Increasing Exploration Successes
Utilizing New Single-Sensor Seismic
Towed Streamer Acquisition Technology
By
Mohammed Badri1, Morten Svendsen1
(1) WesternGeco, N/A, Egypt
Significant improvements have been made over the last two decades in 3D
seismic
imaging that lead to large oil and gas discoveries in various geologic
basins. These improvements have, however, more or less completely focused on
increased efficiency of hydrocarbon exploration.
As oil and gas fields become mature in terms of their production life, better
understanding of the reservoirs is required to maximize hydrocarbon recovery and
optimize the net present value of these fields. This paper presents seismic
data
from well known fields in the Gulf of Mexico and North Sea, where revolutionary
new
seismic
technology has been applied to significantly improve the
seismic
resolution, amplitude accuracy and imaging quality of the reservoirs.
Seismic
has not only revealed the subsurface in exploration but also has
become a useful tool for reservoir management to map detailed, complex reservoir
features like thin-bed and fault resolution, fluid saturation and lithology
discrimination. This will require true amplitudes preservation, spatial as well
as the temporal sampling of the data, and development of new data processing and
analysis algorithms with sufficient confidence to influence decision making in
exploration and reservoir management.
Several case studies will be presented and are based on careful analysis of
earlier seismic
from the fields, which enabled us to set appropriate quality
requirements and specifications for the
seismic
imaging.
The data acquisition was performed using a new revolutionary seismic
system.
This system has the capacity to receive and record
seismic
data from each
individual hydrophone, to actively steer the
seismic
streamers laterally to keep
the cross-line spatial sampling close and constant even under the influence of
cross-currents, and to measure and compensate for variations in the
seismic
source signal from shot to shot.
The new single sensor towed streamer technology provides high quality seismic
data required for efficient and optimal drilling and production of a reservoir.