Method for correcting the measured concentrations of gas components in drilling mud

A method for using previously determined relative response factors for correcting gas trap values for gas components in a drilling mud, comprising:

• extracting a plurality of gas components from a volume of drilling mud comprising formation fluid and gases, while drilling;
• measuring a gas trap value for each gas components of interest;
• and
• calculating the corrected gas trap value for each of the gas components of interest by dividing each gas trap value by a previously determined relative response factor for each of the gas components of interest;
• wherein, the corrected gas trap value for each of the gas components of interest is utilized to calculate gas/oil ratios for characterizing formation fluids from the volume of drilling mud.

A system for automatically correcting a plurality of gas trap values, comprising:

• a data storage device having non-transitory computer readable data including mud logging data relating to the plurality gas trap values;
• a processor, configured and arranged to execute machine executable instructions stored in a processor accessible memory for performing a method comprising:
• acquiring a gas trap value for each gas component of interest;
• determining a gas trap response factor for each gas component of interest by dividing the gas trap value by a laboratory fluid analysis value for each gas component of interest;
• determining a relative response factor for each gas component of interest by dividing the gas trap response factor for each gas component of interest by the gas trap response factor for the gas component of interest with the lowest molecular weight;
• correcting the gas trap value for each gas component of interest by dividing the gas trap value by the relative response factor for each gas component of interest;
• and
• utilizing the corrected gas trap value for each gas component of interest to calculate gas/oil ratios for characterizing formation fluids.