AMBROIS , David

ABSTRACT This study presents the analysis of the seismic records of eight underwater explosions triggered by the French Navy Mine Warfare Office in December 2018 in the Bay of Hyères, southeast France. The explosions (charges of 80–680 kg TNT-equivalent) were recorded by 17 temporary stations composed of medium-to-broadband velocimeters and...

Nous suivons la vie d'un puits Résif, depuis sa création, jusqu'à son sablage. Un comparatif des signaux est fait sur les puits Résif de l'OCA-Géoazur.

The French Navy Mine Warfare Office conducted a series of 8 calibrated underwater explosions in December 2018 in the Bay of Hyères, SE France. The charges were ranging from 80 to 680 kg TNT-equivalent weights and the generated mechanical waves have been recorded at 17 seismic stations (composed of velocimeters, accelerometers and/or...

Over the past two years, several important actions have marked the operation of Résif stations by OCA-Géoazur. Among these activities, this poster presents the azimuth alignment of all Résif sensors, the installation of sensors in the Durance River stations using a new system of watertight tanks, the ISO, SAOF and PIAF stations and the...

This poster presents the steps from the creation of Résif wells to their sanding, as well as a comparison of the signals from the OCA-Geoazur's Résif wells in the seismological stations BLAF (Entrevennes, 04), MLYF (Forcalquier, 04), TRIGF (Trigance, 83) and ARTF (Artigues, 83). This poster was presented during the Résif Scientific and...

Le poster articulé en 2 parties présentent l'impact de la tempête Alex sur la récupération des données, et aussi des signaux mesurés par diverses stations Résif (dont RAP) installées à proximité des vallées concernées.

International audience

On November 26, 2019, SEIS, the first broadband seismometer designed for the Martian environment (Lognonné et al., 2019) landed on Mars thanks to NASA's InSight mission. On April 6, 2019 (sol 128), the InSight Science team detected the first historical "marsquake" (NASA news release). Before it was recorded, the InSight Science team developed...

International audience

In many seismically active areas of the world, earthquake-induced landslides commonly account for a significant portion of the total impact of earthquakes. When landslides occur offshore, in coastal areas, they can generate proximal tsunami waves that reach the coastlines in only a few minutes, and can be very dangerous.The triggering power of...

International audience

Haiti lies in an area that regularly experiences destructive earthquakes, but monitoring has been limited due to economical and political situation. Recent projects using citizen-hosted seismometers, and a temporary deployment in response to the 2021 M7.4 earthquake have provided a wealth of seismic data. Still, the high noise levels recorded...

L'action spécifique Sismologie Marine Mobile (SMM) a été créée au sein de Résif. Les 3 parcs OBS français se sont fédérés pour offrir une instrumentation marine de pointe pouvant répondre aux besoins des chercheurs. Le projet d'investissement d'avenir Marmor, financé par l'ANR (PIA3-ESR-Equipex+), permet l'achat et la jouvence d'instruments de...

International audience

On August 2021, a Mw 7.2 earthquake struck Haiti's southern peninsula, eleven years after the devastating Mw 7 January 12, 2010 earthquake that occurred near Port au Prince. This large event, called the Nippes earthquake, has been recorded locally by the citizen network composed of low-cost raspberry shake stations. A precise analysis of the...

On 2 October 2020, the Maritime Alps in southern France were struck by the devastating Storm Alex, which caused locally more than 600 mm of rain in less than 24 h. The extreme rainfall and flooding destroyed regional rain and stream gauges. That hinders our understanding of the spatial and temporal dynamics of rainfall–runoff processes during...

Explosive devices from World War II are discovered almost every week on the French coasts and they must be destroyed by the French Navy Mine Warfare Office. The consequences of the counter-mining on the marine environment are complex to evaluate. Depending on the environment geology, the explosive charges and their localization, the...

Unexploded historical ordnance (UXO) from World War II, that is discovered almost every week close to the French coast, must be destroyed quickly after discovery to ensure the safety of divers and ships. The favored destruction method is countermining, i.e., the use of a high-order detonation conducted by exploding an additional donor charge...

Abstract Seismic monitoring in Haiti is currently provided by a mixed network of low-cost Raspberry Shake (RS) seismic stations hosted by citizens, and short-period and broadband stations located mainly in neighboring countries. The level of earthquake detection is constantly improving for a better spatio-temporal distribution of seismicity as...

The goal of the work presented in a two-companion paper is to pave the way for reliably assessing the risks of damage to buildings on the shore, induced by the detonation of unexploded historical ordnance (UXO) of large weights in variable shallow water environments with a water depth less than 50 m. The risk assessment is quantified through...

Unexploded historical ordnance (UXO) from World War II, that is discovered almost every week close to the French coast, must be destroyed quickly after discovery to ensure the safety of divers and ships. The favored destruction method is countermining, i.e., the use of a high-order detonation conducted by exploding an additional donor charge...

The 14 August 2021 Mw 7.2 Haiti earthquake struck a decade after the devastating 2010 event within the Enriquillo Plantain Garden Fault Zone in the Southern peninsula of Haiti. Space geodetic results show that the rupture is composed of both left-lateral strike-slip and thrust motion, similar to the 2010 rupture, but aftershock locations from a...

ABSTRACT The 14 August 2021 Mw 7.2 Haiti earthquake struck 11 yr after the devastating 2010 event within the Enriquillo Plantain Garden (EPG) fault zone in the Southern peninsula of Haiti. Space geodetic results show that the rupture is composed of both left-lateral strike-slip and thrust motion, similar to the 2010 rupture; but aftershock...

Le projet POSA a pour but de décrire et quantifier l'énergie sismique se propageant sur les côtes lors des explosions de contre-minage menées par la Marine. En 2018, un déploiement de capteurs proches des côtes a permis d'enregistrer les champs d'ondes sur une large gamme de fréquences. Le signal lié aux explosions se caractérise par deux...

RESIF 2019, Rencontres scientifiques et techniques, Biarritz, FRANCE, 12-/11/2019 - 14/11/2019