For a few years now, unconventional oil and gas operators in the USA managed to squeeze 2 mile laterals in 1 mile acreages, by drilling lateral section of shale wells across lease areas, turning them and drilling a return section inside the same lease. Shell was the pioneer, with the first horseshoe well (NEELIE 1-85 LOV-4H) drilled in Loving County, Texas in 2019. It was followed by a few companies replicating the intriguing design over the next years.
U-turn, U-Laterals, horseshoe wells or paperclip wells were drilled in Wolfcamp and Bone Springs targets in the Permian Basin (in both Delaware and Midland sub-basins), also in the Eagle Ford shale, Niobrara and Utica shale. About 50 paperclip wells were executed in the US between 2020 and 2024.
More details about US paperclips can be found here:
A paperclip well design consists of a vertical hole, followed by a curve (or build section) that lands the well in the desired reservoir, then an ongoing leg, a 180 degrees turn that points the well in the opposite azimuth direction, and a return leg that brings the well close to the original landing point, thus doubling up on lateral length, even when constricted by mineral lease area. Wells can be stacked in multiple benches, or crossing over between benches.
Many Bakken wells in North Dakota have high turns in the lateral section, bending around land parcel boundaries to maximize drainage. The design earned the nickname “boomerang well” for its curved shape.
Canadian bent wells
High turn wells, where azimuth changes more than 180 degrees in the horizontal part of the well, have been drilled in Canada as well.
Obsidian (still named Penn West at the time) drilled a string of multilateral collector wells, with legs reaching between other Bluesky multilateral wells. The complicated well designs contained between 25 and 47 legs.
One of these wells, 100043008318W500, drilled in 2015, has legs on both sides of the build section that bend more than 180 degrees. Five of the 35 legs exhibit trajectories that start heading West and end up East bound.
Boomerang wells
Single leg boomerang wells, with horizontal sections turning up to 90 degrees in the middle of the lateral, were drilled by Kelt in Valhalla, targeting the Montney silt/shale. The first lateral of this kind dates back to 2015, when 102120807811W600 was drilled with a turn of 78 degrees midway through the lateral section.
Several other wells were drilled nearby, with turns of up to 90 degrees, , sometimes in stacked benches of the Montney Formation.
Drill-bit multilateral exploration
Ghost River kicked off several legs in different directions in their 100140503503W400 well, drilled in 2021. The well ended up with leg 6 turning 155 degrees in the lateral. Flexible well designs, and the ability to change directional plans on the fly makes this approach feasible when chasing thin sand beds with variable thickness.
The high lateral turn was not executed to extend the well, but rather to search for better sand in the laterally variable reservoir.
Cenovus drilled a few multilateral well targeting the Cummings member of the Mannville Group in their Rivercourse property in Eastern Alberta.
One of these wells, 100130104701W400, drilled in 2024, has legs draining the Cummings sand, extending for as long as good quality sand was observed in the well. Leg 5 bends a full 174 degrees in the lateral.
More boomerang wells are planned in unconventional reservoirs in Canada, with operators maximizing access to their resource when land access is tight. We are anxiously awaiting the first full bend U-Turn to be drilled in Canada. It should not be too long before we see the first paperclip well in the basin.