Carbon isotope systematics of individual hydrocarbons in hydrothermal petroleums from the Guaymas Basin, Gulf of California

Individual aliphatic and aromatic hydrocarbons in hydrothermal petroleums from the Guaymas Basin were subjected to compound specific isotope analysis to trace their origins. The carbon isotope compositions of the alkanes and polycyclic aromatic hydrocarbons (means −23.1 and −21.2%, respectively) all reflect their marine source and confirm their generation from the sedimentary kerogen.