Seismic Modeling
The primary objective of seismic modeling, popularily known as forward modeling, is to generate synthetic seismic data for a given earth model. It is an inherent part of seismic imaging algorithms such as RTM (Reverse Time Migration) and FWI (Full Waveform Inversion). Major inputs of seismic modeling are a model of the subsurface geological structures & associated physical parameters, wavelet and source & receiver layouts. Outcome of this algorithm are a recorded seismogram due to recording of wavefield at near surface locations and snapshots of wavefield at different timesteps during propagation. The complexity of this alogorithm depends upon the choice of the medium, wave equation and mathematical method in order to solve the equations e.g., homogenous to heterogenous, isotropic to anisotropic medium, acoustic to elastic to visco elastic wave equation, finite difference to finite element to finite volume method. Also, the computing requirements of this algorithm increases with the complexity of the solution and the choice of mathematical method.
We have developed seismic acoustic modeling application (Acomod) for 2D heterogenous medium using finite-difference methods. The parallel implementation of this application uses domain decomposition at node level using MPI and OpenMP within the node, thus exhibiting hybrid MPI + OpenMP programming technique. The optimized application has been successfully ported on Intel’s Xeon Phi.
Acomod: Complex synthetic velocity model.
Acomod: Snapshots of wavefront generated by Acomod.
Currently, we are involved in enhancing this work to increase the order of finite-difference from 4th to 8th & 16th order in space and also implementing it for 3D medium. Further, optimization and porting of this higher order finite-difference based application on multi and many core architecture will be carried out. Also working on the development of an efficient 2D elastic modeling application suitable for hybrid computing platform. These applications will be used with advanced imaging applications such as FWI and RTM.
Contact Person
Ms Richa Rastogi
(Associate Director)
Email: richar[at]cdac[dot]in, contactsdp[at]cdac[dot]in