Dataset Information

Geological CO₂ quantified by high-temporal resolution stable isotope monitoring in a salt mine.

ABSTRACT: The relevance of CO₂ emissions from geological sources to the atmospheric carbon budget is becoming increasingly recognized. Although geogenic gas migration along faults and in volcanic zones is generally well studied, short-term dynamics of diffusive geogenic CO₂ emissions are mostly unknown. While geogenic CO₂ is considered a challenging threat for underground mining operations, mines provide an extraordinary opportunity to observe geogenic degassing and dynamics close to its source. Stable carbon isotope monitoring of CO₂ allows partitioning geogenic from anthropogenic contributions. High temporal-resolution enables the recognition of temporal and interdependent dynamics, easily missed by discrete sampling. Here, data is presented from an active underground salt mine in central Germany, collected on-site utilizing a field-deployed laser isotope spectrometer. Throughout the 34-day measurement period, total CO₂ concentrations varied between 805 ppmV (5th percentile) and 1370 ppmV (95th percentile). With a 400-ppm atmospheric background concentration, an isotope mixing model allows the separation of geogenic (16-27%) from highly dynamic anthropogenic combustion-related contributions (21-54%). The geogenic fraction is inversely correlated to established CO₂ concentrations that were driven by anthropogenic CO₂ emissions within the mine. The described approach is applicable to other environments, including different types of underground mines, natural caves, and soils.

SUBMITTER: Frank AH

PROVIDER: S-EPMC7691992 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Geological CO2 quantified by high-temporal resolution stable isotope monitoring in a salt mine.

Frank Alexander H AH van Geldern Robert R Myrttinen Anssi A Zimmer Martin M Barth Johannes A C JAC Strauch Bettina B

Scientific reports 20201126 1

The relevance of CO2 emissions from geological sources to the atmospheric carbon budget is becoming increasingly recognized. Although geogenic gas migration along faults and in volcanic zones is generally well studied, short-term dynamics of diffusive geogenic CO2 emissions are mostly unknown. While geogenic CO2 is considered a challenging threat for underground mining operations, mines provide an extraordinary opportunity to observe geogenic degassing and dynami ...[more]

PMID: 33244124

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Geological CO₂ quantified by high-temporal resolution stable isotope monitoring in a salt mine.

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Geological CO<sub>2</sub> quantified by high-temporal resolution stable isotope monitoring in a salt mine.

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