Petroleum Geochemistry Division – Gas Analysis...

GEOTECH has extensive experience in compositional and isotopic analyses of hydrocarbon and non-hydrocarbon components of natural gas. Data derived from natural gas analyses are invaluable for gas-source rock, gas-oil and gas-gas correlation studies and for distinguishing between gas families and evaluating gas reservoir continuity.

Compositional Analysis

Compositional analysis of gases includes both hydrocarbon (C1 to C5+) and non-hydrocarbon (nitrogen, oxygen and carbon dioxide) components via GC-FID. Hydrogen and helium concentrations can be determined via GC-TCD. GEOTECH’s capabilities in gas analysis also include determination of organic and inorganic sulfur compounds such as hydrogen sulfide and mercaptans by GC-FPD. Compositional data can provide substantial information about:

      Source of gaseous hydrocarbons (biogenic vs thermogenic)
      Level of gas maturity
      Evidence for alteration via mixing and/or biodegradation

Stable Carbon Isotopic Composition (CSIA)

GEOTECH’s CSIA protocol enables determination of the individual isotopic composition of C1 to C5+ hydrocarbons as well as nitrogen and carbon dioxide, if present in significant relative abundance. Isotopic data can be used in conjunction with compositional data for source and maturity evaluation. In addition, CSIA data can help answer questions such as:

      Does the gas derive from humic or sapropelic kerogen?
      Has the gas been altered by biodegradation?
      Has the gas been generated from a single source rock?
      Are two or more gases genetically related?