psava@mines.edu

Wavefield seismic imaging

Paul Sava

Center for Wave PhenomenaColorado School of Mines

psava@mines.edu

Wide-azimuth imaging

Elastic wavefield imaging

Interferometric imaging

Stereographic imaging

Stream computing

psava@mines.edu

Wide-azimuth imagingsynopsis

I Wide-azimuth acquisition

I Narrow-azimuth processing

I We need to develop methods forI illumination compensationI multiples suppressionI model building (velocity, anisotropy)

psava@mines.edu

Wide-azimuth imagingCWP research

Migration by wavefield extrapolation

I Wide-azimuth wavefield extrapolation

I Extended (cross-correlation) imaging condition

I 3D angle decomposition

psava@mines.edu

Wide-azimuth imaging

Elastic wavefield imaging

Interferometric imaging

Stereographic imaging

Stream computing

psava@mines.edu

Elastic wavefield imagingsynopsis

I Multi-component (vector) acquisition

I Single-component (scalar) processing

I We need to develop methods forI anisotropic elastic imagingI amplitude reconstructionI model building (anisotropy)

psava@mines.edu

Elastic wavefield imagingCWP research

Multi-component reverse-time migration

I Vector wavefield extrapolation

I Wavefield decomposition in pure wave modes

I Conventional/extended imaging condition

psava@mines.edu

psava@mines.edu

Izz

Ixz

Izx

Ixx

psava@mines.edu

IPP

IPS

ISP

ISS

psava@mines.edu

Wide-azimuth imaging

Elastic wavefield imaging

Interferometric imaging

Stereographic imaging

Stream computing

psava@mines.edu

Interferometric imagingsynopsis

I Depth migration assumes exact velocity

I Velocity analysis produces approximate velocity

I We need to develop methods forI imaging heterogeneous and irregular saltI imaging complex stratigraphyI imaging basalt, carbonates, etc.

psava@mines.edu

Interferometric imagingCWP research

Interferometric imaging condition

I Wavefield extrapolation in background model

I Image-space interferometric imaging

I Local averaging for statistical stability

psava@mines.edu

Conventional imaging

psava@mines.edu

Interferometric imaging

psava@mines.edu

Interferometric imaging

psava@mines.edu

Interferometric imaging

psava@mines.edu

Interferometric imaging

psava@mines.edu

Interferometric imaging

psava@mines.edu

Wide-azimuth imaging

Elastic wavefield imaging

Interferometric imaging

Stereographic imaging

Stream computing

psava@mines.edu

Stereographic imagingsynopsis

I Data interpretation exploits wavefield structure

I Imaging condition ignores wavefield structure

I We need to develop methods toI eliminate cross-talk due to multiple sourcesI eliminate cross-talk due to multi-pathingI eliminate cross-talk due to multiple reflectionsI eliminate cross-talk due to multiple wave-modes

psava@mines.edu

Stereographic imagingCWP research

Stereographic imaging condition

I Wavefield decomposition prior to imagingI propagation timeI local slope

I Sparse wavefield representation

I Imaging condition in decomposition domain

psava@mines.edu

Multiple sources

psava@mines.edu

psava@mines.edu

Multiple paths

psava@mines.edu

psava@mines.edu

psava@mines.edu

Shot 1 Shot 2

psava@mines.edu

Conventional I.C. Stereographic I.C.

psava@mines.edu

Wide-azimuth imaging

Elastic wavefield imaging

Interferometric imaging

Stereographic imaging

Stream computing

psava@mines.edu

Stream computingsynopsis

I Process seismic data on distributed systems

I Moore’s Law is dead! Long live Amdahl’s Law!

I We need to develop methods toI use new computer architectureI use new computing models (streams)

psava@mines.edu

Stream computingCWP research

Stream processing of seismic data

I Multi-core processing

I Stream processing on GPUs

I Benchmark: finite-difference modeling