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Figure 8. Definition of Data listing codes, zipcodes, and related cities.
Interpretation of seismic data
requires loop tying. Imagine a box, with seismic data similar
to Figure 2 on each of the four vertical
sides of the box. If a subsurface "topography" map is being made
of an interface between layers of rock, represented by a seismic
wavelet, then the same reflector needs to be connected at each
corner of the box. The geologic complication is rock layers have
been folded and faulted (structural changes) and eroded or not
deposited in areas (stratigraphic changes). Seismic surveys
consist of grids and volumes of these “loops.” The key to
seismic interpretation is to tie all of the loops and make sure
the reflectors are connected at each corner of each box. There
are no short cuts, and the data forces honesty. Automatic
reflection pickers speed up the process by orders of magnitude,
and they still work by tieing every loop. In my experience,
those without personal integrity are not comfortable doing
mundane jobs like tying seismic loops. To be a good interpreter,
it takes a willingness to continually question the interpretation,
and a willingness to redo a lot of work when a mistie is
recognized, particularly since there are always project time and
budget pressures. To get the most out of seismic data, there must
be integrity in each stage of handling the data.
At the turn of the millennium I decided to stop building tools for exploration geophysicists, and to use commercially available tools to participate in finding hydrocarbon reserves. It did not take long to realize the business side of oil exploration does not have the same integrity as the geophysical technical side. Does that mean that all of the people working the business side of petroleum exploration are crooks?
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paradoxes