Gulf of Mexico deepwater
discoveries down, but not out
It has been a tough year for deepwater drill- ing in the US Gulf of Mexico. The number of drilling rigs in the Gulf is down by three, from 22 to 19, compared to last year, ac- cording to the Baker Hughes rig count
of Dec. 15, 2017. And that number is down by
39 compared to three years ago, when the US
active offshore rig count stood at 58.
Still, there have been a number of important
deepwater discoveries made and announced
over the past year.
In December 2016, Anadarko announced
that its Warrior exploration well encountered
more than 210 ft of net oil pay in multiple high-quality Miocene-aged reservoirs. The Warrior
discover y is approximately 3 mi ( 5 km) from the
Anadarko-operated K2 field and is expected to
be tied back to its Marco Polo production facility.
The company and partner Ecopetrol drilled a
successful appraisal well, Warrior- 2, in 2Q 2017.
Anadarko also announced that it had encoun-
tered more than 90 ft of high-quality oil pay in a
Pliocene-aged reservoir at its Phobos appraisal
well, located approximately 12 mi ( 19 km) south
of the Lucius spar. A tieback from Phobos to
Lucius is being studied.
In May 2017, Anadarko reported that it had
drilled the first development well at Horn Moun-
tain, encountering more than 70 ft of net oil pay.
It also reported that the Calpurnia exploration
well in Green Canyon block 25 encountered
nearly 60 ft of oil pay in Miocene-aged sands.
Calpurnia is expected to be tied back to one
of Anadarko’s nearby operated facilities in the
Green Canyon protraction area.
In August, BHP Billiton reported that it had
made an oil discovery in multiple horizons at its
Wildling- 2 appraisal well in the Green Canyon
area. The Wildling field is located in Green
Canyon block 530 in 4,035 ft of water. The Wildling- 2 well was spudded by Transocean’s ultra-deepwater drillship Deepwater Invictus in April.
In September, LLOG Exploration Co. LLC
announced that Seadrill’s ultra-deepwater drillship West Neptune would drill and complete
two wells as part of its Buckskin project in the
deepwater Gulf of Mexico. The West Neptune
was scheduled to move to the Buckskin location in 4Q 2017.
The Buckskin field is located in Keathley
Canyon blocks 785, 828, 829, 830, 871, and 872,
in 6,800 ft of water. The Keathley Canyon 872
No. 1 discovery well at Buckskin was drilled
by Repsol in 2009 to a depth of 29,404 ft and
encountered 400 ft of net pay in the Upper and
Lower Wilcox formations. Three subsequent
appraisal wells drilled in Keathley Canyon blocks
785 and 829 encountered an average of 375 ft
of high-quality oil pay in the Upper Wilcox.
The company estimates Buckskin has 5 Bbbl
of oil in place.
LLOG has been active in several deepwater areas of the Gulf, and issued a general update on its
drilling programs in September. The company
notes that from January 2016 to August 2017,
it had made 12 discoveries in the deepwater
Gulf. A quick rundown of some of this activity
is listed below.
• The Claiborne discovery in Mississippi Canyon block 794 is located in 1,500 ft of water
and was drilled to a total depth of 24,000 ft
and targeted multiple subsalt, oil-bearing Miocene sands. The discovery well was drilled
by LLOG as operator in 2015 and was successfully appraised with a second well in late
2016. Both wells have been completed and
are being tied-back to the Walter-operated
Coelacanth platform on Ewing Bank 834.
• The LaFemme discover y in Mississippi Canyon block 427 is located in 5,800 ft of water
and was drilled to a total depth of 13,000 ft and
targeted multiple Upper Miocene reservoirs.
The discovery well was drilled by LLOG as
operator in mid-2016 and encountered more
than 175 ft of net oil pay and was success-
fully appraised by a follow up well in later
that year. Both wells have been completed
and will be co-developed with the Blue Wing
Olive discovery and tied back to the LLOG-operated Delta House facility on Mississippi
Canyon block 254.
• The Blue Wing Olive discovery is located
in Mississippi Canyon blocks 427-471, also
in 5,800 ft of water, and was drilled to a total
depth of 17,000 ft and targeted multiple Upper
Miocene zones. The discovery well was drilled
by LLOG as operator in mid-2016 and will be
completed in two oil and natural gas reser-
voirs. The company is currently completing
the Blue Wing Olive well. First production is
expected in mid-2018 from both the LaFemme
and Blue Wing Olive developments.
• The Red Zinger discovery in Mississippi Can-
yon block 257 is located in 6,000 ft of water
and was drilled to a total depth of 19,000 ft
and found multiple Upper Middle Miocene
targets. The discovery well was drilled by
LLOG as operator in 2016. Red Zinger will be
tied-back to the LLOG-operated Delta House
facility. First production is expected in the
second half of 2018.
• Marmalard East in Mississippi Canyon block
301 is a field-extension well in 5,300 ft of water
that was drilled and completed by LLOG as
operator in 2Q 2017. The well was drilled to a
total depth of 18,000 ft and targeted Miocene
sands and encountered more than 50 ft of net
oil pay. The well was brought onto production
through the Marmalard subsea infrastructure
system to the Delta House facility at a rate in
excess of 12,000 b/d of oil.
• Crown & Anchor, a previously-announced
two-well discovery in 4,200 ft of water in Vi-
osca Knoll blocks 959, 960, 1003 and 1004,
was drilled by LLOG as operator in 2015
to a total depth of 14,000 ft targeting multiple Upper Miocene sands. Both wells have
been completed and will be tied back to the
Anadarko-operated Marlin facility in Viosca
Knoll blocks 871 and 915. First production is
expected in 2Q 2018.
For more on these and other drilling efforts
in the Gulf of Mexico, please see the 2018 Status
of US Gulf of Mexico deepwater discoveries
survey starting on page 27. •
Left: Transocean’s ultra-deepwater drillship Deepwater Invictus spudded BHP Billiton’s Wildling- 2 in
April. (Courtesy Transocean) Right: Seadrill’s ultra-deepwater drillship West Neptune is scheduled to
drill two wells as part of LLOG’s Buckskin project. (Courtesy Seadrill Ltd.)