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Updated: Jun 26, 2026
08:18
Design and Use of a Full Flow Sampling System (FFS) for the Quantification of Methane Emissions
Published on: June 12, 2016
Earth's degassing: a missing ethane and propane source.
Giuseppe Etiope1, Paolo Ciccioli
1Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma 2, via V. Murata 605, 00143 Rome, Italy. Etiope@ingv.it
Science (New York, N.Y.)
|January 24, 2009
Summary
Natural geologic seepage, including from geothermal and volcanic areas, is a significant source of atmospheric ethane and propane. Earth's degassing accounts for at least 17% of ethane and 10% of propane emissions, helping to balance global budgets.
Area of Science:
- Geochemistry and Atmospheric Science
Background:
- Global atmospheric budgets for ethane (C2H6) are unbalanced, indicating a missing source.
- Current emission inventories do not fully account for all sources of atmospheric hydrocarbons.
Purpose of the Study:
- To identify the "unknown" source contributing to atmospheric ethane budgets.
- To quantify the contribution of natural geologic seepage to atmospheric ethane and propane (C3H8) concentrations.
Main Methods:
- Analysis of methane (CH4), ethane, and propane concentrations in surface gas emissions from 238 diverse geographic and geologic sites.
- Integration of published geomethane emission estimates.
Main Results:
- Natural gas seepage from petroliferous, geothermal, and volcanic areas is identified as a substantial missing source.
- Earth's degassing accounts for at least 17% of total ethane emissions.
- Earth's degassing accounts for at least 10% of total propane emissions.
Conclusions:
- Geologic sources play a significant role in the global atmospheric budgets of ethane and propane.
- Natural gas seepage is a key contributor to atmospheric hydrocarbon levels, helping to resolve discrepancies in current emission inventories.
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