Chemical species based selective dilution for analysis of a sub-formation sample

An apparatus, comprising:

• a first gas separation device, the first gas separation device comprising:
• a first intake device for receiving a gas sample from a formation, wherein the gas sample includes at least one first hydrocarbon identified for analysis;
• a first analysis processor configured to determine whether a concentration level of the at least one first hydrocarbon needs to be reduced to within a first analyzable range for the at least one first hydrocarbon,
• a first dilutant mass flow controller communicatively coupled with the first analysis processor, the first dilutant mass flow controller configured to, in response to a determination that the concentration level of the at least one first hydrocarbon needs to be reduced to within the first analyzable range, dilute, using a first amount of a dilutant, the gas sample to form a first diluted gas sample such that the concentration level of the at least one first hydrocarbon is reduced to within the first analyzable range;
• and
• a first column for separating out, from the first diluted gas sample, a subset of chemical species that includes the at least one first hydrocarbon;
• a second gas separation device, the second gas separation device comprising:
• a second intake device for receiving the gas sample from the formation, wherein the gas sample includes at least one second hydrocarbon identified for analysis;
• a second analysis processor configured to determine whether a concentration level of the at least one second hydrocarbon needs to be reduced to within a second analyzable range for the at least one second hydrocarbon,
• a second dilutant mass flow controller communicatively coupled with the second analysis processor, the second dilutant mass flow controller configured to, in response to the determination that the concentration level of the at least one second hydrocarbon needs to be reduced to within the second analyzable range, dilute, using a second amount of a dilutant, the same sample to form a second diluted gas sample such that the concentration level of the at least one second hydrocarbon is reduced to within the second analyzable range;
• and
• a second column for separating out, from the second diluted gas sample, a subset of chemical species that includes the at least one second hydrocarbon;
• and
• an analyzer configured to,
• analyze the subset of the chemical species that includes the at least one first hydrocarbon to measure an isotopic composition of the at least one first hydrocarbon;
• and
• analyze the subset of the chemical species that includes the at least one second hydrocarbon to measure an isotopic composition of the at least one second hydrocarbon.

A system, the system comprising:

• a gas sample valve for directing a gas sample from a formation into a gas chromatography system for analysis, wherein the gas sample includes at least one first hydrocarbon and at least one second hydrocarbon identified for analysis;
• a dilutant valve for directing a dilutant into the gas chromatography system;
• wherein the gas chromatography system includes:
• a first gas separation device, the first gas separation device comprising:
• a first intake device for receiving the gas sample from the gas sample valve, wherein the gas sample includes the at least one first hydrocarbon identified for analysis;
• a first analysis processor configured to determine whether a concentration level of the at least one first hydrocarbon needs to be reduced to within a first analyzable range for the at least one first hydrocarbon,
• a first dilutant mass flow controller communicatively coupled with the first analysis processor, the first dilutant mass flow controller configured to, in response to a determination that the concentration level of the at least one first hydrocarbon needs to be reduced to within the first analyzable range, dilute, using a first amount of a dilutant, the gas sample to form a first diluted gas sample such that the concentration level of the at least one first hydrocarbon is reduced to within the first analyzable range;
• and
• a first column for separating out, from the first diluted gas sample, a subset of chemical species that includes the at least one first hydrocarbon;
• a second gas separation device, the second gas separation device comprising:
• a second intake device for receiving the gas sample from the gas sample valve, wherein the gas sample includes the at least one second hydrocarbon identified for analysis;
• a second analysis processor configured to determine whether a concentration level of the at least one second hydrocarbon needs to be reduced to within a second analyzable range for the at least one second hydrocarbon,
• a second dilutant mass flow controller communicatively coupled with the second analysis processor, the second dilutant mass flow controller configured to, in response to the determination that the concentration level of the at least one second hydrocarbon needs to be reduced to within the second analyzable range, dilute, using a second amount of a dilutant, the same sample to form a second diluted gas sample such that the concentration level of the at least one second hydrocarbon is reduced to within the second analyzable range;
• and
• a second column for separating out, from the second diluted gas sample, a subset of chemical species that includes the at least one second hydrocarbon;
• and
• an analyzer configured to,
• analyze the subset of the chemical species that includes the at least one first hydrocarbon to measure an isotopic composition of the at least one first hydrocarbon;
• and
• analyze the subset of the chemical species that includes the at least one second hydrocarbon to measure an isotopic composition of the at least one second hydrocarbon.