Denbury Adds Dual-Lateral Wellbore on Anticline

Fallon County, Montana

Texas-based Denbury Onshore (Denbury) has received approval from Montana regulators to expand their multi-lateral Madison drilling program on the prolific Cedar Creek Anticline. The firm recently permitted the Cabin Creek #CH21-17NEH, ne-nw 17-10n-58e, Fallon County, and plans to drill a pair of horizontal pathways off the main wellbore. The lateral Charles segments will have bottom holes landing in the ne-se 8-10n-58e. Estimated true vertical depth for this prospect will be approximately 7,400’, with true measured depths for each lateral of roughly 11,582’. A vertical distance of 10’ will separate the wellbores. The Charles member of the Madison is expected to be encountered near 7,200’.

Denbury’s newest activity spots some 18 miles northeast of Baker, Mont., and within Cabin Creek Field, a huge oil pool that following its discovery in 1953 has cumulated more than 121 mmbo. This resource primarily produces from vertical and horizontal sections in the Silurian/Ordovician at depths approaching 9,000’.

The Cabin Creek #CH21-17NEH drillsite sits within a recently approved, 940-acre temporary spacing unit that encompasses portions of sections 8, 9, and 17 of 10n-58e. Overlapping previous divisions established for exploration of the horizontal Mission Canyon in this area, Denbury’s latest entity allows for drilling of a dual-lateral test targeting the Charles.

The drill pad for the Cabin Creek #CH21-17NEH already supports a horizontal Charles producer completed by Denbury in January 2018. Representing the operator’s northernmost horizontal Mississippian producer to-date on the Cedar Creek Anticline, the Unit #CH31-17SH, nw-ne 17-10n-58e, was given an IPF of 473 bopd, 5 mcfgpd, and 196 bwpd from the Charles section of the Madison at a vertical depth near 7,400’. This prospect was drilled to a true measured depth of 12,570’. Bottom hole terminated in the nw-nw 21-10n-58e.

Tops picked in the Unit #CH31-17SH include the Minnelusa at 6,148’, Kibbey at 6,886’, Madison at 7,056’, and the Charles at 7,197’. From December 2018 through May of 2019, this venture, which provided the first horizontal Charles production on the Cedar Creek Anticline, has yielded more than 33.8 k bo and 11 k bw.

In June of 2019, Denbury applied for and received permission from the state to re-enter and drill a second horizontal wellbore 13’ feet beneath the original producing pathway of the Unit #CH31-17SH. Bottom-hole location for the revision will be in the same spot as the original lateral. No activity has been reported for this proposed re-entry.

It is unclear how Denbury’s latest multi-lateral stakings could impact their unconventional Charles/Mission Canyon play along the Cedar Creek Anticline in both Wibaux and Fallon counties. It appears the Texas operator believes the Upper Madison Group could hold untapped potential, primarily in the Lower Charles.

Two miles south of the Cabin Creek #CH21-17NEH is the Cabin Creek Unit MC #44-20NH, se-se 20-10n-58e, which Denbury completed for an impressive 1,243 bopd, 50 mcfgpd, and 381 bwpd from the horizontal Mission Canyon at 7,780’–12,107’. Bottom hole for this well rests in the ne-nw 20-10n-58e. From October 2018 through July of 2019, the Cabin Creek Unit MC #44-20NH cumulated more than 152.0 k bo, 6.4 mmcfg, and 674 k bw. The Mission Canyon oil pay in this prospect was picked at a true vertical depth of 7,780’.

As mentioned, Denbury’s latest multi-lateral permit is located on the Cedar Creek Anticline, a geological feature situated mostly in Montana’s Dawson, Fallon, and Wibaux counties. The southeastern end of this fold terminates in portions of Bowman County, North Dakota; and Harding County, South Dakota. Denbury, who is a primary operator along the anticline, has an active program looking for horizontal Madison reserves in the region.

Encompassing several oil fields, the Cedar Creek Anticline produces mostly from the vertical and horizontal Silurian and Ordovician, and is estimated to contain up to 5 billion barrels of original-oil-in-place.