US 12,312,941 B2
Typelog alignment for automated geosteering
Jin Sun, Denver, CO (US); and Stefan Maus, Denver, CO (US)
Assigned to Magnetic Variation Services LLC, Denver, CO (US)
Filed by Magnetic Variation Services LLC, Denver, CO (US)
Filed on Nov. 14, 2023, as Appl. No. 18/509,073.
Application 18/509,073 is a continuation of application No. 17/821,758, filed on Aug. 23, 2022, granted, now 11,867,050.
Application 17/821,758 is a continuation of application No. 17/081,739, filed on Oct. 27, 2020, granted, now 11,466,560, issued on Oct. 11, 2022.
Prior Publication US 2024/0093594 A1, Mar. 21, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. E21B 7/06 (2006.01); E21B 47/0228 (2012.01)
CPC E21B 47/0228 (2020.05) [E21B 7/06 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for drilling, the method comprising:
accessing, by a computer system, typelog reference data respectively associated with a plurality of reference wells;
using the typelog reference data, performing, by the computer system, a typelog alignment for the typelog reference data using multi-stage optimization to generate an aligned depth log, wherein performing the typelog alignment for the typelog reference data associated with the plurality of reference wells using multi-stage optimization further comprises:
preprocessing, by the computer system, the typelog reference data, including a rank transformation and multistage smoothing,
performing, by the computer system, a multistage iterative optimization including successive alignment through multiple stages of smoothed data,
when results of the multistage iterative optimization are deemed not acceptable, adjusting at least one of a start depth, an end depth, and a current alignment function, and
when results of the multistage iterative optimization are deemed acceptable, outputting the aligned depth log, including aligned depth markers between the start depth and the end depth;
using the aligned depth log, determining, by the computer system, a stratigraphic depth of a bottom hole assembly (BHA) in a wellbore of the well during drilling; and
drilling a portion of the wellbore responsive to the stratigraphic depth of the BHA.