Estimating Thermal Response Test Coefficients: Choosing Coordinate Space of The Random Function     

Roberto Bruno  Francesco Tinti  Sara Focaccia 《Mathematical Geosciences》2016,48(1):3-23

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A three-dimensional particle finite element model for simulating soil flow with elastoplasticity     

Wang  Liang  Zhang  Xue  Lei  Qinghua  Panayides  Stelios  Tinti  Stefano 《Acta Geotechnica》2022,17(12):5639-5653

Acta Geotechnica - Soil flow is involved in many earth surface processes such as debris flows and landslides. It is a very challenging task to model this large deformational phenomenon because of...  相似文献   

Tsunami Excitation by Submarine Slides in Shallow-water Approximation     

S. Tinti  E. Bortolucci  C. Chiavettieri 《Pure and Applied Geophysics》2001,158(4):759-797

-- Landslide-induced tsunamis are receiving increased attention since there is evidence that recent large devastating events have been caused by underwater mass failures. Normally, numerical models are used to simulate tsunami excitation, most of which are based on shallow water, known also as long wave, approximation to the full equations of hydrodynamics. Analytical studies may handle only simplified problems, but help understand the basic features of physical processes. This paper is an analytical investigation of long-water waves excited by rigid bodies sliding on the sea bottom, based on the shallow-water approximation, which is here derived by properly scaling Euler equations for an inviscid, incompressible and irrotational ocean. In one-dimensional (1-D) cases (where motion depends only on one horizontal coordinate), under the further assumptions of small-height slide, which permits the recourse to linear theory, and of flat ocean floor, a solution for arbitrary body shape and velocity is deduced by applying the Duhamel theorem. It is also shown that this theorem can be advantageously used to obtain a general solution in case of a non-flat ocean floor, when the sea bottom follows a special power law, that can be adapted to study reasonable bottom profiles. The characteristics of the excited tsunamis are then evaluated by computing solutions in numerous examples, with special focus on wave pattern and wave evolution. The energy of the wave system is shown to depend on time: it grows expectedly in the initial phase of tsunami generation, when the moving body transfers energy to the water, but it may also diminish later, implying that a certain amount of energy may pass back from water waves to the slide.  相似文献   

Observations of physical effects from tsunamis of December 30, 2002 at Stromboli volcano, southern Italy   总被引：1，自引：0，他引：1  

Stefano Tinti  Alessandra Maramai  Alberto Armigliato  Laura Graziani  Anna Manucci  Gianluca Pagnoni  Filippo Zaniboni 《Bulletin of Volcanology》2006,68(5):450-461

On December 30, 2002, following an intense period of activity of Stromboli volcano (south Tyrrhenian Sea, Italy), complex mass failures occurred on the northwest slope of the mountain which also involved the underwater portion of the volcanic edifice for a total volume of about 2–3×10⁷ m³. Two main landslides occurred within a time separation of 7 min, and both set tsunami waves in motion that hit the coasts of Stromboli causing injuries to three people and severe damage to buildings and structures. The tsunamis also caused damage on the island of Panarea, some 20 km to the SSE from the source. They were observed all over the Aeolian archipelago, at the island of Ustica to the west, along the northern Sicily coasts to the south as well as along the Tyrrhenian coasts of Calabria to the east and in Campania to the north. This paper presents field observations that were made in the days and weeks immediately following the events. The results of the quantitative investigations undertaken in the most affected places, namely along the coasts of Stromboli and on the island of Panarea, are reported in order to highlight the dynamics of the attacking waves and their impact on the physical environment, on the coastal structures and on the coastal residential zone. In Stromboli, the tsunami waves were most violent along the northern and northeastern coastal belt between Punta Frontone and the village of Scari, with maximum runup heights of about 11 m measured on the beach of Spiaggia Longa. Measured runups were observed to decay rapidly with distance from the source, typical of tsunami waves generated by limited-area sources such as landslides.  相似文献   

Seismic sample areas defined from incomplete catalogues: an application to the Italian territory   总被引：1，自引：0，他引：1  

F. Mulargia  S. Tinti 《Physics of the Earth and Planetary Interiors》1985,40(4):273-300

The comprehensive understanding of earthquake source-physics under real conditions requires the study not of single faults as separate entities but rather of a seismically active region as a whole, accounting for the interaction among different structures. We define “seismic sample area” the most convenient region to be used as a natural laboratory for the study of seismic source physics. This coincides with the region where the average large magnitude seismicity is the highest. To this end, time and space future distributions of large earthquakes are to be estimated. Using catalog seismicity as an input, the rate of occurrence is not constant but appears generally biased by incompleteness in some parts of the catalog and possible nonstationarities in seismic activity. We present a statistical procedure which is capable, under a few mild assumptions, of both detecting nonstationarities in seismicity and finding the incomplete parts of a seismic catalog. The procedure is based on Kolmogorov-Smirnov nonparametric statistics, and can be applied without a priori assuming the parent distribution of the events. The efficiency of this procedure allows the analysis of small data sets. An application to the Italian territory is presented, using the most recent version of the ENEL seismic catalog. Seismic activity takes place in six well defined areas but only five of them have a number of events sufficient for analysis. Barring a few exceptions, seismicity is found stationary throughout the whole catalog span 1000–1980. The eastern Alps region stands out as the best “sample area”, with the highest average probability of event occurrence per time and area unit. Final objective of this characterization is to stimulate a program of intensified research.  相似文献   

Application of the extreme value approaches to the apparent magnitude distribution of the earthquakes     

Tinti  S.  Mulargia  F. 《Pure and Applied Geophysics》1985,123(2):199-220

The apparent magnitude of an earthquakey is defined as the observed magnitude value and differs from the true magnitudem because of the experimental noisen. Iff(m) is the density distribution of the magnitudem, and ifg(n) is the density distribution of the errorn, then the density distribution ofy is simply computed by convolvingf andg, i.e.h(y)=f*g.If the distinction betweeny andm is not realized, any statistical analysis based on the frequency-magnitude relation of the earthquake is bound to produce questionable results. In this paper we investigate the impact of the apparent magnitude idea on the statistical methods that study the earthquake distribution by taking into account only the largest (or extremal) earthquakes. We use two approaches: the Gumbel method based on Gumbel theory (Gumbel, 1958), and the Poisson method introduced byEpstein andLomnitz (1966). Both methods are concerned with the asymptotic properties of the magnitude distributions. Therefore, we study and compare the asymptotic behaviour of the distributionsh(y) andf(m) under suitable hypotheses on the nature of the experimental noise. We investigate in detail two dinstinct cases: first, the two-side limited symmetrical noise, i.e. the noise that is bound to assume values inside a limited region, and second, the normal noise, i.e. the noise that is distributed according to a normal symmetric distribution.We further show that disregarding the noise generally leads to biased results and that, in the framework of the apparent magnitude, the Poisson approach preserves its usefulness, while the Gumbel method gives rise to a curious paradox.  相似文献   

The Tsunami of August 17, 1999 in Izmit Bay,Turkey   总被引：2，自引：0，他引：2  

Altinok  Y.  Tinti  S.  Alpar  B.  Yalçiner  A. C.  Ersoy  Ş  Bortolucci  E.  Armigliato  A. 《Natural Hazards》2001,24(2):133-146

The Kocaeli 1999 Earthquake with an Mw = 7.4 caused major hazards throughout the NW of Turkey from Tekirdag to Bolu. Historical data indicates that some of the earthquakes around Izmit Bay have caused tsunamis. In this study, tsunami research for the Kocaeli 1999 Earthquake has been made also taking into consideration historical data. In this research more than about 70 data at 35 localities have been used to determine the tsunami evidences in the bay. Coastal observations indicated runups which were ranging from 1 to 2.5 m along the shores. However, the wave runups are more complex along the south coast due to the presence of coastal landslides (Deirmendere, Halidere, Ulasli, Karamürsel) and subsided areas (Kavakli to Yeniköy) along the shore. West of Yalova, evidence of tsunami rapidly diminished. In addition, possible tectonic mechanism has been determined by using 33 single-channel high-resolution digital seismic reflection profiles which were acquired following the Kocaeli 1999 Earthquake. As a result it has been determined that the Kocaeli Earthquake has created tsunami in Izmit Bay.  相似文献   

Energy of Water Waves Induced by Submarine Landslides   总被引：4，自引：0，他引：4  

S. Tinti  E. Bortolucci 《Pure and Applied Geophysics》2000,157(3):281-318

—Water waves generated by submarine landslides may constitute a serious hazard for coastal population and environment. These masses may be giant, as documented by several examples in recent history and by numerous geological traces of paleo-events. A theoretical investigation on wave generation and wave energy is performed here by using a model that is based on some simplifying assumptions. The landslide is treated as a rigid body moving underwater according to a prescribed velocity function. Water waves are governed by the shallow-water wave equations, where water velocity is constant through the water layer and vertical velocity is negligibly small. Geometrically simple basins are considered with either constant depth or constant slope, since attention is focused on the fundamental characteristics of the generation process. Analytical 1-D solutions as well as 1-D and 2-D numerical results obtained by means of a finite-element model are used to gain understanding of the energy transfer from a moving body to the water. From the 1-D examples, it is found that if slide duration is sufficiently long, water usually gains energy in the form of waves until a saturation point is reached, when body motion is no longer capable of producing a net transfer of energy from the rigid body to water. Finite-duration motions of a body moving at constant speed along a flat ocean floor can be used as canonical examples, since bottom slopes cannot significantly change the generated wave pattern. Typically, two trough-crest systems are developed that travel in opposite directions, with the leading crest in the direction of the slide and the leading trough toward the other direction. The amplitude of the former is generally higher, with amplitude controlled by the Froude number (ratio of body velocity to long waves phase celerity) and wavelength dictated by landslide length. Generation and propagation of 2-D cases show a more complicated pattern, since lateral radiation plays an important role. Some of the features present in the 1-D models are observed in 2-D wavefields, however substantial differences arise. The most significant difference is that no energy saturation takes place in 2-D, since the body transfers energy to the water as long as it moves.  相似文献   

Contributions expected from marine geodesy to the study of tsunamis in the Mediterranean Sea     

Stefano Tinti 《Marine Geodesy》2013,36(3-4):243-254

Abstract

In the Mediterranean Sea, tsunamigenic sources may be found in several areas in the belt running from Gibraltar up to the Black Sea, but they are concentrated mainly around Italy and Greece. Most of the sources are located close to the coasts and excite tsunamis reaching the coasts soon after the generation time. Tsunami research and tsunami mitigation programs are only in a very initial stage in the Mediterranean area. The present activities are focused chiefly to tsunami potential evaluation and on tsunami propagation modeling. The establishment of efficient observational networks, centers for data management and services, and systems for issuing tsunami warnings are some of the most urgent needs. In this context, the envisaged contribution of marine geodesy is twofold. First, monitoring of submarine active faults and submarine volcanic areas by means of systems capable of detecting seafloor deformation may contribute in identifying periods in which the probability of tsunami generation increases beyond a threshold value, especially in those tsunamigenic zones where geodetic observations on land are insufficient (for example, eastern Sicily in Italy and the Hellenic Arc in southern Greece). Second, since most of the active sources are close to the coastline, computations of tsunami propagation and run‐up may be significantly enhanced by a better knowledge of the bathymetry of the seabelt facing the coasts.  相似文献   

Introduction to ��Tsunamis in the World Ocean: Past, Present, and Future. Volume I��     

Kenji Satake  Alexander Rabinovich  Utku Kano?lu  Stefano Tinti 《Pure and Applied Geophysics》2011,168(6-7):963-968

Eighteen papers are included in Volume 1 of a PAGEOPH topical issue Tsunamis in the World Ocean: Past, Present, and Future. These papers are briefly introduced. They are grouped into three categories: case studies of earthquake-generated tsunamis; tsunami forecast and hazard assessments; and theoretical and computational modeling of tsunami generation, propagation, and coastal behavior. Most of the papers were presented at the 24th International Tsunami Symposium held 14?C16 July 2009 in Novosibirsk, Russia, and reflect the current state of tsunami science.  相似文献