Fugitive Methane Forensics
Oral Presentation
Prepared by A. Jeffrey
Zymax Forensics, 600 S. Andreasen Ave, Suite B, Escondido, CA, 92026, United States
Contact Information: alan.jeffrey@zymaxusa.com; 760-781-3338
ABSTRACT
Methane gas seeping out of the ground is a widespread phenomenon. Marsh gas bubbling up in swampy areas is easily observed and is a natural feature of the environment. In areas not close to estuaries or swamps, methane seeps are less obvious, and may originate from human activities. Fugitive methane can pose various levels of concern. In small concentrations it may be an aesthetic concern, characterized by unpleasant smells resulting from associated volatile compounds. At concentrations above 5%, methane can be ignited by flames and sparks, and if confined, can cause explosions.
Identifying the source of the methane is important in mitigating these effects. Methane can be formed biologically (biogenic) and chemically (thermogenic). These processes can be distinguished by a combination of hydrocarbon composition, methane carbon and hydrogen isotopic ratios, and methane radiocarbon concentrations.
Case studies will be presented to show how these techniques were used to investigate methane explosions, gas seeps in oil producing areas, landfill gas seeps, and gas pipeline leaks.
Oral Presentation
Prepared by A. Jeffrey
Zymax Forensics, 600 S. Andreasen Ave, Suite B, Escondido, CA, 92026, United States
Contact Information: alan.jeffrey@zymaxusa.com; 760-781-3338
ABSTRACT
Methane gas seeping out of the ground is a widespread phenomenon. Marsh gas bubbling up in swampy areas is easily observed and is a natural feature of the environment. In areas not close to estuaries or swamps, methane seeps are less obvious, and may originate from human activities. Fugitive methane can pose various levels of concern. In small concentrations it may be an aesthetic concern, characterized by unpleasant smells resulting from associated volatile compounds. At concentrations above 5%, methane can be ignited by flames and sparks, and if confined, can cause explosions.
Identifying the source of the methane is important in mitigating these effects. Methane can be formed biologically (biogenic) and chemically (thermogenic). These processes can be distinguished by a combination of hydrocarbon composition, methane carbon and hydrogen isotopic ratios, and methane radiocarbon concentrations.
Case studies will be presented to show how these techniques were used to investigate methane explosions, gas seeps in oil producing areas, landfill gas seeps, and gas pipeline leaks.
