Velocity
Interpretation: Southern North Sea Gas Basin
Mel D. Carter, J. S. Fisher, S. W. Thomas
A data set including both seismic and well data from the Southern North Sea
gas basin illustrates several techniques for integrated velocity
interpretation
and depth conversion. The most important technique is the depth-normalized
interval
velocity
method. This approach is founded on an analysis of the
compaction characteristics of the geologic section and makes possible more
accurate
velocity
estimates from both well and seismic data.
The data set itself reveals several interesting phenomena. Unusually large
velocity
increases with depth of burial are present and these data are typically
available. Significant horizontal vs. vertical p-wave anisotropy is present in
the Tertiary layer.
Velocity
within the Zechstein Formation varies
systematically because of
variable
anhydrite content. Examples illustrate the
exploration significance of these phenomena.
AAPG Search and Discovery Article #91035©1988 AAPG-SEPM-SEG Pacific Sections and SPWLA Annual Convention, Santa Barbara, California, 17-19 April 1988.