2019_programme: SEISMO-ACOUSTIC WAVE PROPAGATION IN THE RADE OF HYÈRES (FRANCE) GENERATED BY COUNTER-MINING OF EXPLOSIVE DEVICES : COMPARISON BETWEEN NUMERICAL SIMULATIONS AND REAL EXPERIMENTS

• Session: 07. Underwater Unexploded Ordnance (UXO) Detection and Remediation
  Organiser(s): Jans Wolfgang, Richardson Mike
• Lecture: SEISMO-ACOUSTIC WAVE PROPAGATION IN THE RADE OF HYÈRES (FRANCE) GENERATED BY COUNTER-MINING OF EXPLOSIVE DEVICES : COMPARISON BETWEEN NUMERICAL SIMULATIONS AND REAL EXPERIMENTS
  Paper ID: 846
  Author(s): Favretto-Cristini Nathalie, Wang Fang, Garlan Thierry, Demoilin Xavier, Morio Olivier, Ambrois David, Beucler Eric, Cristini Paul
  Presenter: Cristini Paul
  Presentation type: oral
  Abstract: \n Explosive devices from World War II are discovered every week on the French coasts. In a short time after their discovery, they must be destroyed by the French Navy Mine Warfare Office. If the risks are well known by mine warfare experts, the consequences of counter-mining on the marine environment are much more complex to evaluate and expertise is then required. Depending on the environment geology, the explosive charges and their localization, the seismo-acoustic waves generated by the explosion may cause damage to infrastructures located on the coast, and under specific conditions, small submarine landslides. The POSA project, led by SHOM, and which includes LMA, Géoazur and LPG Nantes, focuses on the Mediterranean coast and proposes to address the upstream hazard management issue of such counter-mining operations in the marine field. The goal is to identify these risks for specific configurations and to develop a decision support tool for their control by comparing numerical simulations of seismo-acoustic wave propagation with acoustic data recorded within the coastal zone at sea and seismic data recorded on the coast, together with sedimentary measurements.\nWe propose here to present the results of such a methodology applied to the counter-mining campaign which occurred in the Rade of Hyères (France) in December 2018. We focus more specifically on the numerical simulations using a spectral-element method of seismo-acoustic wave propagation in this area. The impact of the explosive device (source) charge and its location (on the seabed or in the water column), together with the impact of the marine environment properties, on the simulated signals have been studied. Comparisons between numerical results and data recorded by several seismometers deployed on the coast of Hyères and surrounding islands will be shown.
• Corresponding author: Dr Cristini Paul
  Affiliation: CNRS-LMA
  Country: France
  e-mail: