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Concept

Tomographie sismique

Publications associées (22)

The use of ductile steel fuses for the seismic protection of acceleration sensitive non- structural components: Numerical and Experimental verification

Dimitrios Lignos, Ahmed Mohamed Ahmed Elkady

Recent seismic events have showcased the vulnerability of non-structural components to even low- or moderate-intensity earthquakes that occur far more frequently than design-basis ones. Thus, community-critical buildings, such as hospitals, telecommunicati ...

EEME2023

A Probabilistic Physics-Based Seismic Hazard Model for the Alborz Region, Iran

Alireza Khodaverdian

The seismic activity rate is one of the most significant factors in seismic hazard modeling. Although it is usually estimated from observed seismicity, a complete picture of the possible earthquakes is not always available since catalogs of the observed ea ...

SEISMOLOGICAL SOC AMER2022

Origin of the Co‐Seismic Variations of Elastic Properties in the Crust: Insight From the Laboratory

Marie Estelle Solange Violay, François Xavier Thibault Passelègue, Mateo Alejandro Acosta, Federica Paglialunga

Seismological observations highlighted that earthquakes are often followed by changes in elastic properties around the fault zone. Here, we studied the origin of these variations using stick-slip experiments on saw-cut granite samples presenting different ...

2021

Experimental plastic reactivation of pseudotachylyte‐filled shear zones

Marie Estelle Solange Violay, François Xavier Thibault Passelègue

Pseudotachylytes are fine‐grained fault rocks that solidify from melt that is produced in fault zones during earthquakes. Exposed sections of natural fault zones reveal evidence of post‐seismic plastic deformation (i.e. reactivation) of pseudotachylyte, wh ...

2021

Consistent Tomography over Diffusion Networks under the Low-Observability Regime

Ali H. Sayed, Augusto José Rabelo Almeida Santos

This work considers a diffusion network responding to streaming data, and studies the problem of identifying the topology of a subnetwork of observable agents by tracking their output measurements. Topology inference from indirect and/or incomplete dataset ...

IEEE2018

Robust and adaptive approaches for Relative Geologic Time Estimation

Mireille El Gheche

For a geoscientist, the Relative Geologic Time (RGT) is an important tool to perform chronostratigraphic analysis. However, automatically estimate an RGT image from a seismic image can be a challenging task where we have to respect seismic features, the de ...

ELSEVIER SCIENCE BV2018

Composition of the low seismic velocity E ′ layer at the top of Earth's core

James Badro

Using ab initio simulations on Fe-Ni-S-C-O-Si liquids, we constrain the origin and composition of the low-velocity layer E′ at the top of Earth's outer core. We find that increasing the concentration of any light element always increases velocity and so a ...

2017

From closed testaments to books: Virtual X-ray Reading as an alternate digitization technology for fragile documents

Giorgio Margaritondo, Demetri Psaltis, Fauzia Albertin

In recent years, research and technology made considerable progress in increasing the speed and the safety of the entire digitization process of ancient collections. Despite this, imaging ancient, fragile or un-opened documents remains a formidable challen ...

Soc Imaging Science & Technology2017

The importance of mantle wedge heterogeneity to subduction zone magmatism and the origin of EM1

Stéphane Laurent Escrig

The composition of the convecting asthenospheric mantle that feeds the mantle wedge can be investigated via rear-arc lavas that have minimal slab influence. This "ambient mantle wedge" composition (the composition of the wedge prior to the addition of a sl ...

Elsevier2017

Seismic Simultaneous Source Separation via Patchwise Sparse Representation

Pascal Frossard

The concept of simultaneous source has recently become of interest in seismic exploration, due to its efficient or economic acquisition or both. The blended data overlapped between shot records are acquired in simultaneous source acquisition. Separating th ...

Ieee-Inst Electrical Electronics Engineers Inc2016

Primordial metallic melt in the deep mantle

Susannah McGregor Dorfman

Seismic tomography models reveal two large low shear velocity provinces (LLSVPs) that identify large-scale variations in temperature and composition in the deep mantle. Other characteristics include elevated density, elevated bulk sound speed, and sharp bo ...

Amer Geophysical Union2016

Chemical Characterisation of Deep Earth Reservoirs

Hélène Marie Piet

Seismic imaging of the internal Earth has emphasized the inhomogeneity of its mantle. This interface layer of nearly 3000 km surrounding the central metallic core conducts heat released from the latter, which played a significant role in shaping the actual ...

EPFL2016

Plasticity of the dense hydrous magnesium silicate phase A at subduction zones conditions

Yi Wang, Elodie Adeline Amiguet

The plasticity of the dense hydrous magnesium silicate (DHMS) phase A, a key hydrous mineral within cold subduction zones, was investigated by two complementary approaches: high-pressure deformation experiments and computational methods. The deformation ex ...

Elsevier2015

3D galaxy clustering with future wide-field surveys: Advantages of a spherical Fourier-Bessel analysis

Anaïs Marie Rassat

Context. Upcoming spectroscopic galaxy surveys are extremely promising to help in addressing the major challenges of cosmology, in particular in understanding the nature of the dark universe. The strength of these surveys, naturally described in spherical ...

EDP Sciences2015

Le facteur séisme dans l'architecture vernaculaire : un décryptage entre déterminants culturels, types de structures et ressources cognitives parasismiques

Milo Hofmann

A large part of ancient built environments in earthquake prone areas have been accomplished exclusively thanks to the experience that their builders developed over centuries of practice. Several of the resulting techniques have showed a satisfactory perfor ...

EPFL2015

A seismologically consistent compositional model of Earth's core

James Badro

Earth's core is less dense than iron, and therefore it must contain "light elements," such as S, Si, O, or C. We use ab initio molecular dynamics to calculate the density and bulk sound velocity in liquid metal alloys at the pressure and temperature condit ...

National Academy of Sciences2014

Multiscale Interior Tomography Using 1D Generalized Total Variation

Michaël Unser, John Paul Ward

We propose a method for accurate and fast reconstruction of the interior of a 2D or 3D tomographic image from its incomplete local Radon transform. Unlike the existing interior tomography work with 2D total variation, the proposed algorithm guarantees exac ...

The University of Utah2014

Seismic shear distribution among interconnected cantilever walls of different lengths

Katrin Beyer, Raluca-Tereza Constantin, Sabrina Simonini

Mid- to high-rise buildings in seismic areas are often braced by slender reinforced concrete (RC) walls, which are interconnected by RC floor diaphragms. In design it is typically assumed that the lateral forces are distributed in proportion to the wall’s ...

2014

Coupled seismogenic geohazards in Alpine regions

Lyesse Laloui, Pierino Lestuzzi, Alessio Ferrari, Fabrice Dupray, Amin Karbassi, Cyrill Silvan Baumann

COupled seismogenic GEohazards in Alpine Regions (COGEAR) is an interdisciplinary natural hazard project investigating the hazard chain induced by earthquakes. It addresses tectonic processes and the related variability of seismicity in space and time, ear ...

2012

Graph-Based Information Processing : Scaling Laws and Applications

Amin Karbasi

We live in a world characterized by massive information transfer and real-time communication. The demand for efficient yet low-complexity algorithms is widespread across different fields, including machine learning, signal processing and communications. Mo ...

EPFL2012