632 research outputs found

    Hybrid Event Beds Generated By Local Substrate Delamination On A Confined-Basin Floor

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    The outer parts of deep-water fans, and the basin plains into which they pass, are often described as areas where erosion is negligible and turbidite systems have net aggradation. Nevertheless sedimentological and stratigraphic analysis of outer fan lobe and confined basin plain deposits in Cretaceous-Paleocene Gottero Sandstone (NW of Italy) has revealed extensive but cryptic bedding-parallel substrate-delamination features at the base of many sheet-like event beds. These comprise a variety of shallow but wide scour structures showing evidence of lateral expansion by sand-injection. The scours commonly occur at the base of beds made up of a basal clean sandstone overlain by argillaceous sandstone containing abundant mudstone clasts and locally large substrate rafts (up to 20 meters long). These strata are interpreted as a type of hybrid event bed. Field observations suggest that mud-clast entrainment occurred by delamination at the base of dense sandy flows. The large rafts, in some cases only partly detached, were incorporated in the flows locally and then carried for short distances (100s m to a few km) before partly disaggregating and undergoing deformation due to internal shearing. The development of such features may be common in flat and/or confined basin settings where high-volume flows interact with a cohesive and well layered substrate (e.g. muddy outer fans or confined or ponded basins with thick mudstone caps). Delamination is therefore suggested as an alternative mechanism leading to the formation of hybrid event beds following local substrate entrainment on the basin floor as opposed to on more remote slopes and at channel-lobe transition zones

    The way to ultrafast, high-throughput enantioseparations of bioactive compounds in liquid and supercritical fluid chromatography

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    Until less than 10 years ago, chiral separations were carried out with columns packed with 5 or 3 μm fully porous particles (FPPs). Times to resolve enantiomeric mixtures were easily larger than 30 min, or so. Pushed especially by stringent requirements from medicinal and pharmaceutical industries, during the last years the field of chiral separations by liquid chromatography has undergone what can be defined a “true revolution”. With the purpose of developing ever faster and efficient method of separations, indeed, very efficient particle formats, such as superficially porous particles (SPPs) or sub-2 μm FPPs, have been functionalized with chiral selectors and employed in ultrafast applications. Thanks to the use of short column (1–2 cm long), packed with these extremely efficient chiral stationary phases (CSPs), operated at very high flow rates (5–8 mL/min), resolution of racemates could be accomplished in very short time, in many cases less than 1 s in normal-, reversed-phase and HILIC conditions. These CSPs have been found to be particularly promising also to carry out high-throughput separations under supercritical fluid chromatography (SFC) conditions. The most important results that have been recently achieved in terms of ultrafast, high-throughput enantioseparations both in liquid and supercritical fluid chromatography with particular attention to the very important field of bioactive chiral compounds will be reviewed in this manuscript. Attention will be focused not only on the latest introduced CSPs and their applications, but also on instrumental modifications which are required in some cases in order to fully exploit the intrinsic potential of new generation chiral columns

    A test of analog-based tools for quantitative prediction of large-scale fluvial architecture

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    Outcrop analogs are routinely used to constrain models of subsurface fluvial sedimentary architecture built through stochastic modeling or inter-well sandbody correlations. Correlability models are analog-based quantitative templates for guiding the well-to-well correlation of sand-bodies, whereas indicator variograms used as input to reservoir models can be parameterized from data collected from analogs, using existing empirical relationships. This study tests the value and limitations of adopting analog-informed correlability models and indicator-variogram models, and assesses the impact and significance of analog choice in subsurface workflows for characterizing fluvial reservoirs. A 3.2 km long architectural panel based on a Virtual Outcrop from the Cretaceous Blackhawk Formation (Wasatch Plateau, Utah, USA) has been used to test the methodologies: vertical 'dummy' wells have been constructed across the panel, and the intervening fluvial architecture has been predicted using correlability models and sequential indicator simulations. The correlability and indicator-variogram models employed to predict the outcrop architecture have been compiled using information drawn from an architectural database. These models relate to: (i) analogs that partially match with the Blackhawk Formation in terms of depositional setting, and (ii) empirical relationships relating statistics on depositional-element geometries and spatial relations to net-to-gross ratio, based on data from multiple fluvial systems of a variety of forms. The forecasting methods are assessed by quantifying the mismatch between predicted architecture and outcrop observations in terms of the correlability of channel complexes and static connectivity of channel deposits. Results highlight the effectiveness of correlability models as a check for the geologic realism of correlation panels, and the value of analog-informed indicator variograms as a valid alternative to variogram-model parameterization through geostatistical analysis of well data. This work has application in the definition of best-practice use of analogs in subsurface workflows; it provides insight into the typical degree of realism of analog-based predictions of reservoir architecture, as well as on the impact of analog choice, and draws attention to associated pitfalls

    Influence of flow containment and substrate entrainment upon sandy hybrid event beds containing a co-genetic mud-clast-rich division

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    Individual sandstone beds containing a co-genetic mud-clast-rich (MCR) division are being increasingly described from the distal reaches of many deep-water fan systems. These deposits, termed hybrid event beds, are considered to record a flow whose composition and rheology changed significantly to become increasingly more argillaceous (clay-rich), MCR and turbulence-suppressed during the deposition of a single event bed. Studies of confined systems, in which gravity flows were affected by confining sea-floor topography, have documented similar deposits recording turbulence suppression in proximity to confining sea-floor topography (e.g., basin margins). In new research from a confined, contained system from the Castagnola Basin of NW Italy, lateral transects of individual sandstone beds 5 km in extent show that individual sandstone beds contain a co-genetic MCR division which is often; 1) extensive across the basin rather than localised adjacent to confining topography; 2) exhibits rapid, significant and repeated variation in depositional character over short length scales (tens to hundreds of metres), specifically in terms of the thickness of co-genetic MCR divisions and the size and abundance of clasts contained within them; and 3) exhibits variation in depositional character over larger length scales (> 1 km) which is non-systematic in relation to palaeoflow direction or increasing proximity towards the counter slope of the downstream confining northern basin margin. A suite of factors within the Castagnola Basin is thought to have resulted in the deposition of these co-genetic MCR divisions whose thickness and distribution are less predictable in relation to confining sea-floor topography than those described from other confined uncontained settings. Specific factors include; 1) recent and voluminous entrainment of muddy substrate at seemingly random locations across the basin floor and their support and transport within a high sediment concentration gravity flow; and 2) containment (ponding) of gravity flows within a confined basin, which is thought to have established extensive and complex three dimensional flow dynamics across the basin following flow interaction with multiple basin margins. This research highlights the role of entrainment of muddy substrate and subsequent transport processes of muddy substrate for developing co-genetic MCR divisions, as well as the importance of understanding the degree of containment depositional systems experienced when considering the spatial distribution of depositional facies, and thus reservoir quality, in topographically complex settings

    Is endurantism really more plausible than perdurantism from a common-sense perspective?

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    En este artículo discutiré tres de los principales argumentos a favor de que los objetos persisten al tener partes temporales ubicadas en diferentes momentos. A este punto de vista se ha denominado perdurantismo. En la primera sección, presentaré dos teorías rivales de la persistencia, el perdurantismo y el endurantismo. A continuación discutiré tres argumentos a favor del perdurantismo: el argumento a partir de los intrínsecos temporales, el argumento de la vaguedad y el argumento de la relatividad especial. Concluiré que ninguno de estos argumentos es conclusivo a favor del perdurantismo, pero mostraré que el endurantismo enfrenta dificultades importantes para ofrecer sus soluciones a los problemas relevantes, y que las soluciones propuestas son a menudo en desacuerdo con el sentido común. En consecuencia, si uno de los principales problemas para el perdurantismo radica en su desacuerdo con el sentido común, el endurantismo no está en una mejor posición.I will discuss three arguments in favor of perdurantism, the thesis that objects persist by having temporal parts located at different times. Firstly, I will introduce the rival accounts of persistence of perdurantism and endurantism. Then I will discuss three arguments for perdurantism: the problem of temporary intrinsics, the argument from vagueness and the argument from Special Relativity. I will conclude that none of them represents a knock-down argument for perdurantism. However, endurantism faces important difficulties in offering its solutions to the issues at stake, and the solutions proposed are often at odds with commonsense. Therefore, if one of the main problem for perdurantism is its being at odds with commonsense, endurantism is in no better position with respect to this issue

    Bioturbation beyond Earth: potential, methods and models of astroichnology

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    Traces – burrows, borings, footprints – are important evidences of biological behaviour on Earth, yet they received relatively little attention in the field of astrobiology. This study aims to discuss the application of ichnology (i.e. the study of life activity traces) to the search for past and modern life beyond Earth (i.e. herein called Astroichnology)

    Petrographic data from the Oligocene-lower Langhian succession of the Arquata Scrivia area in the Tertiary Piedmont Basin (NW Italy)

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    This petrographic database is a compilation made to study the Oligocene-Langhian succession of the Arquata Scrivia area, consisting of different shallow to deep-water marine sedimentary units deposited in the eastern Tertiary Piedmont Basin (NW Italy). This database is unique for the studied succession, which was not priorly investigated for the petrographic content of its component units.The samples were collected from lower, middle and upper parts of each sedimentary unit and analyzed for identifying their petrographic composition via qualitative and quantitative methods by means of polarized-light microscope. The collected petrographic data are presented within quartzfeldspar-lithic ternary plots.Even though these data are elementary analytical outputs, they represent the starting point for future analyses in order to understand the evolution of the basin on a larger scale.(c) 2022 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/

    Edge Cloud Computing for Geospatial Data Processing and Approximate Queries

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    Architecture for optimizing geospatial data processing pipelines in the cloud by making use of edge nodes deployed on containers in an urban moving taxi scenario (specifically Shenzhen, China). Edge nodes are using Geohash for efficient data preprocessing, including Geohash-based stratified sampling, and neighborhood location of incoming messages. Apache Kafka was then used to send data to a Spark cluster using a spatially-aware technique for data distribution. In particular, a Kafka topic for each neighborhood of the city considered was created, and each of these topics contained only messages originated in the same neighborhood

    What Autism Can Tell Us About the Link between Empathy and Moral Reasoning?

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    I will discuss the relationship between empathy and moral reasoning among people with autism. I will discuss the deficit that people with autism show in empathy, that affects mostly perspective taking, and the studies conducted by Blair (1996) and Moran et al. (2011), which suggest that people with autism are not significantly impaired in moral reasoning. I will argue that perspective taking might play an important role in moral reasoning. As Moran et al. found, unlike typically developed, people with autism do not judge accidental and attempted harms differently. I will suggest that their deficit in perspective taking might explain this difference. However, I will conclude, studies on autism do not help to assess the influence of the affective components of empathy on moral reasoning

    Short length-scale variability of hybrid event beds and its applied significance

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    Hybrid event beds (HEBs) are a type of deep-water sediment gravity flow deposit that generally comprise a basal clean sandstone overlain by a variety of muddier and less-permeable sandy facies. They are thought to be emplaced by combinations of turbidity currents, transitional flows and debris flows, all as part of the same transport event. To date, a number of studies have highlighted the common presence of HEBs mainly in the outer and marginal parts of deep-water systems where they replace beds composed dominantly of clean sand up-dip and/or axially over scales of km to 10s km. In addition to these broad patterns, important yet poorly understood short-length facies changes (over metres to 100s m) occur, modifying the overall texture and reservoir characteristics at or beneath typical spacing of production wells. The nature and origin of the short length-scale transitions is here addressed in four well-exposed HEB-prone outcrops: the Cretaceous-Paleocene Gottero Sandstone and the Miocene Cilento Flysch, both in Italy, the Carboniferous Mam Tor Sandstone in northern England, and the Carboniferous basal Ross Sandstone Formation, Western Ireland. A series of detailed correlation panels show marked lateral variations in internal bed make-up for most of the hybrid event beds studied. This variability typically involves lateral changes in the proportions of the cleaner basal sandstone and the overlying muddy sandstone division that occur without substantial change in the overall event bed thickness. The variability is inferred to reflect the complex fingering between the up-dip sandstone-dominated part of the event bed and the down-dip linked debrite due to internal erosion (ploughing) of the debrite into the basal clean sand. Where the upper part of the bed is dominated by large mudstone rafts, these may have foundered into liquefied sand and been injected and partly fragmented by the sand intrusions. The variable thickness and continuity of the basal clean sandstones have important implications for reservoir characterisation; significant variability in bed character at interwell scale can be anticipated. Rugose contacts between the intra-bed facies divisions may impact on drainage and sweep efficiency during hydrocarbon production
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