Analysis of the series of precipitation at Padova,Italy     

Dario Camuffo 《Climatic change》1984,6(1):57-77

The series of rainfall at Padova, Italy, for the years 1725–1981, is among the longest in the world. This paper concerns itself with both the history and analysis of the data: in fact operational procedures, rain gauges, sites and data quality have been carefully investigated since the beginning of the series and are herewith described. Afterwards, seasonal variations, trends, periodicities, vacillations and recurrence intervals of the frequency, precipitation amount and intensity of the monthly totals are discussed. From this analysis, the seasonal variation and a secular trend are well evident; the periodicities are generally modest and not well defined; the vacillations appear to be recurrent through-out the entire series. In conclusion, the analysis of this long series may be a useful tool not only for helping in the practical utilization of the rainfall, but also for gaining an insight into the possible mechanisms of climatic fluctuations.  相似文献   

Post-seismic relaxation and earthquake triggering in the southern Adriatic region   总被引：1，自引：0，他引：1  

Marcello Viti  Francesca D'Onza  Enzo Mantovani  Dario Albarello  Nicola Cenni 《Geophysical Journal International》2003,153(3):645-657

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Guidelines for the good practice of surface wave analysis: a product of the InterPACIFIC project     

Sebastiano Foti  Fabrice Hollender  Flora Garofalo  Dario Albarello  Michael Asten  Pierre-Yves Bard  Cesare Comina  Cécile Cornou  Brady Cox  Giuseppe Di Giulio  Thomas Forbriger  Koichi Hayashi  Enrico Lunedei  Antony Martin  Diego Mercerat  Matthias Ohrnberger  Valerio Poggi  Florence Renalier  Deborah Sicilia  Valentina Socco 《Bulletin of Earthquake Engineering》2018,16(6):2367-2420

Surface wave methods gained in the past decades a primary role in many seismic projects. Specifically, they are often used to retrieve a 1D shear wave velocity model or to estimate the V_S,30 at a site. The complexity of the interpretation process and the variety of possible approaches to surface wave analysis make it very hard to set a fixed standard to assure quality and reliability of the results. The present guidelines provide practical information on the acquisition and analysis of surface wave data by giving some basic principles and specific suggestions related to the most common situations. They are primarily targeted to non-expert users approaching surface wave testing, but can be useful to specialists in the field as a general reference. The guidelines are based on the experience gained within the InterPACIFIC project and on the expertise of the participants in acquisition and analysis of surface wave data.  相似文献   

Optimal design and seismic performance of tuned mass damper inerter (TMDI) for structures with nonlinear base isolation systems          下载免费PDF全文

Dario De Domenico  Giuseppe Ricciardi 《地震工程与结构动力学》2018,47(12):2539-2560

The tuned mass damper inerter (TMDI) couples the classical tuned mass damper (TMD) with an inerter, a mechanical device whose generated force is proportional to the relative acceleration between its terminals, thus providing beneficial mass‐amplification effects. This paper deals with a dynamic layout in which the TMDI is installed below the isolation floor of base‐isolated structures in order to enhance the earthquake resilience and reduce the displacement demand. Unlike most of the literature studies that assumed a linearized behavior of the isolators, the aim of this paper is to investigate the effectiveness of the TMDI while accounting for the nonlinearity of the isolators. Two nonlinear constitutive behaviors are considered, a Coulomb friction model and a Bouc‐Wen hysteretic model, representative of friction pendulum and of lead‐rubber‐bearing isolators, respectively. Optimal design is based on the stochastic dynamic analysis of the system, by modeling the base acceleration as a Kanai‐Tajimi filtered stationary random process and resorting to the stochastic linearization technique to handle the nonlinear terms. Different tuning criteria based on displacement, acceleration, and energy‐based performance indices are defined, and their implications in a design process are discussed. It is proven that the improved robustness of the TMDI reduces its performance sensitivity to the tuning frequency and to the earthquake frequency content, which are well‐known shortcomings of TMD‐like systems. This important feature makes the TMDI particularly suitable for nonlinear base‐isolated structures that are affected by unavoidable uncertainties in the isolators' properties and that may experience changes of isolators effective stiffness depending on the excitation level.  相似文献   

Rock physics modelling and inversion for saturation-pressure changes in time-lapse seismic studies     

Xiaozheng Lang  Dario Grana 《Geophysical Prospecting》2019,67(7):1912-1928

Time-lapse seismic data are generally used to monitor the changes in dynamic reservoir properties such as fluid saturation and pore or effective pressure. Changes in saturation and pressure due to hydrocarbon production usually cause changes in the seismic velocities and as a consequence changes in seismic amplitudes and travel times. This work proposes a new rock physics model to describe the relation between saturation-pressure changes and seismic changes and a probabilistic workflow to quantify the changes in saturation and pressure from time-lapse seismic changes. In the first part of this work, we propose a new quadratic approximation of the rock physics model. The novelty of the proposed formulation is that the coefficients of the model parameters (i.e. the saturation-pressure changes) are functions of the porosity, initial saturation and initial pressure. The improvements in the results of the forward model are shown through some illustrative examples. In the second part of the work, we present a Bayesian inversion approach for saturation-pressure 4D inversion in which we adopt the new formulation of the rock physics approximation. The inversion results are validated using synthetic pseudo-logs and a 3D reservoir model for CO₂ sequestration.  相似文献   

Characterisation and modelling of marine dissolved organic matter interactions with major and trace cations     

Yoann Louis  Cédric Garnier  Véronique Lenoble  Dario Omanović  Stéphane Mounier  Ivanka Pižeta 《Marine environmental research》2009,67(2):100-107

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Combining genetic and linearized algorithms for a two-step joint inversion of Rayleigh wave dispersion and H/V spectral ratio curves     

Matteo Picozzi  Dario Albarello 《Geophysical Journal International》2007,169(1):189-200

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Thermal springs,fumaroles and gas vents of continental Yemen: Their relation with active tectonics,regional hydrology and the country’s geothermal potential     

Angelo Minissale  Mohamed A. Mattash  Orlando Vaselli  Franco Tassi  Ismail N. Al-Ganad  Enrico Selmo  Nasr M. Shawki  Dario Tedesco  Robert Poreda  Abdassalam M. Ad-Dukhain  Mohammad K. Hazzae 《Applied Geochemistry》2007

Most thermal springs of continental Yemen (about 65 emergences at 48 sampling sites) and a couple of fumaroles and boiling water pools have been sampled and analyzed for chemical and isotopic composition in the liquid phase and the associated free-gas phase. Whatever the emergence, all the water discharges have an isotopic signature of meteoric origin. Springs seeping out from high altitudes in the central volcanic plateau show a prevalent Na–HCO₃-composition, clearly affected by an anomalous flux of deep CO₂ deriving from active hydrothermal systems located in the Jurassic Amran Group limestone sequence and/or the Cretaceous Tawilah Group, likely underlying the 2000–3000 m thick volcanic suite. At lower elevations, CO₂ also affects the composition of some springs emerging at the borders of the central volcanic plateau.  相似文献   

Benthic foraminifera from the upper Collio Formation (Lower Permian, Lombardy Southern Alps): implications for the palaeogeography of the peri-Tethyan area     

Dario Sciunnach 《地学学报》2001,13(2):150-155

New palaeontological evidence points to a temporary marine transgression in the Early Permian into the Collio Basin, a major palaeogeographic feature of the present-day Southern Alps. The thick volcaniclastic succession filling the basin (Collio Formation) is widely held as deposited in alluvial to lacustrine settings. Rare calcareous foraminifers were recently found in a single sandstone interval, containing phosphate nodules, from the uppermost Collio Formation. A temporary seaway, necessary for the foraminifera to spread into a continental basin, implies that (i) the Collio Basin lake was not only an intramontane (as commonly viewed), but also a coastal lake, and (ii) its altitude did not exceed the amplitude of a first-order sea-level rise, that is, about 100 m. These constraints, along with striking similarities as to tectonic context, accumulation rates and geochemical signature, suggest that the Collio Basin was a California-type basin, resembling in particular the present-day Salton Sea (CA, USA).  相似文献   

A resampling approach to test stress-field uniformity from fault data     

Dario Albarello 《Geophysical Journal International》2000,140(3):535-542

Several methods have been proposed to constrain the stress field from fault plane orientations and slip directions within a crustal volume characterized by brittle deformation. All the methods are based on the assumption that the stress field is uniform in the volume considered. If this hypothesis is not checked in advance, however, the methodology may lead to misleading conclusions. In this work, a procedure is defined to check stress-field uniformity by a statistical analysis of the available fault data. Since, in most cases, the statistical features of the uncertainties that affect such data are not well known, a distribution-free approach is proposed. It is based on a simple search algorithm, devoted to selecting stress configurations compatible with available data, combined with a bootstrap resampling approach. The test results are more conservative than the ones so far proposed in the literature. When the test allows stress heterogeneities to be safely excluded, approximate confidence intervals for the principal stress directions can be obtained; otherwise, the level of stress heterogeneity present in the volume under study can be assessed. An application of the proposed procedure to a sample of fault data deduced from seismological data is presented.  相似文献