* Have at least two of the three major groups of geochemical parameters (elemental, [[Wikipedia:Isotope geochemistry|isotopic]], molecular) support the positive correlation before it can be considered valid. (In the case of the NL oils, [[Wikipedia:Isotope geochemistry|isotopic]] and molecular data both support the correlation.) | * Have at least two of the three major groups of geochemical parameters (elemental, [[Wikipedia:Isotope geochemistry|isotopic]], molecular) support the positive correlation before it can be considered valid. (In the case of the NL oils, [[Wikipedia:Isotope geochemistry|isotopic]] and molecular data both support the correlation.) |