Implications of Microbial Redox Catalysis in Analogue Systems for Repository Safety Cases
Bibliographic record
Abstract
A detailed assessment of studies of oxidising redox fronts around fractures at depth in otherwise “reducing” environments suggests that the usual explanation, in terms of past disturbances that have resulted in deep penetration of oxidising water, are incompatible with hydrogeological and/or geochemical observations. An alternative hypothesis, microbial catalysis of kinetically slow or hindered reactions involving oxyanions such as sulphate or carbonate, appears potentially more credible. Although still not always taken into account by the geochemical community, the role of microbial metabolism in low temperature geochemistry is supported by the rapidly expanding database on subsurface microbial populations. These populations are demonstrated to be viable and, therefore, could potentially be active at levels close to or below current detection limits in deep geological systems. Indeed, inspection of information available from several analogue studies or repository site characterisation programmes suggests that such activity may explain some of the geochemical anomalies encountered. This paper examines the current (indirect) evidence for microbial redox catalysis in relevant subsurface rock matrix environments and considers the implications that this would have for the development of site understanding — and in particular the identification of factors that may distinguish between different locations during site selection. Further, it examines the wider implications of more extensive roles of microbes in repository systems on the overall post-closure safety case and the need for further focused analogue studies to develop answers to these open questions.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.009 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.002 |
| Scholarly communication | 0.002 | 0.002 |
| Open science | 0.001 | 0.002 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.006 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".