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Multidisciplinary characterization of diapiric basins integrating field examples, numerical and analogue modelling: Central High Atlas Basin (Morocco)
Get PDFThe complexity of the interplay between tectonics and sedimentation increases when salt tectonics is involved because of the ductility of salt and its ability to flow. Discrimination between extensional tectonics and salt-related processes is problematic; especially where salt-related rift basins were inverted as occurred in the Central High Atlas in Morocco.
The aim of the present work was to analyse and understand the dynamics of the Central High Atlas diapiric basin during the Early Jurassic rift and subsequent post-rift periods using a multidisciplinary workflow integrating fieldwork, analogue models and subsidence and thermal numerical modelling. Two regions were examined to assess the effects of salt tectonics in the evolution of the basin; the Djebel Bou Dahar platform-basin system represented the fault domain of the rift basin where diapiric activity was not described and the Tazoult-Amezraï area and Imilchil diapiric province corresponding to the unstable domain of the basin characterised by the presence of diapiric salt ridges and minibasins.
Results from analogue models highlighted the intrinsic interrelation between extension, diapirism and sedimentation that characterised the diapiric domain of the Central High Atlas. Longitudinal and transverse sedimentary progradations and their timing had a strong impact in the migration of ductile layers, in the growth of diapirs and in their lateral structural variations; triggering well-developed passive diapirs in the proximal domains and incipient reactive diapirs or poorly developed roller-like and passive diapirs in the distal domains of the sediment source. Analogue models including post-diapiric compression fairly reproduced the observed structure in the studied areas. Modelling with 6% and 10% of shortening, slightly lower than the Atlas one, produced the progressive close-up of the two flanks of salt walls and their final welding as well as the steepening of their outward flanks, with dips increasing from 8o-17o prior to compression to 30o-50o after compression.
Subsidence curves varied depending on the analysed localities of the rift basin. Djebel Bou Dahar showed long-term and low-rate tectonic and total subsidence (0.06 and 0.08 mm yr-1, respectively). The roughly parallel evolution of both total and tectonic subsidence curves indicates the main extensional tectonic influence on subsidence pattern, as corroborated by the syndepositional activity of the outcropping Sinemurian-Pliensbachian normal faults. In the unstable domain, Amezraï minibasin centre showed tectonic and total subsidence rates between 0.06-0.32 and 0.19-0.98 mm yr-1, rates one order of magnitude higher than in the Djebel Bou Dahar. These subsidence rates were up to two-fold their equivalent rates in the Tazoult salt wall (0.01-0.27 and 0.09-0.74 mm yr-1). In the Imilchil diapiric province lateral shifts of the main subsiding depocenters were recorded during Toarcian to Callovian times (tectonic and total subsidence rates up to 0.23 and 0.90 mm yr-1). The subsidence of the unstable domain was caused by the combination of normal fault extension and salt withdrawal from beneath the minibasins during rifting, being the salt-related subsidence predominant during the post-rift and masking the expected subsidence pattern for a rift-post rift transition.
For the first time, 27 new vitrinite reflectance data were used to build the thermal evolution and associated geohistory of the Central High Atlas. Thermal models, with heat flows of 105 mW/m2 (from 189 to 140 Ma) followed by 60 mW/m2 and 70 mW/m2 (from 189 to 182.7 Ma) followed by 60 mW/m2, pointed to a post-Middle Jurassic evolution characterised by long-term and low-rate subsidence and an overburden between 1200-2400 m on the Tazoult-Amezraï area.
The comparison of subsidence curves from this study with Saharan Atlas and Tunisian Atlas showed that peak of subsidence in these salt-related domains became younger to the east.La discriminació entre processos associats a tectònica extensiva i a tectònica salina es problemàtica; especialment en conques diapíriques extensives invertides com és el cas del Alt Atles Central de Marroc (CHA). L’objectiu d’aquesta tesis és analitzar i entendre els processos que interaccionaren a la conca diapírica del CHA durant el rift Juràssic i el subseqüent període post rift, utilitzant una metodologia multidisciplinària que integra treball de camp, models analògics i models numèrics. S’han estudiat dos dominis de la conca: no diapiric i diapiric (diapirisme durant el Juràssic Inferior i Mitjà).
Els models analògics mostren que progradacions longitudinals i transversals i el moment quan s’inicien tenen un gran impacte en la migració dels nivells dúctils, en el mode de creixement diapiric i les seves variacions laterals. Els models amb compressió post-diapírica mostren que dita compressió produeix la reducció progressiva de l’amplada de les estructures diapíriques fins al seu tancament complet, així com a un increment dels cabussaments dels flancs com s’ha observat a les zones d’estudi.
Les corbes de subsidència varien segons el domini analitzat. El domini no diapiric es caracteritza per un període llarg de baixes taxes de subsidència tectònica i total (0.06 i 0.08 mma-1). El domini diapiric registra taxes de subsidència tectònica i total fins a un ordre de magnitud majors que en el domini no diapiric (0.23 i 0.90 mma-1) i una migració dels depocentres subsidents. La subsidència del domini diapiric s’interpreta, durant el rift Juràssic Inferior, com una combinació d’activitat de falles normals i migració salina, sent aquesta darrera la predominant durant la fase post-extensiva i emmascarant el patró de subsidència esperat en un estadi de transició rift-post rift.
Per primera vegada, es presenta la geohistòria de la part central del CHA. Els models tèrmics emprats per a la seva construcció, avaluats amb 27 noves dades de reflectància de vitrinites de la zona d’estudi, suggereixen una evolució post-Juràssic Mitjà caracteritzada per un període llarg de baixa subsidència que hauria enterrat la regió entre 1200-2400 m, en comptes de una complexa historia que inclouria diversos esdeveniments d’exhumació com s’ha enregistrat en altres zones del Alt Atles Marroquí
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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