Bibliographies thématiques / Arch. evolution

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Littérature scientifique sur le sujet « Arch. evolution »

Auteur : Grafiati
Publié le 9 mars 2023
Mis à jour le 10 mars 2023

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Articles de revues sur le sujet "Arch. evolution"

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Du, Xiao Li, Hong Wei Song et Jie Chen. « Laws of Formation and Evolution of Pressure Arch in Coal Mining Adjoining Rock ». Advanced Materials Research 243-249 (mai 2011) : 2596–600. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.2596.

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Based on numerical simulation of computing Software ANSYS, the curve of arching coefficient variation of pressure arch due to actual mining was analyzed aiming to a special mining face, the law of stress transfer and change in surrounding rock was discussed, and the evolving features and characteristics of pressure arch was obtained. The analysis and discussion show the following facts: Arch body will become thicker and stress in the arch body increases with working face’s driving distance increasing; the morphology of pressure arch transits from ellipsoid with long axis in the vertical direction to ellipsoid with long axis in the horizontal direction along the trend of working face; along the tendency of working face, the morphology of pressure arch is a ellipsoid with long axis in the vertical direction.
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Wang, S. R., X. G. Wu, Y. H. Zhao, P. Hagan et C. Cao. « Evolution Characteristics of Composite Pressure-Arch in Thin Bedrock of Overlying Strata During Shallow Coal Mining ». International Journal of Applied Mechanics 11, no 03 (avril 2019) : 1950030. http://dx.doi.org/10.1142/s1758825119500303.

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Under the shallow coal mining condition and based on the cracking and movement rules of the roof in different mining stages, the mechanical models of symmetrical pressure-arch, stepped pressure-arch, rotating-squeezed pressure-arch in the mining field were established. Then, the instability criterion of each pressure-arch structure was derived. Through the similarity material experiment and numerical simulation, the evolution characteristics of the composite pressure-arches in the near- and far-field were revealed. Results show that the stepped pressure-arch in broken blocks of the basic roof was formed when the horizontal principal stress was greater than the in-situ stress. The broken blocks’ sliding could induce roof cutting off and strong weighting load. The structural characteristics of the overlying strata were determined by the thickness of the bedrock. The upper broken rocks formed a symmetrical pressure-arch in the near- and a far-field pressure-arch formed in the mining field. The median periodic broken rocks formed the rotating-squeezed pressure-arch, bearing the load of the loose layers and protecting the mining panel. After all bedrocks breaking, the latter arch foot of the far-field pressure-arch was transferred to the compacted caving zone. This study can provide a theoretical reference for the similar mining engineering.
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Barske, Lindsey, Peter Fabian, Christine Hirschberger, David Jandzik, Tyler Square, Pengfei Xu, Nellie Nelson et al. « Evolution of vertebrate gill covers via shifts in an ancient Pou3f3 enhancer ». Proceedings of the National Academy of Sciences 117, no 40 (21 septembre 2020) : 24876–84. http://dx.doi.org/10.1073/pnas.2011531117.

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Whereas the gill chambers of jawless vertebrates open directly into the environment, jawed vertebrates evolved skeletal appendages that drive oxygenated water unidirectionally over the gills. A major anatomical difference between the two jawed vertebrate lineages is the presence of a single large gill cover in bony fishes versus separate covers for each gill chamber in cartilaginous fishes. Here, we find that these divergent patterns correlate with the pharyngeal arch expression of Pou3f3 orthologs. We identify a deeply conserved Pou3f3 arch enhancer present in humans through sharks but undetectable in jawless fish. Minor differences between the bony and cartilaginous fish enhancers account for their restricted versus pan-arch expression patterns. In zebrafish, mutation of Pou3f3 or the conserved enhancer disrupts gill cover formation, whereas ectopic pan-arch Pou3f3b expression generates ectopic skeletal elements resembling the multimeric covers of cartilaginous fishes. Emergence of this Pou3f3 arch enhancer >430 Mya and subsequent modifications may thus have contributed to the acquisition and diversification of gill covers and respiratory strategies during gnathostome evolution.
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Rusu, Ligia, Mihnea Ion Marin, Michi Mihail Geambesa et Mihai Robert Rusu. « Monitoring the Role of Physical Activity in Children with Flat Feet by Assessing Subtalar Flexibility and Plantar Arch Index ». Children 9, no 3 (18 mars 2022) : 427. http://dx.doi.org/10.3390/children9030427.

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Flat foot is a common pediatric foot deformity which involves subtalar flexibility; it can affect the plantar arch. This study analyzes the evolution of two parameters, i.e., plantar index arch and subtalar flexibility, before and after physiotherapy and orthoses interventions, and examines the correlation between these two parameters. Methods: The study included 30 participants (17 boys, 12 girls, average age 9.37 ± 1.42 years) with bilateral flat foot. We made two groups, each with 15 subjects. Assessments of the subtalar flexibility and plantar arch index used RSScan the platform, and were undertaken at two time points. Therapeutic interventions: Group 1—short foot exercises (SFE); Group 2—SFE and insoles. Statistical analyses included Student’s t-test, Cohen’s D coefficient, Pearson and Sperman correlation. Results: Group 1—subtalar flexibility decreased for the left and right feet by 28.6% and 15.9% respectively, indicating good evolution for the left foot. For both feet, a decrease of the plantar index arch was observed. Group 2—subtalar flexibility decreased for the right and left feet by 43.4% and 37.7% respectively, indicating a good evolution for the right foot. For both feet, a decrease of plantar index arch was observed. Between groups, subtalar flexibility evolved well for Group 2; this was attributed to mixt intervention, physical therapy and orthosis. For plantar arch index, differences were not significant between the two groups. We observed an inverse correlation between subtalar flexibility and plantar arch index. Conclusions: Improvement of plantar index arch in static and dynamic situations creates the premise of a good therapeutic intervention and increases foot balance and postural control. The parameter which showed the most beneficial influence was the evolution is subtalar flexibility.
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González Manrique, S. J., C. Kuckein, M. Collados, C. Denker, S. K. Solanki, P. Gömöry, M. Verma, H. Balthasar, A. Lagg et A. Diercke. « Temporal evolution of arch filaments as seen in He I 10 830 Å ». Astronomy & ; Astrophysics 617 (septembre 2018) : A55. http://dx.doi.org/10.1051/0004-6361/201832684.

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Aims. We study the evolution of an arch filament system (AFS) and of its individual arch filaments to learn about the processes occurring in them. Methods. We observed the AFS at the GREGOR solar telescope on Tenerife at high cadence with the very fast spectroscopic mode of the GREGOR Infrared Spectrograph (GRIS) in the He I 10 830 Å spectral range. The He I triplet profiles were fitted with analytic functions to infer line-of-sight (LOS) velocities to follow plasma motions within the AFS. Results. We tracked the temporal evolution of an individual arch filament over its entire lifetime, as seen in the He I 10 830 Å triplet. The arch filament expanded in height and extended in length from 13″ to 21″. The lifetime of this arch filament is about 30 min. About 11 min after the arch filament is seen in He I, the loop top starts to rise with an average Doppler velocity of 6 km s−1. Only two minutes later, plasma drains down with supersonic velocities towards the footpoints reaching a peak velocity of up to 40 km s−1 in the chromosphere. The temporal evolution of He I 10 830 Å profiles near the leading pore showed almost ubiquitous dual red components of the He I triplet, indicating strong downflows, along with material nearly at rest within the same resolution element during the whole observing time. Conclusions. We followed the arch filament as it carried plasma during its rise from the photosphere to the corona. The material then drained toward the photosphere, reaching supersonic velocities, along the legs of the arch filament. Our observational results support theoretical AFS models and aids in improving future models.
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Wang, Shuren, Xiaogang Wu, Yanhai Zhao et Paul Hagan. « Mechanical Performances of Pressure Arch in Thick Bedrock during Shallow Coal Mining ». Geofluids 2018 (1 octobre 2018) : 1–13. http://dx.doi.org/10.1155/2018/2419659.

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Due to the periodicity of mine pressure, it can easily lead to a wide-range damage of the overburden rock under shallow coal mining conditions, and the falling of the overburden rock is usually a serious threat to the mining safety. Based on the monitoring data of mine pressure in a typical shallow coal mine in northern China, the mechanical model of the surrounding rock in the mining field was built and the identification indicators of the pressure arch after coal mining was defined. Then, the arching mechanism, the stress distribution characteristics in different positions, and the bearing capacity of the pressure arch were analysed, and the evolution characteristics of the pressure arch under shallow horizontal coal mining were verified by numerical simulation and physical experiment. Results show that there is a core-bearing zone in the pressure arch, and the width of the core zone determines the bearing capacity of the pressure arch. The evolution of the pressure arch affects the formation and development of the caving arch of the loose zone in the mining field. The conclusions obtained in the study are of important theoretical value to direct the similar engineering practice.
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Raz, Sagi, Marcel Goodman, Daniel Silverberg et David Planer. « TCT-440 Further Evolution In Aortic Arch Endografting ». Journal of the American College of Cardiology 64, no 11 (septembre 2014) : B129. http://dx.doi.org/10.1016/j.jacc.2014.07.491.

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Ding, Yanchao, Zhongfu Xiang, Yayong Li, Xuesong Zhang et Yin Zhou. « Mechanical System Evolution and Reasonable Structural Design Parameters of Long-Span Deck-Type Beam-Arch Composite Rigid Frame Bridge ». International Journal of Design & ; Nature and Ecodynamics 15, no 6 (26 décembre 2020) : 885–93. http://dx.doi.org/10.18280/ijdne.150614.

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Long-span deck-type beam-arch composite rigid frame (BACRF) bridge fully integrates the merits of arch bridges and beam bridges, and overcomes the cracking and deflection problems of continuous rigid frame bridges. As a perfect combination of beam bridges and arch bridges, the long-span deck-type BACRF bridge boasts a light structure, a strong bearing capacity, and a powerful spanning capability. From the perspective of mechanical system evolution, this paper theoretically analyzes the structural mechanics of the beam-arch composite system, establishes a half-bridge model for BACRF bridge, and derives the expressions of the internal force and displacement of the beam-arch composite system. Next, finite-element analysis was conducted to analyze how the variation of a single parameter, e.g., rise-span ratio, open web ratio, and side-to-middle span ratio, affects midspan displacement, arch-beam junction displacement, main beam bending moment, and main arch axial force. Finally, the calculation formula for deflection-span ratio of BACRF bridge was proposed based on the maximum hyperplane method. The research results provide a reference for the structural design of similar bridges.
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Wang, Feng, Tong Chen, Bo Ma et Denghong Chen. « Formation mechanism of stress arch during longwall mining based on key strata theory ». Energy Exploration & ; Exploitation 40, no 2 (6 octobre 2021) : 816–33. http://dx.doi.org/10.1177/01445987211042701.

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The traditional stress arch hypothesis during longwall mining fails to elucidate the formation mechanism of stress arch, and the morphological characteristics and evolution of stress arch are indefinite. To solve these problems, a mechanical model was established for elucidating the formation mechanism of stress arch in overlaying strata. The influencing of key strata on the morphological characteristics of the stress arch was studied. Finally, the evolution of the stress arch during longwall mining was studied through numerical simulation. The results show that the bearing structure of the overlying strata served as the key strata, and the stress arch was formed when the key strata were subjected to deflection after playing a bearing structure role. This was the result of coordination and redistribution of major principal stress in the key strata. The morphological characteristics of the stress arch changed accordingly with the change in key strata. When the thickness of key strata and the distance between key strata and coal seam were gradually increased, the height and width of the stress arch increased accordingly; however, its height was always terminated at the top interface of key strata. At this time, the peak value of the abutment pressure of the working face gradually decreased while the influencing range gradually increased. During longwall mining, the stress arch developed upward by leaps and bounds with the bearing and fracture of key strata. When the overlying key strata were completely fractured, the stress arch disappeared. The results were verified using the field measurement data on the abutment pressure of the Y485 longwall face in Tangshan Mine.
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Braginsky, V. I. « Evolution of the Verse Structure of the Malay Syair ». Archipel 42, no 1 (1991) : 133–54. http://dx.doi.org/10.3406/arch.1991.2754.

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Thèses sur le sujet "Arch. evolution"

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Al-Kindi, Mohammed. « Structural evolution and fracture pattern of Salakh Arch ». Thesis, University of Leeds, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434242.

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Williams, Devin N. « The Association of Size Variation in the Dental Arch to Third Molar Agenesis for a Modern Population ». Scholar Commons, 2018. http://scholarcommons.usf.edu/etd/7247.

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The frequency with which individuals do not develop their third molars, or wisdom teeth, is increasing worldwide. This current topic of human evolution is relevant to the research of anthropologists, geneticists, dentists, and other researchers involved in the study of human dentition. Many explanations have been offered to account for the prevalence of molar agenesis including, evolutionary, environmental, and genetic theories. The purpose of this research project is to determine the frequency of third molar agenesis and investigate the relationship between third molar agenesis and maxillomandibular jaw dimensions in a sample of orthodontic patients. This research tests the hypotheses that: H1: Individuals with agenesis of third molars will be significantly different in maxillomandibular dimensions than individuals without agenesis, H2: The agenesis of maxillary third molars is associated with the anteroposterior dimensions of the maxilla, and H3: The agenesis of mandibular third molars is not associated with the anteroposterior dimensions of the mandible. Therefore, the null hypothesis for this research is H0: An individual’s sex and the presence/absence of the third molar are independent. The sample for this research project includes 543 individuals from the University of New Mexico’s Maxwell Museum of Anthropology Orthodontics Case File System. This study examines panoramic radiographs of the dentition for each individual to ascertain whether any of the third molars was congenitally absent, and records the cephalometric measurements for each case for statistical analysis. This study uses descriptive statistics, crosstabulation analysis, chi-square tests, non-parametric Kruskal-Wallis tests, and logistic regression analysis to investigate any associations between third molar agenesis and maxillomandibular jaw dimensions. The results show that Native Americans (9.2%), Hispanics (8.46%), and European Americans (8.37%) have a higher frequency of third molar agenesis than African Americans (0.17%) and Asians (0.17%). This finding is consistent with the published body of work on third molar agenesis, in spite of the small sample sizes for diverse populations. There is a significant difference in the number of molars missing among groups. For the present study, based on crosstabulation analysis, most individuals are missing two molars (34.9%), followed by one absent (31.7%), a lack of four molars (25.3%), and finally a lack of 3 molars (7.9%). Individuals with third molar agenesis are nearly twice as likely to be missing a molar from the mandible (62.8%) than the maxilla (36.9%). This study uses crosstabulation analysis, chi-square analysis, non-parametric Kruskal-Wallis tests, and logistic regression analysis to assess the association between third molar agenesis and measurements of the dental arcade. This study did not find an association between an individual’s maxillomandibular dimensions and third molar agenesis. Therefore, this study did not find support for the hypothesis that individuals with third molar agenesis would have smaller maxillomandibular dimensions than individuals without agenesis. Based on the findings of this study, an association between the size of an individual’s mouth and third molar agenesis does not exist in the sample analyzed. Third molar agenesis is not occurring due to a lack of room in the mouth, but possibly results from heredity. Therefore, it may be more likely that genetic variation influences third molar agenesis, rather than an evolutionary change in diet.
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PIGAZZINI, ILARIA. « Evaluating and Detecting Architecture Erosion ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2022. http://hdl.handle.net/10281/365009.

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Un'architettura software è erosa (o degradata) se mostra una progressiva perdita di integrità strutturale a causa di violazioni dei principi di progettazione. I sistemi erosi soffrono di Architectural Technical Debt (ATD), lo sforzo aggiuntivo richiesto agli sviluppatori per gestire i difetti causati dall'erosione. Un sintomo dell'accumulo di ATD è la presenza di Architectural Smells (AS), decisioni di software design che hanno un impatto negativo sulla qualità interna del sistema software. I sistemi affetti da AS soffrono di maggiori costi di manutenzione e sono più difficili da evolvere. Questa tesi indaga sei diversi tipi di AS che violano diversi principi di design in progetti Java monolitici Open-Source e industriali. Identifichiamo gli AS con il nostro strumento, Arcan, e introduciamo la sua nuova estensione per la rappresentazione dei software concerns. Discutiamo poi gli AS dal punto di vista dei professionisti, cercando di riassumere come gli AS sono percepiti e validando i risultati di Arcan. Riportiamo anche i risultati dei nostri studi empirici riguardanti l'evoluzione e la correlazione di AS e ATD. Infine, presentiamo i nostri primi risultati riguardanti la migrazione e la manutenzione di architetture a microservizi, con particolare attenzione al rilevamento degli odori dei microservizi.
A software architecture is eroded (or degraded) if it shows a progressive loss of structural integrity due to design principle violations which leads to the deviation of the implemented architecture from the intended architecture. Eroded systems suffer from Architectural Technical Debt (ATD), the additional effort required by developers to manage the shortcomings caused by the erosion. A symptom of the accumulation of ATD is the presence of Architectural Smells (AS), design decisions that impact negatively on the internal system quality. Systems affected by AS suffer from higher maintenance costs and are harder to evolve. This thesis investigates six different types of AS violating different design principles in Open-Source and industrial monolithic Java projects. We identify AS with our tool, Arcan, and introduce its new extension for the representation of software concerns. We then discuss AS from the point of view of practitioners, trying to summarise how AS are perceived and validating Arcan results. We also report the results of our empirical studies concerning AS and ATD evolution and correlation. Finally, we present our first results concerning the migration and maintenance of microservices architectures, with a focus on the detection of microservices smells.
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Talbot, Jared Coffin 1982. « Patterning and Stabilizing the Zebrafish Pharyngeal Arch Intermediate Domain ». Thesis, University of Oregon, 2011. http://hdl.handle.net/1794/11982.

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xv, 76 p. : ill. (some col.) Includes 4 video files.
Improved understanding of pharyngeal arch (PA) patterning and morphogenesis can reveal critical insights into the origins of craniofacial diseases, such as Fraser syndrome. PAs contain mesenchymal condensations, which give rise to most of the facial skeleton in vertebrates. Studies of Endothelin1 signaling reveal that the skeleton derived from the first two PAs are patterned into dorsal, intermediate, and ventral domains. Previous work has indicated that endothelin targets, including the Dlx genes, homeotically pattern dorsal versus ventral PA identity. I show that the Dlx gene family plays a vital role in PA intermediate-domain identity establishment. In WT fish, the PA intermediate domain is delineated by combined expression of all Dlx genes. Reduction of Dlx gene function results in loss of intermediate-domain identity. Conversely, ventral expansion of Dlx expression, seen in hand2 mutants, results in ventral expansion of intermediate-domain identity. Hence, PA intermediate-domain identity is defined by co-expression of Dlx genes. Epithelial-mesenchymal interactions play an important part in PA intermediate-domain morphogenesis. Zebrafish fras1 (epithelially expressed) and itga8 (mesenchymally expressed) mutants also show specific defects within intermediate-domain skeleton and epithelia. Facial phenotypes in fras1;itga8 double mutants look extremely similar to either single mutant, suggesting that fras1 and itga8 might participate in the same epithelial-mesenchymal interaction during PA intermediate-domain formation. Our developmental studies reveal that fras1 - and itga8 -dependent epithelial segmentation of the PA intermediate domain stabilizes developing skeletal elements. Lesions in human FRAS1 underlie many cases of Fraser syndrome, and this work provides an excellent developmental model for the craniofacial defects found in Fraser syndrome. Loss of either Dlx or fras1 function produces defects in the PA intermediate domain, yet seemingly during different developmental periods. Nonetheless, combined reduction of both Dlx and fras1 function synergistically increases skeletal defects, implying a molecular connection between early (Dlx -mediated) pattern formation and later (fras1 -mediated) pattern stabilization. Elucidation of the Dlx-fras1 interaction is an interesting topic which may unveil new molecules pertinent to Fraser syndrome. Supplemental movies highlighting skeletal and epithelial morphogenesis accompany this dissertation.
Committee in charge: Judith S. Eisen, Chairperson; Charles B. Kimmel, Advisor; John H. Postlethwait, Member; Chris Q. Doe, Member; Kennith E. Prehoda, Outside Member
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Morris, Aisha R. « Emplacement of deep submarine lava flows on the North Hawaiian Arch : a study of thermal and rheological evolution using a numerical model ». Thesis, University of Hawaii at Manoa, 2003. http://hdl.handle.net/10125/6982.

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Edwards, Caroline Marion Hawkey. « A comparison of arc evolution on continental and oceanic crust, Sunda Arc, Indonesia ». Thesis, Royal Holloway, University of London, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361452.

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Kadarusman. « Rainbowfishes from west Papua (Melanotaeniidae) : evolution and systematics ». Toulouse 3, 2012. http://www.theses.fr/2012TOU30079.

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Située au Nord de l'Australie, la Nouvelle Guinée se caractérise par des reliefs montagneux très développés et demeure l'une des dernières régions inexplorées de la planète. Des processus complexes de géodynamique couplés a son isolement géographique ont contribué à la mise en place d'un panel complexe d'écosystèmes et à l'évolution d'une biodiversité exceptionnelle. Cette particularité vaut également pour la diversité de sa faune ichtyologique. Les poissons arc-en-ciel (Melanotaeniidae) constituent avec les Eleotridae et les Gobiidae, les 3 familles de poissons les plus diversifiées des eaux douces de Nouvelle Guinée et même d'Australie. La taxonomie des poissons arc-en-ciel est ancienne et a connu un regain d'intérêt durant ces dernières décennies avec la description d'une cinquantaine d'espèces nouvelles. Malgré un nombre important d'espèces décrites, la taxonomie des Melanotaeniidae demeure encore confuse avec des diagnoses incomplètes basées sur des comptages ou des caractères morphologiques. Les rares données moléculaires et phylogénétiques disponibles pour quelques espèces de Melanotaeniidae sont également incomplètes et ne permettent pas de valider les hypothèses taxonomique ou évolutive proposées par plusieurs auteurs. Les résultats présentés dans cette thèse apportent une contribution significative dans la compréhension des processus de diversification des poissons arc-en-ciel de Papouasie Occidentale et plus largement des régions adjacentes comprenant le reste de la Nouvelle Guinée et le nord de l'Australie. Ils proposent également une révision taxonomique complète des espèces peuplant la Papouasie Occidentale avec 28 espèces valides et incluant 15 espèces nouvelles
New Guinea Island is an immense, rugged landscape and remains one of the last unexplored places. This is particularly true for its ichthyological fauna. With freshwater Gudgeon and Gobiids, the Austro-New Guinean rainbowfishes are the most diverse groups with important endemism. Rainbowfish taxonomy is ancient and recently attracted much attention for various domains interest. Despite a large number of species already described, their taxonomy remains incomplete and somewhat confused. Data on their phylogenetic relatedness or biogeographical history are scarce. The results presented here give a contribution to diversification processes of Rainbowfishes from West Papua and adjacent biogeographic region and provide a complete taxonomic revision of the Western New Guinean species. A total of 716 specimens belonging to 3 genera have been studied in morphology and molecular relatedness. Molecular phylogenies were inferred from 3 mitochondrial regions (Cox-1, Cyt-b, D-loop) and 1 nuclear intron (S7). The dataset includes more than 5,000 base pairs with a portion of DNA Barcodes. The choice of both mitochondrial and nuclear molecular markers was driven by the multiple objectives to resolve deeper and shallow radiations and to evidence possible hybridization events. The phylogenies revealed an unexpected cryptic diversity within the genus Melanotaenia and strongly supported the polyphyly of the genera Glossolepis and Chilatherina. The results also revealed a strong congruence between phylogenetic relatedness, clade composition and geography and confirmed that the center of origin of Melanotaenia sensu lato was dated to the Mid-Miocene in the Bird's Head Peninsula. The eological context of the area revealed that the formation of the Lengguru fold-and-thrust Belt together with the ridge of the Central Dividing Range were the main events responsible of the basal diversification processes within this group of obligate freshwater fishes
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Bignold, Stella Mary. « The initiation and magmatic evolution of a juvenile island arc : the Kohistan arc, Pakistan Himalaya ». Thesis, Kingston University, 2001. http://eprints.kingston.ac.uk/20671/.

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The Kohistan arc, situated in the northwestern Himalaya of North Pakistan, is a Cretaceous intra-oceanic island arc which was erected during subduction of the Tethys Ocean consequent on the northward flight of India. Following accretion to the Asian margin, the arc behaved as an Andean-type continental arc prior to the collision of India with the Asian continent, which uplifted the arc and tilted it, thus providing a unique opportunity to study a complete succession of rocks from the very earliest stages of arc evolution. A combination of fieldwork, geochemical and radiogenic isotope analysis, and rare earth element modelling are used to determine the main magma sources in the mantle beneath the arc. The Kamila Amphibolites fall into two successions. The 'E-type' rocks have a MORB-type signature and were formed from 6% partial melting of a primitive, garnet¬bearing, mantle source. The 'D-type' Kamila Amphibolites have an arc signature and represent the earliest arc volcanic rocks. They originated from 15.5% partial melting of a primitive spinel-bearing, mantle source. The Jaglot Group (Gashu Confluence Volcanics and Peshmal Volcanics) and Western Volcanics of the Chalt Volcanic Group were generated by 7.5%, 13% and 2.5% partial melting, respectively, of a primitive, garnet¬bearing, mantle source. The Hunza Valley Volcanics of the ChaIt Volcanic Group, which contain boninites, have MORB-type chemistries and an arc signature. These rocks were generated from 15% melting of a depleted, spinel-bearing mantle source which may be the residuum from partial melting which produced the 'E-type' Kamila Amphibolites. That the Hunza Valley Volcanics were generated from this source is consistent with the 'E-type' Kamila Amphibolites fonning the basement and the Hunza Valley Volcanics occurring in the back-arc. Radiogenic Nd, Sr and Pb isotope analyses address an hypothesis that the magmas were generated from 'Dupal' -type mantle. The results indicate that this is not the case, but show that the isotopic chemistry of the rocks is the result of fluids from dehydration and melting of sediments carried on the downgoing ocean crust into the subduction zone affecting magma chemistry. A recent controversy concerns the polarity of subduction beneath the arc. This is partly' based on the presence of boninites, and the prevalent understanding that this rock-type occurs solely in the fore-arc. Evidence from this thesis suggests that the boninites of the Hunza Valley Volcanics were erupted into a back-arc setting, and arguments are made that boninites may also be erupted into the back-arc, and that the polarity of subduction was to the north. A model is presented for the erection of the Kohistan arc in which subduction was initiated by gravitational instability at an oceanic transform fault which connected two mid-ocean spreading ridge segments. The first arc magmas were generated by decompression melting beneath extending lithosphere during initial subsidence, and as this turned into subduction, magmas were generated at progressively greater depths in the spinel and garnet lherzolite facies, respectively. Lithospheric extension and rifting behind the volcanic front provided the setting for deompression melting to produce the back-arc Hunza Valley Volcanics, including high-Mg basalts and andesites. The arc signature in these rocks became reduced as the spreading centre developed and became progressively removed from the vicinity of the subduction zone.
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Noury, Mélanie. « Evolution géologique de l'avant-arc sud péruvien : apports des données géo-thermochronologiques ». Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENU058/document.

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La marge sud péruvienne est située au niveau d’une zone majeure de subduction océan continent depuis au moins le Paleozoique inférieur. C’est dans ce cadre que s’est formé l’un des plus importants orogènes du monde : les Andes Centrales. En effet, l’épaisseur crustale y est >60 km et ce sur une importante surface. Cependant, on considère actuellement que ce surrépaississement a été acquis incrémentalement seulement depuis ~30 Ma. Dans le but de comprendre comment et quand ce surrépaississement est apparu, la majeure partie des études précédentes s’est focalisée sur l’évolution de l’arc magmatique et sur l’histoire de la déformation, du soulèvement et de l’érosion de la zone d’arrière arc. Cependant, l’évolution tectonique et thermique de l’avant arc reste mal connue bien que cette zone soit susceptible de bien enregistrer les changements liés à la dynamique de subduction.Cette thèse à pour objectif de mieux contraindre l’évolution thermique et les couplages entre les processus magmatiques, tectoniques et sédimentaires depuis 200 Ma dans l’avant-arcactuel du sud du Pérou. De nouvelles données géo-thermochronologiques couplées à une nouvelle carte tecto-stratigraphique éclaircissent l’évolution de la marge péruvienne depuis le Jurassique. Trois périodes clefs sont analysées dans ce mémoire : le début de l’épaississement crustal, les déformations de l’avant-arc associées à la formation de l’Orocline bolivien et l’épaississement crustal de l’orogène des Andes Centrales pendant le Néogène.Nous montrons que l’épaississement crustal a probablement commencé entre 90 et 50Ma après plus de 200 Ma d’amincissement, et ce a la faveur d’une évolution en trois étapes :croissance initiale (90-74 Ma), « flare-up » (74-62 Ma) et effondrement extensionnel (62-50Ma). L’extension a ensuite prédominé dans l’avant-arc tout en diminuant progressivement jusqu’à ~30 Ma. Par ailleurs, nous mettons en évidence d’importantes zones de faillesnormales orientées perpendiculairement à la marge sud-péruvienne et qui délimitent de grands blocs basculés vers le nord-ouest. Ces déformations révèlent une extension parallèle à l’orogène dans l’avant arc pendant le Paléogène, probablement due à la formation de l’Orocline bolivien par rotation antihoraire de blocs rigides. Enfin, les traits géomorphiques visibles dans la zone cotiere du sud du Pérou permettent de définir deux périodes de soulèvement de la surface (entre 23 et 10 Ma et depuis ~4.5 Ma), séparées par une période de subsidence (entre ~10 et ~4.5 Ma). La même chronologie ayant été décrite sur le versant Amazonien de l’orogène, nous proposons que cette évolution soit due à des variations à grande échelle de l’épaisseur crustale ; le soulèvement de la surface étant provoqué par addition à la croûte de magma d’origine mantellique et la subsidence par un flux de matériel crustal ductile depuis les zones précédemment sur-épaissies
The southern Peruvian margin has been located above a major ocean-continentsubduction zone since at least the Early Paleozoic, resulting in the formation of one of thelargest orogens in the world: the Central Andes, where crustal thickness is >60 km over a largearea. This overthickening is currently thought to have occurred incrementally only during thelast 30 Ma. To understand how and when crustal overthickening was acquired, most of theprevious studies have focused on the magmatic arc evolution and on deformation, uplift anderosion history of the backarc. The tectono-thermal Cenozoic evolution of the forearc remainspoorly known, whereas it is a zone prone to recording changes in subduction dynamics.The objective of this dissertation is to address the thermal evolution and the couplingbetween magmatic, tectonic and sedimentary processes over the past 200 Ma in the presentdayforearc of southern Peru where the crust thickens from ~30 km along the coastline tomore than 60 km under the present-day volcanic arc. New geo- and thermochronological datacoupled to a novel geological map illuminate the evolution of the south Peruvian margin sincethe Jurassic. Three key periods of the margin evolution are addressed in this dissertation: theonset of crustal thickening, the deformations associated in the forearc with the formation ofthe Bolivian Orocline and the Neogene crustal thickening of the Central Andean orogen.We show that crustal thickening likely began between 90 and ~50 Ma after more than200 My of lithospheric thinning during a three step evolution of the magmatic arc as follows:growth (90-74 Ma), flare-up (74-62 Ma), extensional collapse (62-50 Ma). Extension prevailedin the forearc since then and waned until ~30 Ma. In addition, we evidence important normalfault zones striking perpendicular to the southern Peruvian margin that delineate largenorthwestward tilted blocks. This deformation reveals orogen parallel extension in the forearcduring the Paleogene likely due to the formation of the Bolivian Orocline by counterclockwiserotation of rigid blocks. Finally, geomorphic features in the coastal area of southern Perureveal two periods of surface uplift (~23 to 10 Ma and since ~4.5 Ma), separated by a period ofsurface subsidence (from ~10 to ~4.5 Ma). The same chronology has been described on theAmazonian side of the Central Andean orogen. We thus propose that this evolution is due tolarge-scale crustal thickness variations; surface uplift being triggered by addition of mantlederivedmagmas to the crust and subsidence by ductile flow away from the previouslyoverthickened crust
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Hollis, Steven Philip. « Evolution and mineralization of volcanic arc sequences : Tyrone Igneous Complex, Northern Ireland ». Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/359062/.

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The Tyrone Igneous Complex of Northern Ireland forms an integral part of the Grampian-Taconic orogen, linking the well documented sectors of Scotland, western Ireland and Newfoundland. The orogen records the accretion of a series of peri-Laurentian affinity arcs, ophiolites and microcontinental blocks to the Laurentian margin between the Late Cambrian and Middle Ordovician. The Tyrone Igneous Complex is broadly divisible into two distinct units: the c. 484-480 Ma ophiolitic Tyrone Plutonic Group and the structurally overlying c. 475-469 Ma arc-related Tyrone Volcanic Group. Both were intruded by a synvolcanogenic and syncollisional, to postcollisional high-level ensialic intrusive suite between c. 470 and 464 Ma associated with their coeval obduction to an outboard peri-Laurentian microcontinental block, the Tyrone Central Inlier, at c. 470 Ma. The Tyrone Plutonic Group is principally composed of amphibolite-facies layered and isotropic gabbros, sheeted dolerite dykes and rare pillow lavas. Tholeiitic suprasubduction affinity geochemical characteristics, Nd- isotope constraints, zircon inheritance, and the presence of late Fe-Ti enriched post-obduction dykes suggest the Tyrone Plutonic Group formed above a N-dipping subduction zone by the propagation of a spreading centre into a microcontinental block. The Tyrone Volcanic Group is characterized by mafic to intermediate lavas, tuffs, rhyolite, banded chert, ironstone and argillaceous sedimentary rocks cut by numerous high-level synvolcanogenic intrusive rocks. Geochemical signatures are consistent with formation in an evolving peri-Laurentian island-arc which underwent several episodes of rifting. High LILE and LREE enrichment, calc- alkaline geochemical signatures and strongly negative εNd t values suggest the Tyrone arc was at least partially founded on a fragment of microcontinental crust, which may have rifted off the Tyrone Central Inlier during the formation of the Tyrone Plutonic Group. Stong temporal, stratigraphic, and geochemical correlations with elements within the Annieopsquotch Accretionary Tract of Newfoundland suggest the Tyrone Igneous Complex represents a third phase of arc-ophiolite obuction in the Irish Caledonides during the Grampian-Taconic orogeny and may potentially host significant VMS mineralization. Through a combination of field mapping and petrochemistry several stratigraphic horizons have been identified in the Tyrone Igneous Complex, favourable for the formation and preservation of VMS deposits. Each is closely associated with hydrothermal alteration, synvolcanogenic faults and high-level synvolcanogenic intrusions of dolerite, gabbro, diorite and tonalite. Episodic rifting is recorded by the eruption of: abundant non-arc type Fe-Ti enriched eMORB (‘icelandite’), island-arc tholeiite, OIB-like alkali basalt, high-temperature tholeiitic rhyolites with flat to U-shaped REE profiles, and high-Zr rhyolites, within the calc-alkaline dominated sequence. Rift related mafic lavas occur in the hangingwall to VMS-style mineralization and are closely associated with ironstones (often Au-bearing) and/or argillaceous sedimentary rocks representing volcanic quiescence. Extensive hydrothermal alteration, characterized by Na-depletion, high Ba/Sr, Bi, Sb, Ni, CCPI, AI and variable MgO and CaO, allows specific target areas to be identified. In the lower bimodal-mafic Tyrone arc and backarc, hydrothermal alteration is associated with Zn-Cu mineralized float. Pb-Zn-Cu-Au mineralization occurs in silicified auriferous rhyolite domes/flows and/or volcaniclastic rocks of the syncollisional bimodal-felsic upper Tyrone arc. Ophiolite hosted Cu mineralization is characterized by chalcopyrite stringers hosted in sheeted dyke sequences.
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Livres sur le sujet "Arch. evolution"

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Greiling, Reinhard, et Helga De Wall. Magmatic evolution of a neoproterozoic island-arc : Syn- to post-orogenic igneous activity in the Anti-Atlas (Morocco). Jülich : Forschungszentrum Jülich, Central Library, 2001.

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Edmonds, M., Georg F. Zellmer et S. M. Straub. The role of volatiles in the genesis, evolution and eruption of arc magmas. London : The Geological Society, 2015.

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United States. National Aeronautics and Space Administration., dir. A mathematical model of the structure and evolution of small scale discrete auroral arcs. Ithaca, N.Y : School of Electrical Engineering and Laboratory of Plasma Studies, Cornell University, 1990.

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François, Hammer, dir. Building galaxies : From the primordial universe to the present : proceedings of the XIXth Rencontres de Moriond, Les Arcs, France, 13-20 March, 1999. Singapore : World Scientific, 2000.

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Olivier, Buchsenschutz, dir. L' evolution du canton de Levroux d'apre s les prospections et les sondages arche ologiques. Levroux : Association pour la de fense et l'e tude du canton de Levroux, 1988.

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Dijk, Johannes Petrus van. Late Neogene fore-arc basin evolution in the Calabrian Arc (central Mediterranean) : Tectonic sequence stratigraphy and dynamic geohistory : with special reference to the geology of Central Calabria = Laat Neogene voor-boog bekken evolutie in de Calabrese Boog (Centrale Middellandse zeegebied) : tekonische sekwentie-stratigrafie en dynamische geohistory : met speciale referentie naar de geologie van centraal Calabrië. [Utrecht : Faculteit Aardwetenschappen der Rijksuniversiteit te Utrecht, 1992.

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-C, Wezel F., et International Conference on the Origin of Arcs (1986 : Urbino), dir. The origin and evolution of arcs : Selected papers from the International Conference on the Origin of Arcs, held at the University of Urbino,Central Italy, September 22-25, 1986. Amsterdom : Elsevier, 1988.

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Francheteau, J., et J. W. H. Monger. Circum-Pacific Orogenic Belts and Evolution of the Pacific Ocean Basin. Wiley & Sons, Limited, John, 2013.

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H, Monger J. W., Francheteau Jean et International Geological Congress (27th : 1984 : Moscow, Russia), dir. Circum-Pacific orogenic belts and evolution of the Pacific Ocean Basin. Washington, D.C : American Geophysical Union, 1987.

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Petrology and tectonic evolution of pre-Tertiary rocks of the Blue Mountains region. Washington : U.S. G.P.O., 1995.

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Chapitres de livres sur le sujet "Arch. evolution"

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Espurt, Nicolas, Patrice Baby, Stéphane Brusset, Martin Roddaz, Wilber Hermoza et Jocelyn Barbarand. « The Nazca Ridge and Uplift of the Fitzcarrald Arch : Implications for Regional Geology in Northern South America ». Dans Amazonia : Landscape and Species Evolution, 89–100. Oxford, UK : Wiley-Blackwell Publishing Ltd., 2011. http://dx.doi.org/10.1002/9781444306408.ch6.

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Rodríguez-Fernández, N. J., J. Martín-Pintado et P. De Vicente. « The Ionized Gas in the Galactic Center Radio Arc ». Dans The Evolution of Galaxies, 333–34. Dordrecht : Springer Netherlands, 2002. http://dx.doi.org/10.1007/978-94-017-3311-3_73.

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Lamiroy, Bart, et Yassine Guebbas. « Robust and Precise Circular Arc Detection ». Dans Graphics Recognition. Achievements, Challenges, and Evolution, 49–60. Berlin, Heidelberg : Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-13728-0_5.

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Bribiescas, Richard G., et Erin E. Burke. « Health, Evolution, and Reproductive Strategies in Men : New Hypotheses and Directions ». Dans The Arc of Life, 77–97. New York, NY : Springer New York, 2017. http://dx.doi.org/10.1007/978-1-4939-4038-7_6.

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Arculus, R. J., et L. J. Ruff. « Genesis of Continental Crust : Evidence from Island Arcs, Granulites, and Exospheric Processes ». Dans Granulites and Crustal Evolution, 7–23. Dordrecht : Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-2055-2_2.

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Beilis, Isak. « Cathode Spot Theories. History and Evolution of the Mechanisms ». Dans Plasma and Spot Phenomena in Electrical Arcs, 545–98. Cham : Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-44747-2_15.

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Arculus, Richard J. « Evolution of arc magmas and their volatiles ». Dans Geophysical Monograph Series, 95–108. Washington, D. C. : American Geophysical Union, 2004. http://dx.doi.org/10.1029/150gm09.

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Maffione, Marco. « Kinematic Evolution of the Southern Andean Orogenic Arc ». Dans Geodynamic Evolution of the Southernmost Andes, 173–200. Cham : Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-39727-6_7.

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Kwok, Sun, Kate Y. L. Su et J. A. Stoesz. « Circumstellar Arcs in AGB Post-AGB Stars ». Dans Post-AGB Objects as a Phase of Stellar Evolution, 115–20. Dordrecht : Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-015-9688-6_17.

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Beilis, Isak. « Theoretical Study of Anode Spot. Evolution of the Anode Region Theory ». Dans Plasma and Spot Phenomena in Electrical Arcs, 829–91. Cham : Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-44747-2_20.

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Actes de conférences sur le sujet "Arch. evolution"

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Harkrider, J. D., W. W. Aud, C. L. Cipolla et J. T. Hansen. « The Evolution of an Applied Hydraulic Fracture Project, Frontier Formation Moxa Arch, Wyoming ». Dans Low Permeability Reservoirs Symposium. Society of Petroleum Engineers, 1995. http://dx.doi.org/10.2118/29550-ms.

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Shea, Neil. « The evolution and performance of the Henderson Mine’s C-arch shotcrete drawpoint support ». Dans Ninth International Symposium on Ground Support in Mining and Underground Construction. Australian Centre for Geomechanics, Perth, 2019. http://dx.doi.org/10.36487/acg_rep/1925_17_henderson.

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MacNaughton, Robert B., Karen M. Fallas, Brian R. Pratt, Bernard C. MacLean et Elizabeth C. Turner. « TECTONIC EVOLUTION OF THE MACKENZIE ARCH, A MAJOR CONTROL ON CAMBRIAN DEPOSITIONAL PATTERNS IN THE WESTERNMOST NORTHWEST TERRITORIES, CANADA ». Dans GSA Annual Meeting in Denver, Colorado, USA - 2016. Geological Society of America, 2016. http://dx.doi.org/10.1130/abs/2016am-281200.

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Röth, Joschka, Yury Alexeevich Karpov, Anton Georgievich Kalmykov, Ekaterina Viktorovna Beseleva, Ralf Littke et Georgy Alexandrovich Kalmykov. « Thermo-Tectonic Evolution and Numerical Petroleum System Modeling of One of the Oil Fields on Krasnoleninsky Arch, SW West Siberian Basin ». Dans SPE Russian Petroleum Technology Conference. Society of Petroleum Engineers, 2020. http://dx.doi.org/10.2118/201959-ms.

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Röth, Joschka, Yury Alexeevich Karpov, Anton Georgievich Kalmykov, Ekaterina Viktorovna Beseleva, Ralf Littke et Georgy Alexandrovich Kalmykov. « Thermo-Tectonic Evolution and Numerical Petroleum System Modeling of One of the Oil Fields on Krasnoleninsky Arch, SW West Siberian Basin (Russian) ». Dans SPE Russian Petroleum Technology Conference. Society of Petroleum Engineers, 2020. http://dx.doi.org/10.2118/201959-ru.

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Fenu, Luigi, et Giuseppe C. Marano. « Steel Truss-Type Arches Optimization Under Multi-Load Cases ». Dans IABSE Congress, New York, New York 2019 : The Evolving Metropolis. Zurich, Switzerland : International Association for Bridge and Structural Engineering (IABSE), 2019. http://dx.doi.org/10.2749/newyork.2019.1338.

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<p>Structural optimization of arches under multi-load cases is faced. For this aim, truss-type arches are to be considered because, under different load cases, bending effects unavoidably occur in single-rib arches shaped under one load case only. An effective procedure for simultaneous topology, shape and size optimization of truss-arches under multi-load cases is proposed. For this aim, shape, size and topology variables are assembled in a unique set of variables that are simultaneously optimised by the optimization algorithm. For given Pratt-type brace pattern, different topologies have been considered by varying the node number, whereas Cubic Rational Bézier curves have been used to shape the arch chords. Optimum diameter and thickness of the circular hollow section members was also obtained. Optimization was performed in MATLAB environment, by applying a modified Differential Evolution (DE) algorithm implemented with a Constraint Domination Selection (CDS) criterion. For each design variable vector, a FEM analysis of the resulting model has been carried out by SAP2000 to evaluate the objective function value (volume) feasibility of each design variable vector in terms of structural performance. Optimal solutions have been found and compared, providing useful suggestions to consider as guidelines in truss-arche design.</p>
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Riandini, P. « Structural Evolution Using Seismic Low Frequency Magnitude Approach : A Case Study on Defining Strike-Slip Development in West Natuna Basin, Indonesia ». Dans Digital Technical Conference. Indonesian Petroleum Association, 2020. http://dx.doi.org/10.29118/ipa20-g-290.

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West Natuna Basin (WNB) is located in the centre of Sunda Shelf in South China Sea; bordered by the Sunda Shelf's basement to the south, the Natuna Arch to the east, and the Khorat Swell to the north. Tectonic evolution of the WNB has imparted a complex structural history of extension, compression and wrenching related to Cenozoic regional tectonic events, for which the structural evolution reflects a history of Late Eocene-Early Oligocene rifting and Middle-Late Miocene inversion. The regional strike-slip movement that associates to the Three Pagodas Fault System has long been recognised at WNB. However, the understanding of this strike-slip behaviour has not previously been investigated despite its important role in reservoir mapping. This study aims to demonstrate how new approaches of seismic attributes analysis combined with structural evolution through palinspastic reconstruction will define the structural geometry as a key point for fault relationship in the production field. Structure map and cross section are generated by integrating wells data and 3D seismic to identify structural trends. Seismic low frequency magnitude has been generated as an attribute to define faults through Spectral Decomposition method. As the faults feature on the seismic are more related to low or even absent of energy, these attributes provide robust attributes to identify four morphology in study area that represent different structural geometry and history. Seismic interpretation shows the structure commences in the early part of the Late Eocene that developed as NE-SW rifting. The rifting is initiated due to creation of pull-apart basins, as part of the WNW-ESE sinistral strike-slip fault development. The major sinistral strike-slip development was accommodated by collision of India that causes onset of rotation of Sundaland. In relation to the oblique NNE-SSW compression, Middle-Late Miocene inversion follows the post-rift deformation. This condition accommodates the development of NW-SE right lateral strike-slip on the marginal fault and result in N-S trending horsetail structure development that plays a role as an essential structure for reservoir trap.This research verifies that the combination between recent re-evaluations of the 3D seismic and its attributes can identify more detailed fault positions to generate better definitions of fault patterns. Therefore, palinspastic restoration becomes one of the classic approaches that brings further comprehension of the fault pattern’s structural evolutions, which leads to the site-development and production’s improvements.
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Zhu, Xun, P. C. Sui et Ned Djilali. « Effect of Channel Geometry on the Dynamics of a Water Droplet in a Microchannel ». Dans ASME 2008 First International Conference on Micro/Nanoscale Heat Transfer. ASMEDC, 2008. http://dx.doi.org/10.1115/mnht2008-52242.

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The objective of the present study is to investigate the effects of the microchannel geometry on the dynamic behaviour of liquid water emerging from a pore into a microchannel of a cross gas flow. The flow characteristics are resolved using the volume-of-fluid (VOF) method in conjunction with an interface tracking technique. A microchannel with dimensions of a typical proton exchange membrane fuel cell (PEMFC) gas channel (a square cross section of 250 μm in width) and a pore of 50 μm in diameter on the bottom wall is adopted as the baseline case. Simulations for microchannels of different cross sections, including trapezoid, upside-down trapezoid, triangle, rectangle, and rectangle with a arch bottom wall, are performed and the results are compared with the baseline case. The evolution of liquid water includes stages identified as emergence, growth, deformation, detachment, and remove. The simulations show that the cross section of the microchannel has significant impacts on the dynamics of the water droplet. The detachment time and diameter and the remove time of the water droplet are found to be in this order: triangle < trapezoid < rectangle with arch bottom wall < rectangle < upside-down trapezoid. The present study will advance our understanding in the transport of liquid water in a PEMFC where water is produced in the catalyst layer and flows through the pores of the porous electrode to the gas channel.
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Griffith, Christine, James Pospichal, Eric de Kaenel, Michael Pope et Arthur Donovan. « Regional sequence stratigraphy and biostratigraphic correlations of the Upper Cretaceous Austin Chalk in south and central Texas : Insights into the evolution of the San Marcos Arch ». Dans Second International Meeting for Applied Geoscience & Energy. Society of Exploration Geophysicists and American Association of Petroleum Geologists, 2022. http://dx.doi.org/10.1190/image2022-3749638.1.

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Algattas, Hanna, David McCarthy, David K. Hamilton, David O. Okonkwo, Eric W. Wang, Carl H. Snyderman, Paul A. Gardner et Georgios A. Zenonos. « An Institutional Evolution of Endoscopic Endonasal Odontoidectomy : From Occipito-Cervical Fusion to Atlanto-Axial Fusion to Partial Anterior Arch of C1 Resection, and Utilization of a Retropharyngeal Vascularized Flap ». Dans Special Virtual Symposium of the North American Skull Base Society. Georg Thieme Verlag KG, 2021. http://dx.doi.org/10.1055/s-0041-1725319.

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Rapports d'organisations sur le sujet "Arch. evolution"

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MacLean, B. C., K. M. Fallas et T. Hadlari. The evolution of Keele Arch, a multiphase feature of the northern mainland, Northwest Territories. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2015. http://dx.doi.org/10.4095/293877.

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Lucas, S. B., et M. R. St-Onge. Evolution of Archean and Early Proterozoic Magmatic Arcs in northeastern Ungava Peninsula, Quebec. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1991. http://dx.doi.org/10.4095/132566.

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Zagorevski, A., et C. R. van Staal. Cordilleran magmatism in Yukon and northern British Columbia : characteristics, temporal variations, and significance for the tectonic evolution of the northern Cordillera. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/326063.

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Geochemical and temporal characterization of magmatic rocks is an effective way to test terrane definitions and to evaluate tectonic models. In the northern Cordillera, magmatic episodes are mostly interpreted as products of continental arc and back-arc settings. Re-evaluation of Paleozoic and Late Mesozoic magmatic episodes presented herein highlights fundamental gaps in the understanding of the tectonic framework of the northern Cordillera. In many cases, the character of magmatism and temporal relationships between various magma types do not support existing tectonic models. The present re-evaluation indicates that some of the magmatic episodes are best explained by lithospheric extension rather than arc magmatism. In addition, comparison to modern analogues suggests that many presently defined terranes are not the fundamental tectonic building blocks, but rather combine distinctly different tectonic elements that may not be related each other. Grouping of these distinctly different tectonic elements into single terranes hinders the understanding of Cordilleran evolution and its mineral deposits.
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Kellett, D. A., et A. Zagorevski. Overlap assemblages : Laberge Group of the Whitehorse Trough, northern Canadian Cordillera. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/326064.

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The Laberge Group was deposited during the Early to Middle Jurassic in a marginal marine environment, in the northern Canadian Cordillera. It occurs as a narrow, elongated siliciclastic unit along more than 600 km of strike length, overlapping the Intermontane terranes of southern Yukon and northwestern British Columbia. The Laberge Group was deposited on the Late Triassic Stuhini and Lewes River groups, a volcano-plutonic complex of the Stikine terrane (Stikinia), and, locally, the Kutcho Arc. It is overlain by Middle Jurassic to Cretaceous clastic units. The variations in clast composition and detrital zircon populations among these units indicate major changes in depositional environment, basin extent, and sources during the latest Triassic to Middle Jurassic. Detrital zircon populations are dominated by near contemporary Stuhini-Lewes River arc grains, consistent with dissection of an active arc. Detrital rutile and muscovite data show rapid cooling and exhumation of metamorphic rocks during the Early Jurassic. Thermochronological data indicate that basin thermal evolution was domainal, with at least five regional temperature-time histories.
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Simandl, G. J., R. J. D'Souza, S. Paradis et J. Spence. Rare-earth element content of carbonate minerals in sediment-hosted Pb-Zn deposits, southern Canadian Rocky Mountains. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/328001.

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Paleozoic platform carbonate rocks of the Rocky Mountains host Mississippi Valley-type (MVT), magnesite, barite, and REE-barite-fluorite deposits. Farther west, platform carbonate rocks of the Kootenay Arc host MVT and fracture-controlled replacement (FCR) deposits. This is the first systematic LA-ICP-MS study of carbonates in MVT and FCR deposits. We investigated seven MVT deposits in the Rocky Mountains, and five MVT deposits in the Kootenay Arc. None of the post-Archean Australian shale (PAAS)-normalized REE profiles show light REE (LREE) depletion and strong negative Ce anomalies characteristic of modern seawater: some profiles are nearly flat; others show depletion in LREE similar to seawater but without negative Ce anomalies; others are middle REE enriched. Carbonates with a strong positive Eu anomaly precipitated from or interacted with different fluids than carbonates with flatter profiles without a strong positive Eu anomaly. REE signatures reflect crystallization conditions of primary carbonates, and crystallization and re-equilibration conditions of carbonates with ambient fluids during diagenesis, deep burial, and/or metamorphic recrystallization. Chemical evolution of fluids along their migration path, fluid-to-rock ratio, fluid acidity, redox, and temperature also influence REE profile shape, which helps establish genetic and timing constraints on studied deposits and improves knowledge of the metallogeny of the Kootenay Arc and Rocky Mountains.
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Ernst, W. G. Fluid flow, element migration, and petrotectonic evolution of the early Mesozoic Central Klamath island arc, northwesternmost California. Office of Scientific and Technical Information (OSTI), juin 1991. http://dx.doi.org/10.2172/6033634.

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Ernst, W. G. Fluid flow, element migration, and petrotectonic evolution of the Early Mesozoic central Klamath Island arc, northwesternmost California. Progress report. Office of Scientific and Technical Information (OSTI), décembre 1992. http://dx.doi.org/10.2172/171252.

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Johannson, G. G., et V. J. McNicoll. New U-Pb data from the Laberge Group, northwest British Columbia : implications for Stikinian arc evolution and Lower Jurassic time scale calibrations. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1997. http://dx.doi.org/10.4095/209098.

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Ernst, W. G. Fluid flow, element migration, and petrotectonic evolution of the early Mesozoic Central Klamath island arc, northwesternmost California. Progress report, September 15, 1990--September 14, 1991. Office of Scientific and Technical Information (OSTI), juin 1991. http://dx.doi.org/10.2172/10104952.

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