Methane, Ethane, and Propane Concentrations in Gulf of Mexico: GEOLOGICAL NOTES

Abstract

The concentrations of the low-molecular-weight hydrocarbons in the Gulf of Mexico were measured. The ranges of methane, ethane, and propane were found to be (6-125)×10-5, (1.6-37.3)×10-6, and (1.2-38.6)×10-6 ml/liter seawater, respectively, for depths ranging from zero to 3,742 m. For a given water column, these values were found to be in the same range as, but more variable than, those previously reported. These results suggest that one method of offshore petroleum-seep detection is to survey and map the concentrations of hydrocarbons in near-bottom waters.