As Many As Four Dolomite Benches in the Three Forks May Have Oil Potential -- The Bakken, North Dakota, USA

Link here. And reported earlier here.

As many as four dolomite benches in the Three Forks formation that underlies the Bakken in the Williston basin may have oil potential, said Continental Resources Inc., Enid, Okla.

Continental in 2011 cut six cores of the entire vertical thickness of the Three Forks formation, which is 180-270 ft thick under its acreage, over a distance of 115 miles north to south. The cores revealed that the formation has up to four separate benches of dolomite that contain oil.

Continental initially targeted the first bench of Three Forks, about 20 ft below the Lower Bakken shale, in mid-2008 (OGJ Online, July 10, 2008).

In October Continental’s Charlotte 2-22H well in McKenzie County, ND, made 1,140 b/d of oil equivalent on its first 24-hr test as the company’s first horizontal test of a deeper Three Forks bench. The well’s lateral taps the second bench 50 ft below a typical first-bench lateral.

These are not very thick benches, or layers. Amazing how skilled these folks are to push a drill bit in such a narrow band almost two miles down and two miles of horizontal: if six cores in formation 270 feet thick, the average bench is 45 feet.  That's incorrect; there are only four benches, and there is separation between them; see first comment below.