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SUMMARY:Space and time discretization of the wave equation for the reverse
  time migration
DTSTART:20091202T161500
DTSTAMP:20260405T212412Z
UID:b448a4b045ce466850674ba46ed15d1bd8fdee581d480e24cc23ada5
CATEGORIES:Conferences - Seminars
DESCRIPTION:Dr. Julien Diaz\nSince the work of Hemon [1] in the 70s\, it i
 s well-known from the geophysical community that the seismic imaging metho
 ds based on the solution of the full wave equation are the most efficient 
 and accurate to deal with very complex propagation media\, when compared t
 o the ones based on the solution of the one-way wave equation. Nowadays on
 e of the most commonly used imaging technique is the Reverse Time Migratio
 n (RTM)\, which relies on many successive solutions of the wave equation.\
 nAs all the migration techniques\, RTM follows the Claerbouts schedule : n
 umerical propagation of the source function (propagation) and of the recor
 ded wavefields (retropropagation) and next\, construction of the image by 
 applying an imaging condition. The retropropagation step can be realized a
 ccouting for the time reversibility of the wave equation. To be efficient\
 , especially in three dimensional domain\, the RTM requires the solution o
 f the full wave equation by fast numerical methods. Finite element methods
  are considered as the best discretization method for solving the wave equ
 ation\, even if they lead to the solution of huge systems with several mil
 lions of degrees of freedom\, since they use meshes adapted to the domain 
 topography and the boundary conditions are naturally taken into account in
  the variational\nformulation. Among the different finite element families
 \, the spectral element one (SEM) [2\, 3\, 4] is very interesting because 
 it is compatible with the use of a Gauss Lobatto quadrature rule which lea
 ds\nto a diagonal mass matrix and does not hamper the order of convergence
  of the finite element method. 
LOCATION:MAA110
STATUS:CONFIRMED
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