Assessment of the level of activity of advective transport through fractures and faults in marine deposits by comparison between stable isotope compositions of fracture and pore waters

Mochizuki, Akihito; Ishii, Eiichi

doi:10.1007/s10040-022-02466-9

Cited by 8 publications

(5 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Assuming inter-site transport was possible, environmental heterogeneity could have precluded colonization by transported organisms. Thus, we attribute the genomic homogeneity within the Horonobe URL in part to consistent and stable geochemical and physical environments (as revealed by in situ measurements; Miyakawa et al, 2017; Sasamoto et al, 2015; Mochizuki & Ishii, 2022; 2023). The finding of biological stability is important for assessment of engineered subsurface environments, and thus long-term confinement of radioactive waste.…”

Section: Discussionmentioning

confidence: 78%

“…This raises the question of whether genotype overlaps across sites can be explained by groundwater-mediated microbial transport. Comparison of d 18 O and dD between pore water and pumped groundwater indicates that there are “active” and “inactive” zones of groundwater flow within the Horonobe URL (Mochizuki et al, 2022). The groundwater samples collected for microbiology analyses are from “inactive” regions ( Fig.…”

Section: Discussionmentioning

confidence: 99%

“…Alternatively, it is possible that microbial dispersal occurred under conditions that differ from the present. H and O stable isotopic measurements indicate that meteoric water was intruded into the Horonobe subsurface during glaciation (likely the Last Glacial Stage, between 12,000 and 70,000 years ago), when hydraulic gradients were higher than at present (Teramoto et al, 2010; Ishii, 2018; Nakata et al, 2018; Mochizuki & Ishii, 2022). Intrusion of meteoric water probably ceased when hydraulic gradients decreased due to sea level rise (Hanatani et al, 2010).…”

Section: Discussionmentioning

confidence: 99%

“…The relationship between d 18 O and dD in pore water and groundwater collected from the Horonobe URL (modified from Mochizuki & Ishii, 2022). Based on the comparison of d 18 O and dD between pore water and pumped groundwater, “active” and “inactive” zones of advective flow of meteoric water through fractures at present are suggested for the Horonobe samples (colored circles).…”

Section: Supplementary Informationmentioning

confidence: 99%

See 3 more Smart Citations

Characterization of sediment and granite hosted deep underground research laboratories reveals diverse microbiome functions, limited temporal variation and substantial genomic conservation

Amamo,

Sachdeva,

Gittins

et al. 2024

Preprint

Self Cite

View full text Add to dashboard Cite

Underground research laboratories (URLs) provide a window on the deep biosphere and enable investigation of potential microbial impacts on nuclear waste, CO2 and H2 stored in the subsurface. We carried out the first multi-year study of groundwater microbiomes sampled from defined intervals between 140 and 400 m below the surface of the Horonobe and Mizunami URLs, Japan. We reconstructed draft genomes for >90% of all organisms detected over a four year period. The Horonobe and Mizunami microbiomes are dissimilar, likely because the Mizunami URL is hosted in granitic rock and the Horonobe URL in sedimentary rock. Despite this, hydrogen metabolism, rubisco-based CO2 fixation, reduction of nitrogen compounds and sulfate reduction are well represented functions in microbiomes from both URLs, although methane metabolism is more prevalent at the organic- and CO2-rich Horonobe URL. High fluid flow zones and proximity to subsurface tunnels select for candidate phyla radiation bacteria in the Mizunami URL. We detected near-identical genotypes for approximately one third of all genomically defined organisms at multiple depths within the Horonobe URL. This cannot be explained by inactivity, as in situ growth was detected for some bacteria, albeit at slow rates. Given the current low hydraulic conductivity and groundwater compositional heterogeneity, ongoing inter-site strain dispersal seems unlikely. Alternatively, the Horonobe URL microbiome homogeneity may be explained by higher groundwater mobility during the last glacial period. Genotypically-defined species closely related to those detected in the URLs were identified in three other subsurface environments in the USA. Thus, dispersal rates between widely separated underground sites may be fast enough relative to mutation rates to have precluded substantial divergence in species composition. Species overlaps between subsurface locations on different continents constrain expectations regarding the scale of global subsurface biodiversity. Overall, microbiome and geochemical stability over the study period has important implications for underground storage applications.

show abstract

Section: Discussionmentioning

confidence: 78%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Supplementary Informationmentioning

confidence: 99%

See 2 more Smart Citations

Characterization of sediment and granite hosted deep underground research laboratories reveals diverse microbiome functions, limited temporal variation and substantial genomic conservation

Amamo,

Sachdeva,

Gittins

et al. 2024

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

“…Miyakawa et al discussed the origin of groundwater in the Horonobe region as modern meteoric water, fossil meteoric, and seawater. Mochizuki and Ishii also reported that intrusion of modern meteoric water into the depth of the experimental galleries of the URL is limited due to the glacial–interglacial difference in hydraulic gradients. This suggests that the terrestrial humic-like P2 and 3 of the PARAFAC decomposition in this study are derived by the recharge of meteoric water during a glacial period after 1.0 Ma.…”

Section: Discussionmentioning

confidence: 97%

Origin of Dissolved Organic Matter in Deep Groundwater of Marine Deposits and Its Implication for Metal Binding

Saito,

Nishi,

Amano

et al. 2023

ACS EST Water

View full text Add to dashboard Cite

Biofilm Formation on Excavation Damaged Zone Fractures in Deep Neogene Sedimentary Rock

Hirota,

Kouduka,

Fukuda

et al. 2024

Microb Ecol

View full text Add to dashboard Cite

Deep underground galleries are used to access the deep biosphere in addition to mining and other engineering applications, such as geological disposal of radioactive waste. Fracture networks developed in the excavation damaged zone (EDZ) are concerned with accelerating mass transport, where microbial colonization might be possible due to the availability of space and nutrients. In this study, microbial biofilms at EDZ fractures were investigated by drilling from a 350-m-deep gallery and subsequent borehole logging at the Horonobe Underground Research Laboratory (URL). By using microscopic and spectroscopic techniques, the dense colonization of microbial cells was demonstrated at the surfaces of the EDZ fractures with high hydraulic conductivity. 16S rRNA gene sequence analysis revealed the dominance of gammaproteobacterial lineages, the cultivated members of which are aerobic methanotrophs. The near-complete genomes from Horonobe groundwater, affiliated with the methanotrophic lineages, were fully equipped with genes involved in aerobic methanotrophy. Although the mediation of aerobic methanotrophy remains to be demonstrated, microbial O2 production was supported by the presence of genes in the near-complete genomes, such as catalase and superoxide dismutase that produce O2 from reactive oxygen species and a nitric oxide reductase gene with the substitutions of amino acids in motifs. It is concluded that the EDZ fractures provide energetically favorable subsurface habitats for microorganisms.

show abstract

Assessment of the level of activity of advective transport through fractures and faults in marine deposits by comparison between stable isotope compositions of fracture and pore waters

Cited by 8 publications

References 51 publications

Characterization of sediment and granite hosted deep underground research laboratories reveals diverse microbiome functions, limited temporal variation and substantial genomic conservation

Characterization of sediment and granite hosted deep underground research laboratories reveals diverse microbiome functions, limited temporal variation and substantial genomic conservation

Origin of Dissolved Organic Matter in Deep Groundwater of Marine Deposits and Its Implication for Metal Binding

Biofilm Formation on Excavation Damaged Zone Fractures in Deep Neogene Sedimentary Rock

Contact Info

Product

Resources

About