Fault slip and rupture velocity inversion by isochrone backprojection     

Gaetano Festa  Aldo Zollo 《Geophysical Journal International》2006,166(2):745-756

  相似文献   

A simple approach to the transformation of spherical harmonic models under coordinate system rotation     

A. De Santis  J. M. Torta  C. Falcone 《Geophysical Journal International》1996,126(1):263-270

  相似文献   

Interpretation of radon anomalies in seismotectonic and tectonic-gravitational settings: the south-eastern Crati graben (Northern Calabria, Italy)   总被引：1，自引：0，他引：1  

C. Tansi  A. Tallarico  G. Iovine  M. Folino Gallo  G. Falcone   《Tectonophysics》2005,396(3-4):181-193

The study area is located in the south-eastern part of the Crati valley (Northern Calabria, Italy), which is a graben bordered by N–S trending normal faults and crossed by NW–SE normal left-lateral faults. Numerous severe crustal earthquakes have affected the area in historical time. Present-day seismic activity is mainly related to the N–S faults located along the eastern border of the graben. In this area, much seismically induced deep-seated deformation has also been recognised.In the present paper, radon concentrations in soil gas have been measured and compared with (a) lithology, (b) Quaternary faults, (c) historical and instrumental seismicity, and (d) deep-seated deformation.The results highlight the following:

(a) There is no evidence of a strong correlation between lithology and the radon anomalies.

(b) A clear correlation between the N–S geometry of radon anomalies and the orientation of main fault systems has been recognised, except in the southernmost part of the area, where the radon concentrations are strongly affected by the superposition of the N–S and the NW–SE fault systems.

(c) Epicentral zones of instrumental and historical earthquakes correspond to the highest values of radon concentrations, probably indicating recent activated fault segments. In particular, high radon values occur in the zones struck by earthquakes in 1835, 1854, and 1870.

(d) Deep-seated gravitational deformation generally coincides with zones characterised by low radon concentrations.

In the studied area, the anisotropic distribution of radon concentrations is congruent with the presence of neotectonic features and deep-seated gravitational phenomena. The method used in this study could profitably contribute towards either seismic risk or deep-seated gravitational deformation analyses.  相似文献   

Progress in isotope paleohydrology using lake sediment cellulose     

Brent B. Wolfe  Matthew D. Falcone  Ken P. Clogg-Wright  Cherie L. Mongeon  Yi Yi  Bronwyn E. Brock  Natalie A. St. Amour  William A. Mark  Thomas W. D. Edwards 《Journal of Paleolimnology》2007,37(2):221-231

Recent advances in sample preparation techniques and mass spectrometry have fostered more routine oxygen isotope analysis of aquatic cellulose in lake sediment cores, a proxy for lake water oxygen isotope history. These methodological developments have significantly increased the feasibility of incorporating this approach into high-resolution, multi-site, and multi-proxy studies, which are frequently necessary to answer complex hydrological, hydroecological and hydroclimatic questions requiring a paleoenvironmental perspective. Direct translation of lake sediment aquatic cellulose oxygen isotope composition into lake water oxygen isotope composition offers appreciable opportunity for quantitative paleohydrological reconstructions, as evidenced by studies conducted over the past 15 years that span Holocene and pre-historical timescales.  相似文献   

Expected loss‐based alarm threshold set for earthquake early warning systems     

Iunio Iervolino  Massimiliano Giorgio  Gaetano Manfredi 《地震工程与结构动力学》2007,36(9):1151-1168

Earthquake early warning systems (EEWS) seem to have potential as tools for real‐time seismic risk management and mitigation. In fact, although the evacuation of buildings requires warning time not available in many urbanized areas threatened by seismic hazard, they may still be used for the real‐time protection of critical facilities using automatic systems in order to reduce the losses subsequent to a catastrophic event. This is possible due to the real‐time seismology, which consists of methods and procedures for the rapid estimation of earthquake features, as magnitude and location, based on measurements made on the first seconds of the P‐waves. An earthquake engineering application of earthquake early warning (EEW) may be intended as a system able to issue the alarm, if some recorded parameter exceeds a given threshold, to activate risk mitigation actions before the quake strikes at a site of interest. Feasibility analysis and design of such EEWS require the assessment of the expected loss reduction due to the security action and set of the alarm threshold. In this paper a procedure to carry out these tasks in the performance‐based earthquake engineering probabilistic framework is proposed. A merely illustrative example refers to a simple structure assumed to be a classroom. Structural damage and non‐structural collapses are considered; the security action is to shelter occupants below the desks. The cost due to a false alarm is assumed to be related to the interruption of didactic activities. Results show how the comparison of the expected losses, for the alarm‐issuance and non‐issuance cases, allows setting the alarm threshold on a quantitative and consistent basis, and how it may be a tool for the design of engineering applications of EEW. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

Evaluation of seismic energy demand     

Gaetano Manfredi 《地震工程与结构动力学》2001,30(4):485-499

In this paper, a method is proposed in order to obtain a simplified representation of hysteretic and input energy spectra. The method is based on the evaluation of the equivalent number of cycles correlated to the earthquake characteristics by the proposed seismic index I_D. This procedure allows us to obtain peak values of the hysteretic and input energy that depend on the demanded ductility, on the seismic index I_D and on the peak pseudo‐velocity. The assessment of the input energy represents a first step towards the definition of a damage potential index capable of taking into account the effect of the duration of the ground motions. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

Erratum to: Measurements of volcanic SO2 and CO2 fluxes by combined DOAS,Multi-GAS and FTIR observations: a case study from Turrialba and Telica volcanoes     

Vladimir Conde  Philippe Robidoux  Geoffroy Avard  Bo Galle  Alessandro Aiuppa  Angélica Muñoz  Gaetano Giudice 《International Journal of Earth Sciences》2014,103(8):2349-2349

  相似文献   

Spatial modelling and uncertainty assessment of pyroclastic cover thickness in the Sorrento Peninsula     

Federica Lucà  Gabriele Buttafuoco  Gaetano Robustelli  Antonio Malafronte 《Environmental Earth Sciences》2014,72(9):3353-3367

Assessing spatial variability of soil thickness is a critical issue for understanding and predicting slope processes. The present work was aimed at estimating the spatial scales at which the variation of pyroclastic cover thickness occurs in a sample area in the Sorrento Peninsula (Italy). Stochastic simulation was used to understand the spatial variability of pyroclastic cover thickness on Mount Pendolo and to assess its spatial uncertainty. In the study area, covering about 0.7 km², thickness measurements were collected using electrical resistivity tomography profiles, continuous core drillings and steel rod penetrometric tests. Variographic analysis revealed the occurrence of an anisotropic behaviour along the N50 and N140 directions. In the latter anisotropic direction, a nested variogram was fitted including (1) a long-range component which could be related to large-scale factors, like the curvature of the slope and contributing area and (2) a shorter scale variation which is probably associated with the occurrence of denudation processes or to the articulate cover/bedrock interface. To assess the spatial variability and uncertainty of pyroclastic cover thickness, a stochastic simulation algorithm was used and 500 equally probable images of cover thickness were yielded. The results showed that a better thickness distribution map can be drawn by simulating the data collected on the slope and at the footslope separately. The approach also allowed delineating the areas characterized by greater uncertainty, suggesting supplementary measurements to further improve the cover thickness distribution model, thus reducing the uncertainty.  相似文献   

Treatment of ground-motion predictive relationships for the reference seismic hazard map of Italy     

Valentina?MontaldoEmail author  Ezio?Faccioli  Gaetano?Zonno  Aybige?Akinci  Luca?Malagnini 《Journal of Seismology》2005,9(3):295-316

In the framework of the 2004 reference seismic hazard map of Italy the amplitude of the strong-motion (expressed in terms of Peak Horizontal Acceleration with 10% probability of non-exceedence in 50 years, referred to average hard ground conditions) was computed using different predictive relationships. Equations derived in Italy and in Europe from strong-motion data, as well as a set of weak and strong-motion based empirical predictive relationships were employed in a logic tree procedure, in order to capture the epistemic uncertainty affecting ground-motion attenuation. This article describes the adjustments and conversions required to eliminate the incompatibilities amongst the relations. Particularly significant are distance conversions and style-of-faulting adjustments, as well as the problems related to the use of regional relations, such as the selection of a reference depth, the quantification of random variability and the strong-motion prediction. Moreover, a regional attenuation relationship specific for volcanic areas was also employed, allowing a more realistic evaluation of seismic hazard, as confirmed by the attenuation of macroseismic intensities.  相似文献   

Modelling the transverse behaviour of circular tunnels in structured clayey soils during earthquakes     

Cabangon  Lowell Tan  Elia  Gaetano  Rouainia  Mohamed 《Acta Geotechnica》2019,14(1):163-178

Acta Geotechnica - The paper presents novel results from advanced numerical simulations of the transverse behaviour of shallow circular tunnels in natural clays accounting for soil structure...  相似文献