is not your father's world of seismic.
words, seismic is no longer only for explorationists hunting for
new discoveries, traps and hydrocarbons. Today the technology can
help a project from conception all the way through the life of the
reservoir quality seismic is expanding the data's scope to every
phase of a project to reduce risk and uncertainty.
is reservoir quality seismic?
a good question with no definitive answer -- but here's a start:
Reservoir quality seismic can encompass newer techniques such as
4-D or time lapse seismic and multi-component seismic, but the term
also applies to advances that have dramatically improved the quality
and resolution of more traditional 3-D seismic.
of these technological advances is to define and derive changes
in reservoir properties such as saturation, porosity, permeability
and pressure based on seismic data, according to Stephen Pickering,
marketing manager for reservoir services with WesternGeco.
of seismic data over measurements that can be taken in the wellbore
is that seismic sees throughout the whole reservoir," Pickering
said. "Technologies such as multi-component seismic, which measures
both the pressure and shear waves ... allow us to define some rock
properties from seismic and relate those directly to the well information."
3-D seismic advances also are driving reservoir quality seismic
said more closely spaced streamers and a higher number of sensors
per streamer are yielding better sampling and improved imaging.
Contractors also are towing streamers at shallower depths, which
allows for better resolution.
today we have more advanced techniques to remove noise from the
data," he said, "and navigation technology allows us to place the
boats in the same place time after time, making the data more repeatable."
problem with 4-D seismic in the past was the repeatability of the
we were not able to precisely match a survey to a previous acquisition,
so there were differences in the rock geology and noise, in addition
to hydrocarbon production, which made it difficult to pinpoint just
the fluid movements," he said. "We had the concept of 4-D but we
were using old 3-D tools.
we are developing tools specially designed for 4-D reservoir-quality
seismic," he said, and they "address all the issues of better sampling,
higher resolution, less noise and streamer steering for repeatability."
operations, such as drilling and logging measurements, also can
benefit from seismic data, according to Pickering.
technology today can predict such things as geohazards, shallow
water flows and over pressure," he said. "Also, seismic can now
be used to geosteer the bit to land the well in the optimum part
of the reservoir. After a well is drilled seismic can now be used
to optimize production over time, which is the domain of 4-D seismic.
through to the end of production oil companies are interested in
only one thing -- getting the most oil out of the ground safely
using the fewest wells possible at the lowest cost," he said. "When
an operator has a high level of confidence in the seismic data and
can drill fewer appraisal wells to accurately quantify reserves,
that significantly impacts costs and the time to first production."
development reservoir quality seismic can aid in well placement
and design; during the production phase it can help maximize recovery.
field life if an operator can turn off certain wells to stop the
influx of water based on time lapse seismic they may be able to
extend the life of the field and improve hydrocarbon recovery,"
oil companies are leading the effort in reservoir-quality seismic,
and, as a result, calibrated and quantified seismic measurements
will be the "industry direction of the future."