ABSTRACT

Air samples were collected in May and June 1995 from a gas and oil field area (Niigata) and areas of no known oil and gas deposits (Ibaraki and Gunma). The concentration of nonmethane hydrocarbons were measured. The concentration of ethane and propane in the air shows a positive correlation with ethylene regardless of the distance from the natural gas deposits. The correlation shows that emission from a natural gas deposit is not the major factor controlling atmospheric hydrocarbons. Automobile emission is considered to be a major source of ethane and propane because they correlate with acetylene, which is known to be mainly emitted from automobiles. A few samples collected in the vicinity of natural gas deposits shows high ethane and propane concentrations. This is presumed to be caused by emissions from oil and gas deposits.