DATA SHEET
WellDefined Lateral Survey Optimization
Managing azimuthal uncertainty for collision avoidance
and well placement in the North Sea
For comparison, WellDefined Lateral* survey optimization uses real-time geomagnetic referencing
(GRS) to reduce the lateral error ellipse (before in blue) by up to 70% (after in red).
Get real-time GRS for accurate well placement
The North Sea, crowded with mature oil fields, has significant well
placement challenges. The obstacles faced by operators include small
geological targets and tightly packed predrilled reservoirs, resulting
in a small margin for well placement errors. Operators in the region
have used real-time WellDefined Lateral survey optimization to enable
accurate well placement with GRS—without the need for additional
survey tools.
Correct for magnetic interference to improve survey accuracy
WellDefined Lateral survey optimization dramatically reduces errors
associated with the Earth’s magnetic field by applying advanced
magnetic mapping techniques. A multistation analysis technique
is used to correct for drillstring interference. And, to complement
the GRS techniques used in the field, the effects of space weather
can be accounted for using data from magnetic observatories.
Using WellDefined Lateral corrections in the North Sea, operators
are able to drill in mature fields while avoiding collisions with nearby
wells, accessing geological targets in close proximity to each other.
This service’s error corrections and improved accuracy also prevent
operators from compromising production with inaccurate placement.
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Other company, product, and service names
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Copyright © 2013 Schlumberger. All rights reserved. 13-DR-0014
North Sea operators have applied WellDefined Lateral corrections to
ensure precise well placement and collision avoidance.
Reduce lateral error ellipse by up to 70% in the North Sea
Over multiple wellbores, the application of WellDefined Lateral survey
optimization has resulted in improved reservoir modeling with increased
certainty in LWD data. This service has reduced costs and rig time
associated with deep gyro surveys, eliminated the correction runs
sometimes associated with postrun surveys, and provided a superior
level of survey QA/QC.
This service reduces the ellipsoid of uncertainty by up to 70%,
increasing the accuracy of data used for well placement. On a
10-well campaign, the WellDefined Lateral service reduced rig time
by approximately 60 hours and reduced surveying costs by performing
survey corrections in real time.
In the North Sea, and similar mature fields, WellDefined Lateral survey
optimization has significantly improved operations with accurate
surveying data that enabled optimal well placement. These results
contributed to reduced rig time and associated costs, as well as better
understanding of the downhole environment and location of nearby wells.
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