Patent ID: 11860137
Assignee: SAUDI ARABIAN OIL COMPANY
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. A method for detecting the presence of natural hydrocarbon compounds in drilling cuttings, the method comprising:
introducing a synthetic chemical standard having a known concentration to an oil-based drilling fluid;
producing a tagged oil-based drilling fluid;
using gas chromatography-mass spectroscopy, determining a concentration of hydrocarbon compounds present in the tagged oil-based drilling fluid, wherein the concentration corresponds to a first hydrocarbon signal;
circulating the tagged oil-based drilling fluid in a borehole during drilling;
recovering drilling cuttings mixed with the tagged oil-based drilling fluid from the borehole;
extracting hydrocarbon compounds from the drilling cuttings;
using gas chromatography-mass spectroscopy, determining a concentration of hydrocarbon compounds present in the drilling cuttings that were mixed with the tagged oil-based drilling fluid, wherein the concentration corresponds to a second hydrocarbon signal; and
based on the difference between the first hydrocarbon signal and the second hydrocarbon signal, determining an initial concentration of natural hydrocarbons in the drilling cuttings prior to mixing with the tagged oil-based drilling fluid.