Resumo: Foram usados estudos de mobilidade de elementos geoquímicos, isotópicos e petrológicos para investigar o comportamento dos isótopos radiogênicos Rb/Sr, Sm/Nd e U/Pb na formação de, migmatitos estromáticos e diatexiticos em três ambientes geotectônicos distintos. Os estudos foram realizados em migmatitos derivados de rochas metassedimentares do Grupo Seridó que teve deposição e metamorfismo no Neopreterozóico, em ortognaisses migmatíticos de composição granítica e tonalítica do Complexo Caicó de idade Paleoproterozóica e em ortognaisses migmatíticos de composição tonalítica do Complexo Presidente Juscelino no Maciço São José de Campestre de idade Arqueana. Os resultados nos micaxistos do Grupo Seridó mostraram que os leucossomas foram gerados por exsudações de quartzo e feldspatos formados a partir dos elementos Na, Ca e Si liberados do paleossoma pela fusão parcial que se individualizaram como veios. O Rb permaneceu imóvel no sistema e Sr perdeu massa, enquanto Sm e Nd permaneceram imóveis. As sistemáticas isotópicas Rb/Sr e Sm/Nd foram fortemente afetadas durante o processo de migmatização, fornecendo idades sem significado geológico. / Abstract: Studies of chemical elements mobility, isotopics and petrologic were used to investigate the behavior of the radiogenic isotope Rb/Sr, Sm/Nd and U/Pb in the formation of, estromatics migmatites and diatexites in three different tectonic setting. The studies were accomplished in derived migmatites of metasedimentary rocks of the Seridó Grup Seridó that had deposition and metamorphism in Neopreterozóico, in migmatitics orthogneisses of granitic and tonalitic composition of the Caicó Complex of Paleoproterozoic age and in migmatitics orthogneisses of tonalitic composition of the President Juscelino Complex in São José de Campestre Massif of Archaean age. The results in mica-schist's Seridó Grup showed that the leucosome was generated by exsudation of quartz and feldspars formed starting from the elements In the Ca and Si liberated of the paleosome for the melting partial that were individualized as veins. The Rb stayed immobile in the system and Sr lost mass, while Sm and Nd stayed immobile. The isotopics systematics Rb/Sr and Sm/Nd were strongly affected during the process migmatization, supplying ages without geological meaning. / Orientador: Jean Michel Legrand / Coorientador: Elton Luiz Dantas / Banca: Luiz Sérgio Amarante Simões / Banca: Antenor Zanardo / Banca: Jaziel Martin Sá / Banca: Elson Paiva Oliveira / Doutor

abstract: This research focuses upon the intersection of social complexity and leadership among commoners in complex societies as expressed through mortuary ritual. I study how ideology, materialized through treatment of the deceased body, was a potential source of power among commoners in ancient Maya society and how this materialization changed through time. Mortuary data are drawn from mid-level settlements of the Belize River Valley, located in western Belize within the eastern Maya lowlands. The primary research question addresses whether mid-level leaders in the Belize River Valley targeted certain human bodies for ancestral veneration through tomb re-entry and ritual interaction with skeletal remains. The ritual-political strategy of mid-level leaders is measured using archaeothanatology, an analysis of grave taphonomy based on forensic data, to reconstruct cultural beliefs about death based on treatment of deceased bodies, radiogenic strontium isotope analysis to reconstruct residential history, and analysis of dental metrics to assess biological kinship. While preservation of osseous material was poor, results indicate that the frequency of disarticulated and secondary burials was higher in eastern structures than in other locales, although eastern structures were not the only loci of these types of deposits. Overall, it does not seem like secondary burials were regularly and purposefully created for use as ritual objects or display. Radiogenic strontium isotope data enrich this analysis by showing that eastern structures were not a burial locale exclusive to individuals who spent their childhood in the Belize Valley. Data from upper-level eastern structures also suggests that within that part of society local birth did not guarantee interment in a local manner; perhaps the social network created during one's life shaped treatment in death more than residential origin. Biological distance analyses were inconclusive due to missing data. Comparison of mortuary practices to nearby regions shows distinct mortuary patterning across space and time. This is consistent with reconstructions of ancient Maya sociopolitical organization as regionally diverse and moderately integrated. / Dissertation/Thesis / Doctoral Dissertation Anthropology 2015

Les flux d'eau douce, glace de mer et courants océaniques, de l'Océan Arctique vers les mers nordiques jouent un rôle critique sur l'Atlantic Meridional Overturning Circulation et donc sur le système climatique. Les facteurs contrôlant ces flux sont encore partiellement méconnus. Un moyen indirect de retracer l'intensité et les schémas de circulation de la glace de mer est de retracer l'origine des sédiments qu'elle transporte, et qui sédimentent le long des grands courants de glace et d'eau douce vers l'Atlantique Nord. Il s'agit donc de tracer un flux particulaire direct, lié à la matrice des particules détritiques. Un second flux, indirect, provient des éléments dissous dans les masses d'eau, marqués par les processus d'adsorption/désorption le long des marges où les flux particulaires terrigènes sont les plus importants. L'extraction de la phase authigène d'un signal dissous par lessivage spécifique, a permis de documenter l'évolution des masses d'eau transitant par le détroit de Fram. Les données isotopiques de Pb, Nd et Sr nous ont permis d'identifier deux sources principales de sédiments depuis le dernier maximum glaciaire jusqu'au Dryas Récent : les marges canadiennes et russes alors recouvertes par des calottes de glace. Après le Dryas Récent, les sources sédimentaires sont plus diverses avec notamment une contribution des marges groenlandaises et des mers de Chukchi et Est Sibérienne. La fraction authigène montre un changement entre ~ 19.8 et 16.4 ka probablement liée à la déglaciation de la calotte Eurasienne. Plus récemment, les valeurs [Epsilon]Nd suggèrent une influence accrue des eaux Pacifiques sur les masses d'eaux sortantes par le détroit de Fram / Freshwater exports (sea-ice and oceanic currents) from the Arctic Ocean to the nordic seas is a critical component of the Atlantic Meridional Overturning Circulation and hence of the climatic system. Factors controling those exports are still partially unknown. An indirect way of tracing the intensity and patterns of sea-ice circulation is to trace the origin of the sediments it carries and that settle along the main drift routes towards the North Atlantic. We hence document a direct sedimentary flux that is linked to the detrital particle matrices. Another flux, this one being indirect, comes from the dissolved elements that adsorb onto particles along continental margins where sedimentary fluxes are the highest. We have extracted the authigenic (dissolved) phase from the sediment in order document the evolution of water-masses in Fram Strait since the last glacial maximum. Pb, Nd and Sr isotopic data allowed us to identify two sedimentary sources from the late glacial to the onset of the younger Dryas : canadian and western russian margins, then covered by large ice sheets. After the Younger Dryas however, sedimentary supplies originate from several sources including Greeland, Chukchi Sea and East Siberian Sea margins. The authigenic phase displays a change from 19.8 to 16.4 ka likely linked to the early deglaciation of the Eurasian ice sheet. More recently, [Epsilon]Nd values reflect a more important contribution from the Pacific on water masses exiting through Fram Strait

Integrated sequence stratigraphy and geochemistry has significantly improved our knowledge of the formation and distribution of early and late diagenetic products in North American Mississippian carbonates. Deposition of the Madison Limestone occurred in concert with a major perturbation to the global C-pool, the timing of which was constrained by comparing secular variations in the delta13C values from the Madison Limestone with limited biostratigraphy. These early constraints were then improved by peak matching of 87Sr/86Sr values from this study with European brachiopod 87Sr/86Sr. The secular variations in the delta13C values were then applied as a chronostratigraphic tool to outcrops and subsurface core. As a result, our sequence stratigraphic interpretations and knowledge regarding lateral facies variability in carbonate rocks is significantly improved. Geographic variability in the magnitude of the delta13C values is also documented along the dip-transects which suggests that marine waters experienced increasing restriction in a landward direction. These results show how local changes to the C-pool are controlled by the morphology of the depositional system which can significantly affect the original signal of the global carbon pool. The geographic variability in the delta13C and delta18O values from reservoir quality dolomites along the mid-to-upper Madison ramp suggest they also precipitated from a restricted water mass with increased salinity, temperature and alkalinity which in turn, were responsible for the distribution of massive quantities of strataform dolomite deposited during the continental transgression at the beginning of the Mississippian. Trace element and 87Sr/86Sr values from strataform dolomite suggest initial formation from Mississippian seawater and slight resetting during shallow burial diagenesis. Petrography indicates that the formation of this dolomite ceased in the shallow burial environment, between the Mississippian and Permian. These dolomites are cross-cut by comparatively small volumes of geothermal-hydrothermal dolomite associated with Laramide-age breccias and fractures. Tectonic-hydrothermal activity associated with the Laramide Orogeny was responsible for late stage calcite cemented fractures and breccias which cross-cut all carbonate rocks discussed in this thesis. Radiogenic 87Sr/86Sr, depleted delta18O and enriched delta13C values and the hottest fluid inclusions measured in this study suggest the late stage calcite formed in the hydrothermal environment and under the most open-system and water-dominated conditions. Tectonic-diagenesis is ultimately responsible for establishing vertical barriers in the otherwise porous and permeable strataform dolomites.

Following the 2010 Deepwater Horizon (DWH) spill, sediment cores were analyzed from marshes at various levels of oiling to determine how deeply oil penetrated sediment in these marsh environments, and if at these sites it had quantifiably affected benthic ecosystems. Minimum mixing depths were determined from penetration of the lithogenic radionuclide 234Th, which ranged from 0.25 to 4.5 cm. Sediment accumulation rates were determined using 210Pb, with verification from 137Cs in selected cores. Lead-210 profiles revealed long-term (decadal) mixing. Bay Jimmy, Louisiana was significantly affected by the DWH oil spill, as indicated by total polycyclic aromatic hydrocarbon concentrations of up to 21,913 ppb. This is far above the level at which adverse biological effects occur (4,022 ppb). Benthic foraminifera responded to the heavy oiling by decreases to standing stock and depth of habitation relative to unoiled sites, as well as exhibiting deformities. These data clearly show that oil can be quickly mixed into salt marsh sediments, with demonstrable impacts on indigenous benthos. Further, radioisotope inventories indicated that most of the sampled sites are in a net erosional state. Should marshes containing trapped DWH oil be submerged by rising sea level, there is a great potential for the remobilization of oil.

Made available in DSpace on 2014-06-11T19:32:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-04-04Bitstream added on 2014-06-13T19:42:59Z : No. of bitstreams: 1 trindade_ir_dr_rcla.pdf: 3348728 bytes, checksum: e5ef235a8ad9a2230bec13d0bfbd1659 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Foram usados estudos de mobilidade de elementos geoquímicos, isotópicos e petrológicos para investigar o comportamento dos isótopos radiogênicos Rb/Sr, Sm/Nd e U/Pb na formação de, migmatitos estromáticos e diatexiticos em três ambientes geotectônicos distintos. Os estudos foram realizados em migmatitos derivados de rochas metassedimentares do Grupo Seridó que teve deposição e metamorfismo no Neopreterozóico, em ortognaisses migmatíticos de composição granítica e tonalítica do Complexo Caicó de idade Paleoproterozóica e em ortognaisses migmatíticos de composição tonalítica do Complexo Presidente Juscelino no Maciço São José de Campestre de idade Arqueana. Os resultados nos micaxistos do Grupo Seridó mostraram que os leucossomas foram gerados por exsudações de quartzo e feldspatos formados a partir dos elementos Na, Ca e Si liberados do paleossoma pela fusão parcial que se individualizaram como veios. O Rb permaneceu imóvel no sistema e Sr perdeu massa, enquanto Sm e Nd permaneceram imóveis. As sistemáticas isotópicas Rb/Sr e Sm/Nd foram fortemente afetadas durante o processo de migmatização, fornecendo idades sem significado geológico. / Studies of chemical elements mobility, isotopics and petrologic were used to investigate the behavior of the radiogenic isotope Rb/Sr, Sm/Nd and U/Pb in the formation of, estromatics migmatites and diatexites in three different tectonic setting. The studies were accomplished in derived migmatites of metasedimentary rocks of the Seridó Grup Seridó that had deposition and metamorphism in Neopreterozóico, in migmatitics orthogneisses of granitic and tonalitic composition of the Caicó Complex of Paleoproterozoic age and in migmatitics orthogneisses of tonalitic composition of the President Juscelino Complex in São José de Campestre Massif of Archaean age. The results in mica-schist`s Seridó Grup showed that the leucosome was generated by exsudation of quartz and feldspars formed starting from the elements In the Ca and Si liberated of the paleosome for the melting partial that were individualized as veins. The Rb stayed immobile in the system and Sr lost mass, while Sm and Nd stayed immobile. The isotopics systematics Rb/Sr and Sm/Nd were strongly affected during the process migmatization, supplying ages without geological meaning.

abstract: Mobility is an important aspect of the lives of religious individuals described by medieval texts in early and late medieval Ireland, and biogeochemical methods can be used to detect mobility in archaeological populations. Stories are recorded of monks and nuns traveling and founding monasteries across Ireland, Scotland, England, Wales, and other areas of Europe. However, these texts rarely address the quotidian lives of average monks and nuns who lived in monastic communities. This dissertation seeks to understand if travel was a typical part of the experiences of religious and lay people in early and late medieval Ireland. It also aims to increase understanding of how monastic communities related to the local lay communities, including addressing if the monastery was populated by those who grew up in the local area. Another methodological aim of this dissertation is to advance the field of archaeological biogeochemistry by (1) adding to the bioavailable strontium baseline in Ireland and (2) quantifying the contribution of ocean-derived strontium to coastal environments. These topics are explored through the biogeochemical analysis of 88 individuals buried at 5 early and late medieval monasteries in Ireland and the analysis of a total of 85 plant samples from four counties in Ireland. The three papers in this dissertation present: (1) a summary of the mobility of religious and lay people buried at the monasteries (Chapter 2), (2) a case study presenting evidence for fosterage of a local child at the early medieval monastery of Illaunloughan, Co. Kerry (Chapter 3), and (3) a study designed to quantify the impact of sea spray on bioavailable strontium in coastal environments (Chapter 4). The majority of lay and religious individuals studied were estimated to be local, indicating that medieval Irish Christianity was strongly rooted in the local community. The study of ocean-derived strontium in a coastal environment indicates that sea spray has a non-uniform impact on bioavailable strontium in coastal regions. These findings shed new light on medieval monastic and lay life in Ireland through the application of biogeochemical methods, contributing to the growth of the field of archaeological chemistry in Ireland. / Dissertation/Thesis / Doctoral Dissertation Anthropology 2018

Master of Science / Department of Geology / Matthew E. Brueseke / The Sonya Creek volcanic field (SCVF) contains the oldest in situ magmatic products in the ~29 Ma–modern Wrangell arc (WA) in south-central Alaska. The WA is located within a transition zone between Aleutian subduction to the west and dextral strike-slip tectonics along the Queen Charlotte-Fairweather and Denali-Duke River fault systems to the east. WA magmatism is due to the shallow subduction (11–16°) of the Yakutat microplate. New ⁴⁰Ar/³⁹Ar and U-Pb geochronology of bedrock and modern river sediments shows that SCVF magmatism occurred from ~29–18 Ma. Volcanic units are divided based on field mapping, physical characteristics, geochronology, and new major and trace element geochemistry. A dacite dome yields a ~29 Ma ⁴⁰Ar/³⁹Ar age and was followed by eruptions of basaltic-andesite to dacite lavas and domes (~28–23 Ma Rocker Creek lavas and domes) that record hydrous, subduction-related, calc-alkaline magmatism with an apparent adakite-like component. This was followed by a westward shift to continued subduction-related magmatism without the adakite-like component (e.g., mantle wedge melting), represented by ~23–21 Ma basaltic-andesite to dacite domes and associated diorites (“intermediate domes”). These eruptions were followed by a westward shift in volcanism to anhydrous, transitional, basaltic-andesite to rhyolite lavas of the ~23–18 Ma Sonya Creek shield volcano (Cabin Creek lavas), including a rhyolite ignimbrite unit (~19 Ma Flat Top tuff), recording the influence of local intra-arc extension. The end of SCVF activity was marked by a southward shift in volcanism back to hydrous calc-alkaline lavas at ~22–19 Ma (Young Creek rocks and Border Lavas). SCVF geochemical types are very similar to those from the <5 WA, and no alkaline lavas that characterize the ~18–10 Ma Yukon WA are present. Sr-Nd-Pb-Hf radiogenic isotope data suggest the SCVF data were generated by contamination of a depleted mantle wedge by ~0.2–4% subducted terrigenous sediment, agreeing with geologic evidence from many places along the southern Alaskan margin. Our combined dataset reveals geochemical and spatial transitions through the lifetime of the SCVF, which record changing tectonic processes during the early evolution of the WA. The earliest SCVF phases suggest the initiation of Yakutat microplate subduction. Early SCVF igneous rocks are also chemically similar to hypabyssal intrusive rocks of similar ages that crop out to the west; together these ~29–20 Ma rocks imply that WA initiation occurred over a <100 km belt, ~50–60 km inboard from the modern WA and current loci of arc magmatism that extends from Mt. Drum to Mt. Churchill.

Understanding U-series isotopic disequilibria of partially melted crust is integral for determining the effect that crustal assimilation has on the U-series signature of magmas. In this work, U, Th and Ba (as a proxy for Ra) elemental abundances were gathered on the quenched glass in partially melted crustal xenoliths of granitic composition using microbeam techniques. The crustal xenoliths, which are found in basaltic lava, from Mirador Volcano in Chile, are old, and can be assumed to be at secular equilibrium, whereas melting occurred during eruption of Mirador in 1979. A comparison of the ratios Ba/Th and U/Th in the partial melts with those of the whole rock reveal how much fractionation has occurred during partial melting. Different ratios of U, Th and Ba compared to the whole rock substantiate fractionation via partial melting. Thus, assimilation of partial melts of crust can play a role in U-series isotopic disequilibria.

No description available.