Time reversal location of glacial earthquakes

In 2003, Ekström et al. reported the detection and location of a new class of earthquakes occurring in the polar regions of the Earth. The proposed source mechanism involves large and sudden sliding motions of glaciers, which gave the name “glacial earthquakes” to these events. In this study we localize some of these earthquakes with a time reversal mirror (TRM) algorithm, which, contrary to ordinary back projection methods, does not involve testing each possible source location. In TRM localization, an earthquake is located on the basis of only one 3-D spectral element simulation of seismic wave propagation by using the full complexity of recorded data as simultaneous time-reversed sources. We show that on the basis of this approach, even glacial earthquakes with a faint signal can be correctly localized and that the pattern of the time-reversed wavefield is coherent with the motion of glaciers down their valley

Time-reversal imaging of seismic sources and application to the great Sumatra earthquake

International audienceThe increasing power of computers and numerical methods (like spectral element methods) allows continuously improving modelization of the propagation of seismic waves in heterogeneous media and the development of new applications in particular time reversal in the three-dimensional Earth. The concept of time-reversal (hereafter referred to as TR) was previously successfully applied for acoustic waves in many fields like medical imaging, underwater acoustics and non destructive testing. We present here the first application at the global scale of TR with associated reverse movies of seismic waves propagation by sending back long period time-reversed seismograms. We show that seismic wave energy is refocused at the right location and the right time of the earthquake. When TR is applied to the Sumatra-Andaman earthquake (26 Dec. 2004), the migration of the rupture from the south towards the north is retrieved. Therefore, TR is potentially interesting for constraining the spatio-temporal history of complex earthquakes

Ian Short et Brian Merrilees, éd. — Benedeit : The Anglo-Norman Voyage of Saint Brendan, 1979

Larmat Jean. Ian Short et Brian Merrilees, éd. — Benedeit : The Anglo-Norman Voyage of Saint Brendan, 1979. In: Cahiers de civilisation médiévale, 25e année (n°98), Avril-juin 1982. pp. 160-162

Renata Anna Bartoli. — La « Navigatio sancti Brendani » e la sua fortuna nella cultura romanza dell'età di mezzo. Fasano di Brindisi, Schena, 1993.

Larmat Jean. Renata Anna Bartoli. — La « Navigatio sancti Brendani » e la sua fortuna nella cultura romanza dell'età di mezzo. Fasano di Brindisi, Schena, 1993.. In: Cahiers de civilisation médiévale, 38e année, supplément annuel 1995. Comptes Rendus. pp. 3-4

L'enfant dans L'Escoufle de Jean Renart

Les protagonistes de L'Escoufle pendant une notable partie du roman, sont deux enfants, le fils du comte de Montivilliers et la fille de l'empereur de Rome. Le roman nous fait connaître les rapports qu'ils ont avec leurs parents, leur entourage et chante leurs amours. L'attention exceptionnelle dont ils sont l'objet mérite qu'on ne néglige pas ce roman quand on essaie de savoir ce que pouvait être l'enfant des familles aristocratiques à la fin du xiie siècle. +++ Le récit s'intéresse d'abord ..

Ian Short et Brian Merrilees, éd. — Benedeit : The Anglo-Norman Voyage of Saint Brendan, 1979

Larmat Jean. Ian Short et Brian Merrilees, éd. — Benedeit : The Anglo-Norman Voyage of Saint Brendan, 1979. In: Cahiers de civilisation médiévale, 25e année (n°98), Avril-juin 1982. pp. 160-162

Guy Demerson, Rabelais, une vie, une œuvre, une époque

Larmat Jean. Guy Demerson, Rabelais, une vie, une œuvre, une époque. In: Bulletin de l'Association d'étude sur l'humanisme, la réforme et la renaissance, n°23, 1986. pp. 85-88

Renata Anna Bartoli et Fabrizio Cigni, éd. — Benedeit, il « Viaggio di son Brandano ». Parme, Nuova Pratiche Ed., 1994 (" Bibl. mediev. ", 32)

Larmat Jean. Renata Anna Bartoli et Fabrizio Cigni, éd. — Benedeit, il « Viaggio di son Brandano ». Parme, Nuova Pratiche Ed., 1994 (" Bibl. mediev. ", 32). In: Cahiers de civilisation médiévale, 38e année, supplément annuel 1995. Comptes Rendus. p. 4

Renata Anna Bartoli. — La « Navigatio sancti Brendani » e la sua fortuna nella cultura romanza dell'età di mezzo. Fasano di Brindisi, Schena, 1993.

Larmat Jean. Renata Anna Bartoli. — La « Navigatio sancti Brendani » e la sua fortuna nella cultura romanza dell'età di mezzo. Fasano di Brindisi, Schena, 1993.. In: Cahiers de civilisation médiévale, 38e année, supplément annuel 1995. Comptes Rendus. pp. 3-4

Renata Anna Bartoli et Fabrizio Cigni, éd. — Benedeit, il « Viaggio di son Brandano ». Parme, Nuova Pratiche Ed., 1994 (" Bibl. mediev. ", 32)

Larmat Jean. Renata Anna Bartoli et Fabrizio Cigni, éd. — Benedeit, il « Viaggio di son Brandano ». Parme, Nuova Pratiche Ed., 1994 (" Bibl. mediev. ", 32). In: Cahiers de civilisation médiévale, 38e année, supplément annuel 1995. Comptes Rendus. p. 4