Preface to Special Edition of EM&P, Reporting on the INAF/Arcetri-ESO-Workshop on “Future Ground-based Solar System Research: Synergies with Space Probes and Space Telescope” held at Portoferraio, Elba, Italy, 8–12 September 2008     

Hans Ulrich Käufl  Gian Paolo Tozzi 《Earth, Moon, and Planets》2009,105(2-4):61-64

  相似文献   

Uncertainty quantification of overpressure buildup through inverse modeling of compaction processes in sedimentary basins     

Ivo Colombo  Giovanni M. Porta  Paolo Ruffo  Alberto Guadagnini 《Hydrogeology Journal》2017,25(2):385-403

This study illustrates a procedure conducive to a preliminary risk analysis of overpressure development in sedimentary basins characterized by alternating depositional events of sandstone and shale layers. The approach rests on two key elements: (1) forward modeling of fluid flow and compaction, and (2) application of a model-complexity reduction technique based on a generalized polynomial chaos expansion (gPCE). The forward model considers a one-dimensional vertical compaction processes. The gPCE model is then used in an inverse modeling context to obtain efficient model parameter estimation and uncertainty quantification. The methodology is applied to two field settings considered in previous literature works, i.e. the Venture Field (Scotian Shelf, Canada) and the Navarin Basin (Bering Sea, Alaska, USA), relying on available porosity and pressure information for model calibration. It is found that the best result is obtained when porosity and pressure data are considered jointly in the model calibration procedure. Uncertainty propagation from unknown input parameters to model outputs, such as pore pressure vertical distribution, is investigated and quantified. This modeling strategy enables one to quantify the relative importance of key phenomena governing the feedback between sediment compaction and fluid flow processes and driving the buildup of fluid overpressure in stratified sedimentary basins characterized by the presence of low-permeability layers. The results here illustrated (1) allow for diagnosis of the critical role played by the parameters of quantitative formulations linking porosity and permeability in compacted shales and (2) provide an explicit and detailed quantification of the effects of their uncertainty in field settings.  相似文献   

Solar radio pulsating structures during September 9, 2001 at meter wavelength     

Adolfo L. Méndez Berhondo  Ramón E. Rodríguez Taboada  Paolo Zlobec 《Astrophysics and Space Science》2008,318(1-2):73-78

Pulsating structures recorded at 237 MHz that are associated to decimetric continuum enhancement during the September 9, 2001 solar radio burst are described. We analyzed the radiopolarimetric data recorded at the Trieste Solar Radio System (INAF—Trieste Astronomical Observatory—Basovizza Observing Station) with very high time resolution (1 ms) at metric frequencies. Two different types of pulsations that occur in about 4 minutes at the same frequency are described. The possible mechanisms are analyzed and some parameters of the associated magnetic structure are estimated.  相似文献   

Humans and the Earth's surface          下载免费PDF全文

Paolo Tarolli 《地球表面变化过程与地形》2016,41(15):2301-2304

  相似文献   

Preface to the special issue “Strategic applications of real-time risk mitigation strategies and tools: case studies and lessons learned in REAKT”     

Carlo Cauzzi  Paolo Gasparini  Stefan Wiemer  Jochen Zschau 《Bulletin of Earthquake Engineering》2016,14(9):2437-2439

  相似文献   

Modeling the Permeability Loss of Metallic Iron Water Filtration Systems     

Sabine Caré  Richard Crane  Paolo S. Calabrò  Antoine Ghauch  Emile Temgoua  Chicgoua Noubactep 《洁净——土壤、空气、水》2013,41(3):275-282

Over the past 30 years the literature has burgeoned with in situ approaches for groundwater remediation. Of the methods currently available, the use of metallic iron (Fe⁰) in permeable reactive barrier (PRB) systems is one of the most commonly applied. Despite such interest, an increasing amount of experimental and field observations have reported inconsistent Fe⁰ barrier operation compared to contemporary theory. In the current work, a critical review of the physical chemistry of aqueous Fe⁰ corrosion in porous media is presented. Subsequent implications for the design of Fe⁰ filtration systems are modeled. The results suggest that: (i) for the pH range of natural waters (>4.5), the high volumetric expansion of Fe⁰ during oxidation and precipitation dictates that Fe⁰ should be mixed with a non‐expansive material; (ii) naturally occurring solute precipitates have a negligible impact on permeability loss compared to Fe⁰ expansive corrosion; and (iii) the proliferation of H₂ metabolizing bacteria may contribute to alleviate permeability loss. As a consequence, it is suggested that more emphasis must be placed on future work with regard to considering the Fe⁰ PRB system as a physical (size‐exclusion) water filter device.  相似文献   

Garnet and spinel in fertile and depleted mantle: insights from thermodynamic modelling   总被引：2，自引：1，他引：1  

Luca Ziberna  Stephan Klemme  Paolo Nimis 《Contributions to Mineralogy and Petrology》2013,166(2):411-421

We performed thermodynamic calculations based on model and natural peridotitic compositions at pressure and temperature conditions relevant to the Earth’s upper mantle, using well-established free energy minimization techniques. The model is consistent with the available experimental data in Cr-bearing peridotitic systems and can therefore be used to predict phase relations and mineral compositions in a wide range of realistic mantle compositions. The generated phase diagrams for six different bulk compositions, representative of fertile, depleted and ultra-depleted peridotitic mantle, shown that the garnet + spinel stability field is always broad at low temperatures and progressively narrows with increasing temperatures. In lithospheric sections with hot geotherms (ca. 60 mW/m²), garnet coexists with spinel across an interval of 10–15 km, at ca. 50–70 km depths. In colder, cratonic, lithospheric sections (e.g. along a 40 mW/m² geotherm), the width of the garnet–spinel transition strongly depends on bulk composition: In fertile mantle, spinel can coexist with garnet to about 120 km depth, while in an ultra-depleted harzburgitic mantle, it can be stable to over 180 km depth. The formation of chromian spinel inclusions in diamonds is restricted to pressures between 4.0 and 6.0 GPa. The modes of spinel decrease rapidly to less than 1 vol % when it coexists with garnet; hence, spinel grains can be easily overlooked during the petrographical characterization of small mantle xenoliths. The very Cr-rich nature of many spinels from xenoliths and diamonds from cratonic settings may be simply a consequence of their low modes in high-pressure assemblages; thus, their composition does not necessarily imply an extremely refractory composition of the source rock. The model also shows that large Ca and Cr variations in lherzolitic garnets in equilibrium with spinel can be explained by variations of pressure and temperature along a continental geotherm and do not necessarily imply variations of bulk composition. The slope of the Cr# [i.e. Cr/(Cr + Al)mol] isopleths in garnet in equilibrium with spinel changes significantly at high temperatures, posing serious limitations to the applicability of empirical geobarometric methods calibrated on cratonic mantle xenoliths in hotter, off-craton, lithospheric mantle sections.  相似文献   

Recent geomorphological changes of the middle and lower Calore River (Campania, Southern Italy)   总被引：1，自引：1，他引：0  

Paolo Magliulo  Alessio Valente  Elena Cartojan 《Environmental Earth Sciences》2013,70(6):2785-2805

The geomorphological changes experienced by the middle and lower Calore River (Southern Italy) between 1957 and 1998 were investigated. Data derived from field surveys and interpretation of topographic maps and aerial photos were introduced into a geographic information system (GIS) and processed. The results showed that the Calore River underwent a mean narrowing of 66 %, with a peak of 86 %. The channel length increased by approximately 75 m and the sinuosity from 1.311 to 1.314. The extension of fluvial bars reduced by more than 83 %, while their number increased from 151 to 381. Field evidence of riverbed lowering, such as river terraces formed in the considered time span and exhumation of foundations of bridges and flood-walls, were also constantly detected. Due to these channel adjustments, the Calore River morphology changed from transitional to single-thread. These results were coherent with those reported in the pre-existing literature about channel adjustments experienced by many rivers during the twentieth century. They all were explainable with a reduction of the bedload transport; this latter, in turn, is completely in accordance with the environmental changes that affected the Calore River system in the considered period (i.e., damming and/or channelization of the main tributaries, reduction of liquid discharge due to water withdrawals and sediment mining from the riverbed).  相似文献   

Effect of the dilution process on the attenuation of contaminants in aquifers   总被引：1，自引：1，他引：0  

Manuela Lasagna  Domenico Antonio De Luca  Laura Debernardi  Paolo Clemente 《Environmental Earth Sciences》2013,70(6):2767-2784

This paper discusses the effects of the dilution process on levels of aquifer contamination attenuation, developing analytical equations for application in theoretical and practical cases. The key finding is that, in aquifers, the dilution process causes a reduction of the contaminant concentration. Analytical equations for the assessment of the contaminant attenuation capacity, by means of the dilution process in an aquifer, are put forward. In particular, the attenuation of the contaminant concentration in an aquifer, and thus the dilution, is described by the volumetric flow rate per unit width perpendicular to the flow direction (q _u). Moreover, a classification of q _u was developed, considering six classes of attenuation capacity due to dilution. For the equations validation, nitrate contamination attenuation due to dilution was analysed in two sample areas in Piedmont (North-West Italy). The results confirmed the hypothesis, evidencing high nitrate concentrations in areas with low q _u values, connected to low dilution rate of the contaminant in the groundwater; vice versa, low nitrate concentrations were evidenced in areas with high q _u values, due to a high nitrate dilution rate.  相似文献   

Redox-controlled iron isotope fractionation during magmatic differentiation: an example from the Red Hill intrusion, S. Tasmania   总被引：1，自引：1，他引：0  

Paolo A. Sossi  John D. Foden  Galen P. Halverson 《Contributions to Mineralogy and Petrology》2012,164(5):757-772

This study presents accurate and precise iron isotopic data for 16 co-magmatic rocks and 6 pyroxene–magnetite pairs from the classic, tholeiitic Red Hill sill in southern Tasmania. The intrusion exhibits a vertical continuum of compositions created by in situ fractional crystallisation of a single injection of magma in a closed igneous system and, as such, constitutes a natural laboratory amenable to determining the causes of Fe isotope fractionation in magmatic rocks. Early fractionation of pyroxenes and plagioclase, under conditions closed to oxygen exchange, gives rise to an iron enrichment trend and an increase in $ f_{{{\text{O}}_{2} }} $ of the melt relative to the Fayalite–Magnetite–Quartz (FMQ) buffer. Enrichment in Fe³⁺/ΣFe_melt is mirrored by δ⁵⁷Fe, where ^VIFe²⁺-bearing pyroxenes partition ⁵⁷Fe-depleted iron, defining an equilibrium pyroxene-melt fractionation factor of $ \Updelta^{57} {\text{Fe}}_{{{\text{px}} - {\text{melt}}}} \le - 0.25\,\permille \times 10^{6} /T^{2} $ . Upon magnetite saturation, the $ f_{{{\text{O}}_{2} }} $ and δ⁵⁷Fe of the melt fall, commensurate with the sequestration of the oxidised, ⁵⁷Fe-enriched iron into magnetite, quantified as $ \Updelta^{57} {\text{Fe}}_{{{\text{mtn}} - {\text{melt}}}} = + 0.20\,\permille \times 10^{6} /T^{2} $ . Pyroxene–magnetite pairs reveal an equilibrium fractionation factor of $ \Updelta^{57} {\text{Fe}}_{{{\text{mtn}} - {\text{px}}}} \approx + 0.30\,\permille $ at 900–1,000?°C. Iron isotopes in differentiated magmas suggest that they may act as an indicator of their oxidation state and tectonic setting.  相似文献