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Talc Formation Along Continental Low-Angle Normal Faults:Growth, Deformation, and Mechanical Consequences
No full textShear zone folds: records of flow perturbations or structural inheritance?
No full textDeformation within shear zones can be both temporally and spatially variable, resulting in multiple generations of folds which display a range of scales and overprinting relationships in mylonitic rocks associated with high strain zones. Despite such complexities, two main fold associations are broadly recognized in many shear zone settings: early tight to isoclinal sheath folds, often with mylonitic limbs that are post-dated by one or more local generations of synshearing folds which are preserved within, or root downwards into mylonitic high strain zones. These latter structures locally fold the mylonitic foliation and lineation whilst displaying geometric characteristics that are kinematically compatible with the movement regime of the major shear zone. Using examples related to ductile thrusting in Moine metasediments of north Scotland, we show that both types of fold display predictable geometric patterns on fabric topology plots. Fold axes and axial surfaces display consistent changes in asymmetry and sense of obliquity relative to local, transport-parallel mineral lineations that can be used to map out a series of culminations and depression zones. The sheath folds preserve more acute, but almost identical geometric patterns compared to the later synshearing folds, with culmination and depression zones often coinciding in location and scale. Detailed analysis also demonstrates that the distribution of finite strain is systematically linked to the architecture of all folds and that clear and predictable relationships exist between the fabric topologies of both the sheath folds and synshearing folds. These consistent topological relationships could be explained in terms of a fold evolution model, where sheath folds represent a more highly deformed and evolved variety of synshearing folds originally generated during perturbations in ductile flow. However, an alternative fold inheritance model predicts that the gross structural architecture generated during sheath folding may subsequently control the geometry and govern the orientation of the synshearing folds. Both models may be widely applicable in a broad range of shear zorie environments.</p
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
Structural and petrological features of a Late Hercynian shear zone in the Calabrian middle crust (southern Italy)
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Constraints on fault dynamic weakening mechanisms from natural slip surfaces in carbonate faults
No full textVariations 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
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