US 11,939,863 B2
Distributed acoustic sensing systems and methods with dynamic gauge lengths
Eric Davis, San Francisco, CA (US); Mikko K. Jaaskelainen, Houston, TX (US); and Joshua Brandt Stokes, Denver, CO (US)
Assigned to Halliburton Energy Services, Inc., Houston, TX (US)
Filed by Halliburton Energy Services, Inc., Houston, TX (US)
Filed on Oct. 1, 2021, as Appl. No. 17/492,097.
Prior Publication US 2023/0108047 A1, Apr. 6, 2023
Int. Cl. E21B 47/14 (2006.01); E21B 49/00 (2006.01)
CPC E21B 47/14 (2013.01) [E21B 49/003 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A method comprising:
deploying an optical fiber attached to a distributed acoustic sensing (DAS) interrogator in a wellbore;
pre-setting gauge length of the DAS interrogator based on an expected measurement signal;
interrogating the optical fiber using the DAS interrogator;
receiving reflected DAS signals along a length of the optical fiber using the pre-set gauge length;
performing, by a processor, an analysis to estimate a magnitude of a strain source associated with the reflected DAS signals and wavelength of measured strain signals along the optical fiber; and
dynamically adjusting the gauge length for at least a portion of the optical fiber within a pre-defined limit of the DAS interrogator as a function of a distance from the optical fiber to a closest strain source based on the estimated magnitude and wavelength.