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Neogene-Quaternary evolution of the Central Apennine thrust front: Constraints from sequence and forward balancing of a regional cross-section/Evoluzione neogenico-quaternaria del fronte della catena centro-appenninica: vincoli dal bilanciamento di una sezione geologica regionale
No full textIn this study the outer sector of the Central Apennine of Italy
and the adjacent Adriatic foreland were analysed in order to reconstruct their structural setting and the Neogene-Quaternary evolution of the fold-and-thrust belt.
In the investigated area the thrust front is largely buried
beneath Messinian-Pliocene siliciclastic sediments in the on-shore sector (i.e. peri-Adriatic Basin), and by Pliocene-Quaternary deposits in the adjacent Adriatic Basin (BALLY et alii, 1986; ORI et alii, 1991; CASNEDI & SERAFINI, 1994; ARTONI & CASERO, 1997; MONTEFALCONE,
2000; ARGNANI et alii, 2001; CALAMITA et alii, 2002; BOLIS et alii, 2003). In the inner sector of the chain the Mesozoic-Paleogene carbonate units crop out in the core of two anticlines (the Acquasanta and the M.gna dei Fiori Structures – KOOPMAN, 1983; MATTEI, 1987; CALAMITA et alii, 1991; CENTAMORE et alii, 1992a; INVERNIZZI
& RIDOLFI, 1992; MARSILI & TOZZI, 1995; CALAMITA et alii, 1998); by contrast the top of the carbonate succession abruptly deepens toward the east where it lies at depths of more than 7000 meters below sea level. Here, the thick Pliocene-Quaternary siliciclastic succession is involved in an imbricate thin-skinned fold-and-thrust system with a leading edge located in the Central Adriatic Basin.
A balanced geological cross-section based on surface geologicalstructural surveys and subsurface data (i.e. seismic reflection profiles and well-log data) was constructed with the aim to illustrate the structural setting of the outer sector of the Central Apennines of Italy. This cross-section extends through the Acquasanta anticline, the M.gna dei Fiori anticline, the peri-Adriatic Basin and the Central
Adriatic off-shore, as far as the Italy-Croatia mid-line. The section allowed us to define the geometry of the Central Apennine thrust front, the foreland ramp, and the syn-tectonic basin infill; moreover, by sequential balancing and subsequent forward balancing, the tectonic evolution of the chain-foredeep-foreland system were reconstructed
and the shortening rates were calculated.
Based on this study, the complex structural setting of the Central Apennine fold-and-thrust belt results from the interaction between an extremely thin-skinned and a thick-skinned thrust system.
The former only affects the syn-orogenic siliciclastic deposits
and generally predates the deeper thrust system that cuts across the whole sedimentary cover (i.e. carbonate units and overlying siliciclastic sediments), and locally the basement. The uncoupling between thin and thick-skinned tectonics strictly controls the evolution and migration of the syn-tectonic basins, and influences the sequence of thrust propagation; this latter, with respect to the deeper stratigraphic levels, is mainly toward the foreland. Moreover,
spacing and location of thrust ramps are controlled by pre-existing discontinuities that affected the foreland ramp
The distributional divergence of horizontal vector fields vanishing at infinity on Carnot groups
Full text linkWe define a BV -type space in the setting of Carnot groups (i.e., simply
connected Lie groups with stratified nilpotent Lie algebra) that allows one to
characterize all distributions F for which there exists a continuous horizontal
vector field {\Phi}, vanishing at infinity, that solves the equation divH{\Phi}
= F. This generalize to the setting of Carnot groups some results by De Pauw
and Pfeffer, [12], and by De Pauw and Torres, [13], for the Euclidean setting.Comment: 24 page
Gaffney–Friedrichs inequality for differential forms on Heisenberg groups
Full text linkIn this paper, we will prove several generalized versions, dependent on different boundary conditions, of the classical Gaffney–Friedrichs inequality for differential forms on Heisenberg groups. In the first part of the paper, we will consider horizontal differential forms and the horizontal differential. In the second part, we shall prove the counterpart of these results in the context of Rumin’s complex
CMC Spheres in the Heisenberg Group
Full text linkWe study a family of spheres with constant mean curvature (CMC) in the Riemannian Heisenberg group H1. These spheres are conjectured to be the isoperimetric sets of H1. We prove several results supporting this conjecture. We also focus our attention on the sub-Riemannian limit
Un risultato di densità in uno spazio di tipo BV in gruppi di Carnot
Full text linkIn the setting of Carnot groups (connected, simply connected and stratified Lie groups), we prove a density result for a BV-type space previously introduced in [3]. In addition, we relate the dual of this BV-type space with the dual of the well known space of functions of intrinsic bounded variation. These results extend to the setting of Carnot groups some properties studied by Phuc e Torres in [22] and [23] in the Euclidean setting.Si prova un risultato di densità per uno spazio di tipo BV nell'ambito dei gruppi di Carnot (gruppi di Lie connessi, semplicemente connessi e stratificati) già introdotto in [3]. Come conseguenza di questo risultato di densità si mettono in relazione lo spazio delle funzioni a variazione (intrinseca) limitata con il duale di questo spazio. Questi risultati estendono al caso dei gruppi di Carnot alcune proprietà studiate in ambito euclideo da Phuc e Torres in [22] and [23]
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
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