Start Date: April 19, 2017 - 04:15 PM
End Date: April 19, 2017 - 05:15 PM
Abstract: Time-lapse seismic reservoir surveillance is a proven
technology for offshore environments. In the past two decades,
we have seen this technology move from novel to necessary
and enable us to monitor injection wells, water influx,
compaction, undrained fault blocks, and bypassed reserves.
Value is generated by influencing the management of our field
operations and optimizing wells to reduce cost, accelerate
production, and increase ultimate recovery.
Significant advances in technology are improving the quality of
our data. Errors in acquisition repeats are nearly eliminated
using permanently installed systems or dedicated ocean- bottom
nodes. We now routinely obtain surveys with such a high
signal-to-noise ratio that we can observe production-induced
changes in the reservoir after months instead of years. This
creates a demand for frequent seismic monitoring to better
understand the dynamic behavior of our fields. Increasing the
frequency of seismic monitoring will have a proportionate cost
implication, and a challenge is how to design a monitoring program that maximizes the overall benefit to
Reducing individual survey costs is important to enable frequent monitoring. Several techniques are
considered for lowering these costs such as:
There is no single solution that works for every field, and we need to understand the pros/cons of the
various technologies to select the best option for a specific field. Some results of applying these
techniques to offshore fields will be discussed.
- Reducing the number of shots and/or receivers to minimize offshore vessel time. This includes
shooting targeted (i4D-style) surveys on a frequent basis in between full-field surveys that are
- Use of smaller source arrays towed by less-expensive vessels.
- Semi-permanent ocean-bottom nodes that can be left on the seafloor for multiple on-demand
Time-lapse VSPs that use permanent distributed acoustic sensors (DAS) in well bores.
- High-resolution 4D surveys that monitor shallow reservoirs cost effectively using low-cost
vessels towing arrays of short-streamer cables (e.g., P-cable).
Bio: Paul Hatchell joined Shell in 1989 after receiving his PhD in theoretical physics from the University of
Wisconsin. He began his career at Shell’s Technology Center in Houston and worked on a variety of
research topics including shear-wave logging, quantitative seismic amplitude analysis, and 3D AVO
applications. Following a four-year oil and gas exploration assignment in Shell’s New Orleans office,
Paul returned to Shell’s technology centers in Rijswijk and Houston where he is currently a member of
the Areal Field Monitoring team and Shell’s principal technical expert for 4D reservoir surveillance. His
current activities include developing improved 4D seismic acquisition and interpretation techniques,
seafloor deformation monitoring, and training the next generation of geoscientists.