt comes from synorogenic sediments, apatite thermochronology and direct dating of fault rocks coupled with good geometrical constraints of the subsurface structure. The thermal history comes from the analyses of apatite thermochronology, thermal maturation of hydrocarbon source rocks and isotope analysis of fluid inclusions from syntectonic veins. New information from zircon fission track and zircon (U-Th)/He analysis provide constraints on the thermal evolution of the IWU thrust belt over geological time. These an

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Bense, Frithjof A. "Multi-Method Chronometric Constraints on the Thermal, Structural and Morphotectonic Evolution of the Eastern and Western Sierras Pampeanas with Special Emphasis on K-Ar Dating of Fault Gouges." Doctoral thesis, 2013. http://hdl.handle.net/11858/00-1735-0000-0001-BB21-8.

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Die hier präsentierte Studie umfasst detaillierte Untersuchungen zur thermochronologischen, strukturellen sowie morphologischen Entwicklung der Östlichen und Westlichen Sierras Pampeanas in Argentinien, zwischen 26°S to 34°S südlicher Breite. Kapitel 3 diskutiert thermochronologische Daten (Apatit Spaltspuren, Zirkon und Apatit (U-Th)/He) sowie K-Ar Illit-Datierung an Störungsletten aus der Sierra de Comechingones sowie Ar-Ar Alter an Vulkaniten des vulkanischen Gürtels von San Luis (Östliche Sierras Pampeanas). K-Ar Illitalter belegen den Beginn spröder Deformation vor etwa 340 Ma. Thermochro

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"Tools, Techniques, and Applications For Detrital Thermochronology: From the Lab to the Eastern Sierra Nevada, California." Doctoral diss., 2019. http://hdl.handle.net/2286/R.I.54811.

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abstract: Geochronology and thermochronology are valuable tools for investigating the synergy between the deformational and erosional processes that shape mountainous terrains. Though numerous techniques have been developed to probe the rate and timing of events within these settings, the research presented here explores how scientists can use fewer samples to produce richer data products with broader contextual importance. The beginning of this compilation focuses on establishing laboratory techniques to facilitate this goal. I developed a novel laser ablation ‘double dating’ (LADD) techniqu

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Fanta, Martin. "Datování vývěrů radioaktivních minerálních vod v krkonošsko-jizerském krystaliniku metodou 230Th/234U." Master's thesis, 2016. http://www.nusl.cz/ntk/nusl-349028.

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The isotopes 238 U, 234 U and 230 Th, as members of the uranium-radium decay chain, are fractionated in the environment by changes of geochemical conditions, and they can be used for dating of recent or past geochemical processes in the Quaternary. Samples of water with uranium and of water-activated solids were taken of radioactive mineral water springs at two study sites in the area of Krkonoše-Jizera crystalline complex: Svatý Vojtěch (St. Adalbert) in Horní Malá Úpa, and Bukový Pramen in the Těsný důl valley in Janské Lázně. Uranium was co-precipitated in field conditions with hydroxides o

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Makhubela, Tebogo Vincent. "⁴⁰ Ar/³⁹Ar and (U-Th)/He dating attempts on the fossil-bearing cave deposits of the Malapa and Sterkfontein hominin sites of the Cradle of Humankind, South Africa." Thesis, 2015. http://hdl.handle.net/10210/13697.

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M.Sc. (Geology)<br>The Cradle of Humankind is a 47 000 hectare demarcated area with over three dozen fossil-bearing cave sites well known for the preservation of fossil evidence of early hominin taxa such as Australopithecus Africanus, Australopithecus Sediba, Paranthropus Robustus and Early Homo. As a result, a database of precise and accurate chronological data for fossil-bearing cave deposits of the Cradle of Humankind (similar to that for East African fossil sites) is very important, but developing one has proven extremely challenging. The main challenge is that the fossil-bearing deposits

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Haider, Viktoria L. "Evolution and decay of peneplains in the northern Lhasa terrane, Tibetan Plateau." Doctoral thesis, 2014. http://hdl.handle.net/11858/00-1735-0000-0023-990C-4.

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Diese Dissertation befasst sich mit der Entwicklung von “Fastebenen”, die im Weiteren einheitlich als “Peneplains” bezeichnet werden, sowie dem Zerfall dieses markanten geomorphologischen Erscheinungsbildes im südlichsten Teil des tibetischen Plateau dem sogenannten Lhasa Block. Im Zuge dieser Arbeit konnten neue Erkenntnisse über die Hebungsgeschichte und der Sedimentverteilung in diesem Untersuchungsgebiet gewonnen werden. Diese Ergebnisse tragen zu einem besseren Verständnis der geodynamischen Entwicklung Asiens bei, die bis heute viele Fragen aufwirft. Ende des 19. Jahrhunderts wurden Pene

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