UNCONVENTIONAL DRILLING
Defining control points
To address the unusual hump depicted
in the first well, for example, the team
set control points of known stratigraphic
depth and known measured depth to force
the algorithm to find a path through that
point. Flattening the cusps in the inter-
pretation of the second well required four
control points. The ability for a geologist to
intervene like this to address anomalies in
the automated interpretation is analogous
to checking and fixing the work of an
assistant, rather than having to do all the
work yourself.
“Instead of having to maintain an inter-
pretation constantly, you can just verify
what is going on and intervene one or two
times to produce this same type of inter-
pretation,” Mr Willerth said.
The team considered the number of con-
trol points to be a marker for the amount of
manual effort needed to reach an accept-
able automated interpretation. They esti-
mated it would take a geo-professional five
to 10 minutes to update a typical control
point. Compared with the large number
of monitoring updates required in tradi-
tional geosteering, relating to potentially
hundreds of surveys, the low number of
interventions required in the test wells
represents the removal of “a huge amount
of human effort,” Mr Willerth said.
“This suggests that we could poten-
tially dramatically expand the capability
of human geologists to monitor more and
more wells without compromising service
quality,” he said.
Refining the technology
The team plans to expand testing of the
algorithm to basins with more complicat-
ed geology to ensure that the results can
be replicated over a wider range of geo-
logical conditions. Since the completion
of the initial field trials, the company has
modified how the algorithm analyzes the
heat map, in order to reduce the amount of
manual intervention required for realistic
results. After running the Haynesville test
well data through the updated algorithm,
the need for control point intervention
dropped to none for the first well and just
two control points for the second.
H&P also expanded the algorithm’s
capacity to accept different forms of
human intervention, in addition to con-
Click here to watch a video interview with H&P’s Marc
Willerth from the 2022 IADC/SPE International Drilling
Conference on a separate paper he presented, “Fifty
Ways to Leave Your Wellbore: An Honest Look at the Causes
and Costs of Unplanned Sidetracks.”
trol points. The new functionality would
enable a geologist to tell the algorithm to
insert a fault of a certain size at a certain
location, for example, to reflect their seis-
mic knowledge of the area. The purpose
of the algorithm is to enable the human to
do the most important things – and not do
the unimportant things, Mr Willerth said.
“Selecting where a fault is, selecting
the size of the fault – this is an important
thing for a geologist to be analyzing and
putting in there. Saying the formation has
continued along the same dip for another
500 feet, saying there has not been a major
change, is something that you might as
well have a computer look at, and let the
human plan for the next well.”
H&P is also considering developing
other features for the algorithm, such as
the ability to actively alert the geosteering
supervisor to changes in certain metrics.
“That really expands how much a per-
son can watch, because now you know
when to look at it as opposed to just check-
ing every so often,” Mr Willerth said. “It’s
nice to only have to have a human inter-
vene five times. It’s even nicer if you can
tell them when they likely would need to
intervene.” DC
For more information, please see IADC/SPE
208697, “Field Validation of an Automated
Geosteering Algorithm
in the
Haynesville Shale.”
“It’s not that we want to replace someone
or remove their job. It’s that we want to make
sure that person can be more effective,
watch more wells and leverage their talents
in a better way.”
- Marc Willerth, Helmerich & Payne
D R I L L I N G C O N T R AC T O R • M AY/J U N E 202 2
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