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Extensive development of shale gas has generated some concerns about environmental impacts such as the migration of natural gas into water resources. We studied high gas concentrations in waters at a site near Marcellus Shale gas wells to determine the geological explanations and geochemical implications. The local geology may explain why methane has discharged for 7 years into groundwater, a stream, and the atmosphere. Gas may migrate easily near the gas wells in this location where the Marcellus Shale dips significantly, is shallow (∼1 km), and is more fractured. Methane and ethane concentrations in local water wells increased after gas development compared with predrilling concentrations reported in the region. Noble gas and isotopic evidence are consistent with the upward migration of gas from the Marcellus Formation in a free-gas phase. This upflow results in microbially mediated oxidation near the surface. Iron concentrations also increased following the increase of natural gas concentrations in domestic water wells. After several months, both iron and SO42−concentrations dropped. These observations are attributed to iron and SO42−reduction associated with newly elevated concentrations of methane. These temporal trends, as well as data from other areas with reported leaks, document a way to distinguish newly migrated methane from preexisting sources of gas. This study thus documents both geologically risky areas and geochemical signatures of iron and SO42−that could distinguish newly leaked methane from older methane sources in aquifers.
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This content will become publicly available on June 16, 2026
The interplay between snow and polluted air masses in cold urban environments
Modeling of atmosphere–snow exchange provides insight into fundamental processes driving pollutant deposition. Gas properties, such as solubility and stickiness to ice, influence the role of the snowpack as a trace gas reservoir and chemical reactor.
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- PAR ID:
- 10634252
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Faraday Discussions
- Volume:
- 258
- ISSN:
- 1359-6640
- Page Range / eLocation ID:
- 502 to 520
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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