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In this paper we present a case history of seismic reservoir characterization where we estimate the probability of facies from seismic data and simulate a set of reservoir models honouring seismically‐derived probabilistic information. In appraisal and development phases, seismic data have a key role in reservoir characterization and static reservoir modelling, as in most of the cases seismic data are the only information available far away from the wells. However seismic data do not provide any direct measurements of reservoir properties, which have then to be estimated as a solution of a joint inverse problem. For this reason, we show the application of a complete workflow for static reservoir modelling where seismic data are integrated to derive probability volumes of facies and reservoir properties to condition reservoir geostatistical simulations. The studied case is a clastic reservoir in the Barents Sea, where a complete data set of well logs from five wells and a set of partial‐stacked seismic data are available. The multi‐property workflow is based on seismic inversion, petrophysics and rock physics modelling. In particular, log‐facies are defined on the basis of sedimentological information, petrophysical properties and also their elastic response. The link between petrophysical and elastic attributes is preserved by introducing a rock‐physics model in the inversion methodology. Finally, the uncertainty in the reservoir model is represented by multiple geostatistical realizations. The main result of this workflow is a set of facies realizations and associated rock properties that honour, within a fixed tolerance, seismic and well log data and assess the uncertainty associated with reservoir modelling.  相似文献   
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Accurate estimates of seasonal evapotranspiration (ET) at different temporal and spatial scales are essential for understanding the biological and environmental determinants of ecosystem water balance in arid regions and the patterns of water utilization by the vegetation. For this purpose, remote sensing ET estimates of a Patagonian desert in Southern Argentina were verified with field measurements of soil evaporation and plant transpiration using an open top chamber. Root distribution and seasonal variation in soil volumetric water content were also analysed. There was a high correlation between remote sensing and field measurements of ecosystem water fluxes. A substantial amount of the annual ET occurred in spring and early summer (73.4 mm) using winter rain stored in the soil profile and resulting in water content depletion of the upper soil layers. A smaller amount of annual ET was derived from few rainfall events occurring during the mid or late summer (41.4 mm). According to remote sensing, the 92.9% of the mean annual precipitation returns to the atmosphere by transpiration or evaporation from the bare soil and by canopy interception. Only 7.1% infiltrates to soil layers deeper than 200 cm contributing to the water table recharge. Fourier time series analysis, cross‐correlation methods and multiple linear regression models were used to analyse 11 years of remote sensing data to assess determinants of water fluxes. A linear model predicts well the variables that drive complex ecosystem processes such as ET. Leaf area index and air temperature were not linearly correlated to ET because of the multiple interaction among variables resulting in time lags with ET variations and thus these two variables were not included in the linear model. Soil water content, the fraction of photosynthetic active radiation and precipitation explained 86% of the ET monthly variations. The high volumetric water content and the small seasonal variations at 200‐cm depth were probably the result of little water uptake from deeper soil horizons by roots with low hydraulic conductivity. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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An analysis and discussion of the main features and effects of the 1999global seismicity based especially on the inferred patterns of strong(Mw 7) earthquakes using NEIC/USGS data is presented.Based on the above data and their statistical features (see also Table 1)one may state that from the point of view of occurrence rate (number/yr)the 1999 global seismicity was fairly regular, but from the moment (orenergy) release standpoint it is well under the long-term average. The spacepartition was again rather typical and time distribution was quasi-Poissonian,noteworthy, the 1999 worldwide seismicity had an anomalously high deathtoll, to be discussed later. Two main new insights are brought by ouranalysis: (i) a (mega)quiescence along the whole south American segmentof circum-Pacific earthquake belt, which was inferred and rated asanomalous while it was underway and which, in retrospect, ended with thegreat (Mw = 8.4 HRV) 2001 Arequipa (Peru) event; (ii) an intriguingmonotonous rate decrease within only magnitude class 5.0 to 5.9 duringthe analyzed period (i.e., 1990–1999).  相似文献   
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We study correlations amongst tidal fields originated by the large-scale distribution of matter in the Universe. The two-point tidal correlation is described as a rank-4 tensor, the elements of which can be written in terms of four fundamental scalar functions ranging, with respect to the spatial separation, from purely transversal to purely longitudinal correlations. Tidal fields, on both galaxy and cluster scales, are revealed to be correlated over distances larger than the mass–density correlation length, although traceless tidal fields show anti-correlation between diagonal terms along orthogonal directions. The cross-correlation between mass and tidal field is also analysed. These results are relevant for galaxy formation and the interpretation of large-scale weak lensing phenomena.  相似文献   
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The Capané ophiolite is a fragment of oceanic lithosphere obducted into the Ediacaran Porongos fold and thrust belt, southern Brasiliano Orogen. A studied rodingite blackwall contained in serpentinite has metasomatic zircon that displays multiple U–Pb ages from Tonian to Cryogenian (793 ± 0.9, 757 ± 2.1, 715 ± 2.2 Ma). The ages are interpreted as corresponding to multiple alteration events in the mantle. Multiple U–Pb–Hf isotopes and trace element analyses on the same crystals by laser ablation were controlled by backscatered electron images. Hf isotopes indicate zircon origin from a depleted mantle (εHf = +15 to +10.7), and trace elements point to an oceanic origin. The Capané ophiolite thus marks the evolution of the Adamastor ocean during the Tonian and Cryogenian, a significant result for the reconstruction of Rodinia and Gondwana supercontinents.  相似文献   
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ABSTRACT

We discuss the claim that the Amazon River has been subjected to a noticeable increase in suspended sediment transport (SST) in response to both climate and land-use changes. To study this, both satellite imagery and in situ data were compiled to produce a 32-year time series (1984–2016) of suspended sediment concentration. Both parametric and nonparametric statistics were applied to examine the SST time trend. The results indicate that there has been no statistically significant increase in SST in the last 32 years, independent of the statistical approach. The results indicate that, over the last 32 years at the Óbidos station, in Brazil, a recurring pattern of increase and decrease in SST has occurred, rather than a unidirectional systematic trend. This further explains the increasing trend reported in the literature and indicates that short time series are not recommended for time trend analyses due to the large inter-annual variability.  相似文献   
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The site of Pauli Stincus is located near the town of Terralba, on the inland shores of the Gulf of Oristano in west central Sardinia, Italy, and was occupied between the mid‐4th and the late 2nd century B.C. The site and its surroundings were the object of a joint archaeopedological and geomorphological study, which complemented the data from archaeological excavations. This study allowed us to evaluate the suitability of the different landscape and soil components for crop production in the Punic period. The discovery of a buried plow soil at the site's edge enabled us to identify a set of agricultural practices carried out by Punic farmers. These included the removal of sandy topsoil to cultivate deeper horizons enriched in illuvial clay, the use of a "sodbuster" or "rip ard," and the periodic burning of weeds, stubble, and other harvesting residues. The present study helped us to better understand the formation processes of the archaeological record at Pauli Stincus. Large quantities of allochtonous calcareous material were imported to the site from wet areas closer to the coast in order to produce earth‐based construction material, such as bricks and daub. © 2013 Wiley Periodicals, Inc.  相似文献   
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