Low-temperature formation of hydrocarbon gases in San Francisco Bay sediment (California, U.S.A.)
To understand the processes responsible for the presence of low-molecular-weight hydrocarbons (C1-C4) in anoxic environments, we studied sediments collected from an anaerobic estuarine mudflat. In these sediments methane (C1) was several orders of magnitude more abundant than all other C2-C4 hydrocarbons; the C1 (C2 + C3) ratio was ??? 13,000. Mean ethane/ethene and propane/propene ratios were 0.4 and 0.7, respectively. Production of C1-C4 hydrocarbons was monitored during prolonged incubation (7 months) of sediments at 27?? and 4??C. Samples stored at 27??C generated significant quantities of C1-C4 hydrocarbon gases. Incubation at 4??C inhibited production of these gases. Several bactericides were tested with respect to their ability to inhibit formation of gaseous hydrocarbons. Sodium azide, chloroform, and 2-bromoethanesulfonic acid effectively inhibited methane formation, but not ethene formation in dilute continuously-shaken sediment slurries. Zephiran chloride only caused partial inhibition of methanogenesis (46%) and ethene generation (34%) in these slurries. In experiments with more concentrated unshaken sediment slurries, however, zephiran chloride and sodium azide did not block formation of methane, ethane, or propane. Only storage at -10??C prevented production of these gases. These results indicate that C1-C4 hydrocarbons can be formed by low-temperature reactions, possibly mediated by microorganisms. ?? 1982.
Citation Information
Publication Year | 1982 |
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Title | Low-temperature formation of hydrocarbon gases in San Francisco Bay sediment (California, U.S.A.) |
DOI | 10.1016/0009-2541(82)90084-5 |
Authors | T.M. Vogel, R.S. Oremland, K. A. Kvenvolden |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Chemical Geology |
Index ID | 70011490 |
Record Source | USGS Publications Warehouse |
USGS Organization | San Francisco Bay-Delta; Pacific Regional Director's Office |