CO2 efflux, soil temperature and carbon/helium isotope results from the Los Humeros geothermal field, Mexico

DOI

Magmatic volatiles can be considered as the surface fingerprint of active volcanic systems, both during periods of quiescent and eruptive volcanic activity. The spatial variability of gas emissions at Earth’s surface is a proxy for structural discontinuities in the subsurface of volcanic systems. We conducted extensive and regular spaced soil gas surveys within the Los Humeros geothermal field to improve the understanding of the structural control on fluid flow. Surveys at different scales were performed with the aim to identify areas of increased gas emissions on reservoir scale, their relation to unknown/knows volcano-tectonic structures on fault scale favoring fluid flow, and determine the origin of gas emissions. Herein, we show results from a carbon dioxide efflux scouting survey, which was performed across the main geothermal production zone together with soil temperature measurements. We identified five areas with increased carbon dioxide emissions, where further sampling was performed with denser sampling grids to understand the fault zone architecture and local variations in gas emissions. We show that a systematic sampling approach on reservoir scale is necessary for the identification and assessment of major permeable fault segments. The combined processing of CO2 efflux and carbon/helium isotopes facilitated the detection of permeable structural segments with a connection to the deep, high-temperature geothermal reservoir, also in areas with low to intermediate carbon dioxide emissions. The results of this study complement existing geophysical datasets and define further promising areas for future exploration activities in the north- and southwestern sector of the production field. The data are presented as one zip folder with 4 data tables (tab delimited text format) according to the measurement variable. The columns are defined in each data file.

Identifier
DOI https://doi.org/10.5880/GFZ.4.6.2020.001
Related Identifier https://doi.org/10.1016/j.jvolgeores.2020.106820
Related Identifier https://doi.org/10.1016/j.epsl.2008.07.051
Related Identifier https://doi.org/10.1016/S0883-2927(97)00076-0
Related Identifier https://doi.org/10.1017/S0016756899531774
Related Identifier https://doi.org/10.1016/0375-6742(74)90030-2
Metadata Access http://doidb.wdc-terra.org/oaip/oai?verb=GetRecord&metadataPrefix=oai_datacite&identifier=oai:doidb.wdc-terra.org:6819
Provenance
Creator Jentsch, Anna (ORCID: 0000-0001-7552-507X); Jolie, Egbert ORCID logo; Jones, David G.; Taylor-Curran, Helen; Zimmer, Martin; Peiffer, Loic ORCID logo; Lister, Bob
Publisher GFZ Data Services
Contributor Jentsch, Anna; Jolie, Egbert
Publication Year 2020
Funding Reference H2020 Energy, 727550; Consejo Nacional de Ciencia y Tecnología, 2015 04 268074
Rights CC BY 4.0; http://creativecommons.org/licenses/by/4.0/
OpenAccess true
Contact Jentsch, Anna (GFZ German Research Centre for Geosciences, Potsdam, Germany)
Representation
Language English
Resource Type Dataset
Format application/octet-stream
Size 2 Files
Discipline Geosciences
Spatial Coverage (-97.465W, 19.662S, -97.424E, 19.699N); Large-scale CO2 efflux survey; Area A; Area B; Area D; Area E