GEOL463
Seismic Reflection Imaging
*Acoustic (pressure) source is set off near the surface… *Sound waves propagate in all directions from the source… *0.1-10% of the energy reflects from subsurface contrasts… *This energy is recorded by surface or borehole “geophones”… *Times and amplitudes of these reflections are used to interpret the subsurface… *“Migration” (computer processing operation) is used to finally represent (“image”) the 2D or 3D structure at depth.
*
*
This is the “ideal” of seismic imaging – flat surface and collocated sources and receivers
In practice, multi-fold, offset recording is used, and zero-offset section is obtained by extensive data processing