## Data-parallel wave equation datuming with irregular acquisition
topography

#### Dimitri Bevc

Seismic data gathered on land is distorted by
irregular acquisition topography. Seismic imaging algorithms are
generally applied
to data which is redatumed to a planar surface. In regions of mild topography
where the near surface velocity is much slower than the subsurface velocity,
a static shift is adequate for this transformation.
However, when the
necessary shift increases in magnitude and when the near surface velocity is not
much slower than the subsurface velocity, the static approximation becomes
inadequate. Under these circumstances static shift distorts the wave field
and degrades velocity analysis and imaging.
In this case wave equation datuming is more appropriate than static shift.

Wave equation datuming is much more computation intensive than static
shift and is therefore seldom applied.
Furthermore, redatuming may involve multiple applications of the datuming
routine to estimate the near surface velocity structure.
I implement a data parallel wave equation datuming
algorithm which can be applied to land data as an alternative
to static shift in order to improve velocity analysis and imaging and to
estimate near surface velocity structure. The Kirchhoff algorithm is
efficiently implemented on a Connection Machine CM5 and makes wave equation
datuming practical.

#### 63rd Ann. Internat. Mtg., Soc., Expl. Geophys., Expanded Abstracts,
197-200, (1993).