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Basin scale, high-resolution 3D facies modeling of tectonically-confined turbidites: An example from the Firenzuola System (Marnoso-arenacea Formation, northern Apennines, Italy)
No full textFacies modeling is an important step in reservoir characterization, because each facies is related to specific petrophysical properties, and the assessment of their spatial arrangement is key for hydrocarbon recovery estimations. Most datasets related to subsurface sedimentary basins in exploration areas are limited to seismic resolution, which is lower than the actual thickness range of the beds in most depositional systems. In that way, detailed studies carried out in the outcropping area of collisional margins can be used as analogs of subsurface reservoirs with similar geologic settings in order to better predict heterogeneities and properties distribution, with no limitation of resolution. This study provides an experimental 3D high-resolution facies model based on 5,500m (about 18,000ft) of bed-by-bed measurements divided into seven stratigraphic logs, collected over several years of field studies in the Marnoso-arenacea Formation (MAF, northern Apennines, Italy). It focuses on the upper Serravallian Firenzuola turbidite system, which was deposited in a highly confined inner foredeep during an important phase of growth and propagation of the Monte Castellaccio thrust and Verghereto high. The syn-sedimentary activity of these tectonic structures deeply affected sediment dispersal patterns and facies distribution of the inner foredeep that became, in the final narrowing phase, a piggyback-type basin and induced the coeval shift of the main depositional area to an outer and relatively wider basin representing the new depocenter of the MAF foredeep. The modeling has provided quantitative analysis of turbidite facies trends and a numerical dataset suitable for further geostatistical and petrophysical studies
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
SEDIMENTOLOGICAL ANALYSIS AND STATISTICAL ELABORATION OF THE FACIES DISTRIBUTION IN A NORIAN BASINAL CALCAREOUS SUCCESSION (ZORZINO LIMESTONE, SOUTHERN ALPS, ITALY).
No full textStatistical analysis on the bed-thickness and facies distributions have been carried out on a Norian calcareous basinal succession (Zorzino Limestone, up to 1000 m thick) fed by a fault-controlled Norian T factory (Dolomia Principale), in the central Southern Alps (Lombardy, Northern Italy).
Four stratigraphic logs (Val Taleggio, Val Bracca, Val Cavallina and Iseo Lake sections), corresponding to a total thickness of approximately 1100 m and located in different parts of the basin (from the slope to the more distal depocentral zone) have been measured bed by bed. The studied sections stratigraphically belong to the upper part of the Zorzino Limestone, close to the boundary with the Riva di Solto Shale.
Sedimentological analysis allowed establishing seven main lithofacies categories in the Norian basinal sediments of the Zorzino Limestone, according to grain size (from carbonate mudstones to microconglomerates), composition of sediments, sedimentary structures (presence of grading, type of laminations, erosional bases, tractive features, bottom structures and bioturbation) and microscopic analysis. A lithofacies can represent an entire single bed (that is defined in this way by one lithofacies) or a homogeneous portion of it. The identified lithofacies are: Matrix supported breccias (1), Calcarenite supported breccias (2), Massive non-graded calcarenites (3), Massive graded calcarenites (4), Laminated graded calcarenites (5), Massive calcisiltites (6) and Calcilutites (7).
Each bed (one depositional event, sensu Campbell, 1967) or a group of beds with the same internal lithofacies architectures is referred to a single facies. More than 4000 beds have been measured in the resedimented Zorzino Limestone deposits, allowing to recognize eleven facies that have been classified using a specific letter code as follows: Matrix-supported breccias (Br1), Calcarenites supported breccias (Br2), Homogenous calcarenites (Rd), Cobbles to fine graded calcarenites (Cl1), Coarse-medium to fine graded calcarenites (Cl2), Laminated medium to fine graded calcarenites (Cl3), Laminated fine to very fine graded calcarenites (Cl4), Thin bedded graded calcarenites (Cl5), Homogeneous calcisiltites (M1), Laminated calcisiltites (M2) and Dark-gray laminites (LS). The eleven facies characterizing the Zorzino Limestone are the expression of three main depositional processes; these are: 1) Freezing from cohesive flows (mud debris flows, sandy debris flows and silty-mud debris flows), 2) deposition from turbulent flows (high-density turbidity currents and low-density turbidity currents) and 3) grain-by-grain settling from mud suspension during periods of low sedimentation rate. Chaotic bodies and slump deposits are the product of gravity-driven resedimentation.
The facies distribution analysis shows that the calcarenitic facies (Br2, Rd, Cl1, Cl2, Cl3, Cl4 and Cl5) prevail in the slope settings, whereas the calcisiltitic facies (M1 and M2) in the basinal settings, suggesting that facies distribution is strongly related to paleogeography.
The microfacies analysis of the several lithofacies highlights that two kinds of components characterize the resedimented deposits of the Zorzino Limestone: bioclastic components and intraclastic components originated by the disruption of the facies Ls and/or constituted by clear-light gray micrites from the top of the platform. Based on the distinction between these components and on their different quantitative distribution in the lithofacies, different typologies of deposits have been recognized: (1) predominantly bioclastic (Cl2, Cl3, Cl4 and Cl5 in the slope settings); (2) deposits characterized by a variable proportion between bioclasts and intraclsts (Br2, Rd, Cl1 Cl2, Cl3, Cl4 and Cl5 in the slope settings); and (3) predominantly intraclastic (facies M1, M2, Cl2 and Cl4 in the basinal settings).
The type of bioclasts indicates an origin of the sediments from the top of the platform for the resedimented deposits of the slope, whereas the composition of the intraclasts indicates an origin from the slope for the calcarenites of the depocentral area.
The facies and their related thicknesses have been used to perform statistical analysis. The transitional frequency analysis and the bed thickness distribution analysis were selected in order to evaluate analogies and differences between the facies and the possible geological implications.
The Markov chain analysis has been applied on the marginal successions, where a higher variability of facies is present. This analysis shows the absence of cyclic patterns in the successions suggesting that the vertical occurrence of facies is connected to processes acting randomly on the slope.
A bed thickness distribution analysis for the calcarenitic and calcisiltitic beds has been performed for each of the measured series in each depositional setting in order to recognize the possible changes in their distribution across the basin. Data have been processed both on the total population and on the single facies grouped according to the grain size. The identification of the kind of distribution allows proposing hypothesis on the triggering processes controlling the sedimentation in the basin; the log-log exceedence plots as well as linear histogram values highlighted that the bed thickness distribution follows a gamma and/or exponential model suggesting a non-fractal property (no power law distribution). The gamma/exponential distributions describe populations of events that are independent from each other and can be related to different triggering mechanisms operating both on the slope and along the margin that are affected by different factors of control (earthquakes, sea level changes etc.).
The observations based on the sedimentological analysis and on the statistics suggest that different source areas and depositional processes were distributed in the basin where the Zorzino Limestone was deposited, evidencing differences in composition and facies distribution from slope to the depocentre
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