	US 12,276,189 B2
	Anti-collision well trajectory design
Xin Chen, Beijing (CN); Qing Liu, Beijing (CN); Lu Jiang, Beijing (CN); XiaoWei Sheng, Beijing (CN); and Paul Bolchover, Beijing (CN)
Assigned to SCHLUMBERGER TECHNOLOGY CORPORATION, Sugar Land, TX (US)
Appl. No. 17/597,424
Filed by Schlumberger Technology Corporation, Sugar Land, TX (US)
PCT Filed Jul. 7, 2020, PCT No. PCT/US2020/040969 § 371(c)(1), (2) Date Jan. 5, 2022, PCT Pub. No. WO2021/007194, PCT Pub. Date Jan. 14, 2021.
Claims priority of provisional application 62/871,759, filed on Jul. 9, 2019.
Prior Publication US 2022/0268147 A1, Aug. 25, 2022
Int. Cl. E21B 47/02 (2006.01); E21B 7/04 (2006.01); E21B 43/30 (2006.01); E21B 47/022 (2012.01)

CPC E21B 47/02 (2013.01) [E21B 7/04 (2013.01); E21B 43/30 (2013.01); E21B 47/022 (2013.01)]

20 Claims

1. A computer-implemented method of determining trajectories for a plurality of wells while avoiding collision between wells, the method comprising:

determining, by one or more processors of the computer, a zone of uncertainty for individual wells of the plurality of wells, whereby a plurality of zones of uncertainty are determined, and wherein each of the plurality of zones of uncertainty comprises a range of potential deviated locations for a location of a borehole of the respective individual well with respect to an expected location of the borehole;

determining, by the one or more processors of the computer, based on the plurality of zones of uncertainty, a minimum separation factor for individual wells of the plurality of wells, whereby a plurality of minimum separation factors is determined, and wherein determining the minimum separation factor for a respective individual well comprises:

determining a plurality of separation factors for the respective individual well, wherein the plurality of separation factors includes a separation factor for each pair of the respective individual well and another well of the plurality of wells, and wherein determining the separation factor for each respective pair is based on a distance between a first center of the respective individual well and a second center of the other well, a first zone of uncertainty of the respective individual well, and a second zone of uncertainty of the other well; and

determining the minimum separation factor from the plurality of separation factors;

determining, by the one or more processors of the computer, a gradient of a separation factor for at least one pair of the respective individual well and other well based on the respective plurality of separation factors, first zone of uncertainty, and second zone of uncertainty;

updating, in a memory system of the computer, a nudge position for at least one well of the plurality of wells, based on the separation factor gradient and the plurality of separation factors;

providing, by the one or more processors of the computer, based on the updating, nudge positions for the individual wells of the plurality of wells; and

outputting, by the one or more processors of the computer, a set of recommended collision-free nudging vectors to a display of the computer.