US 12,282,136 B2
Downhole lithium detection systems and methods
Christian Stoller, Neuenhof (CH)
Assigned to SCHLUMBERGER TECHNOLOGY CORPORATION, Sugar Land, TX (US)
Filed by Schlumberger Technology Corporation, Sugar Land, TX (US)
Filed on Sep. 22, 2023, as Appl. No. 18/472,435.
Prior Publication US 2025/0102699 A1, Mar. 27, 2025
Int. Cl. G01N 23/222 (2006.01); G01N 23/2208 (2018.01); G01V 5/04 (2006.01); G01V 5/10 (2006.01); G01V 5/22 (2024.01)
CPC G01V 5/102 (2013.01) [G01N 23/2208 (2013.01); G01N 23/222 (2013.01); G01V 5/045 (2013.01); G01V 5/234 (2024.01); G01N 2223/0745 (2013.01); G01N 2223/1066 (2013.01); G01N 2223/507 (2013.01); G01N 2223/616 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A system comprising:
one or more downhole tools, wherein a first downhole tool of the one or more downhole tools comprises:
a pulsed neutron generator configured to emit neutrons into a borehole of a geological formation;
one or more first gamma-ray detectors configured to obtain a first measurement of gamma-ray emissions of a borehole environment, the gamma-ray emissions induced by the neutrons emitted from the pulsed neutron generator; and data processing circuitry configured to:
determine a Sigma value associated with the borehole environment based on the first measurement;
determine a plurality of elemental concentrations of a corresponding plurality of elements based on one or more gamma-ray energy spectra obtained via the one or more downhole tools, wherein the plurality of elements excludes lithium;
determine an elemental Sigma contribution of the plurality of elements based on the plurality of elemental concentrations of the corresponding plurality of elements;
determine a lithium Sigma contribution based on a difference between the Sigma value and the elemental Sigma contribution of the plurality of elements; and
determine a lithium concentration within the borehole environment based on the lithium Sigma contribution.