Refining vanadium hyper‐enrichment in black shales of the Late Devonian–Early Mississippian Bakken Formation (USA)
Bibliographic record
Abstract
Abstract Vanadium hyper‐enrichment (V ≥ 500 μg g −1 ) is widespread in ancient marine organic‐rich sedimentary rocks and is controlled by its source and accumulation. To understand how V source and accumulation control V hyper‐enrichment, the V hyper‐enriched organic‐rich black shales of the Late Devonian–Early Mississippian Bakken Formation (USA) were investigated here. The results imply that V in the Bakken Formation black shales is mainly derived from detritus and open ocean. Its hyper‐enrichment was always related to the complexation of V(IV) species by organic matter and/or fine clay mineral adsorption, though extremely reducing (i.e. euxinic) depositional conditions sometimes assisted in accumulating V through forming V(IV)–sulphur structure and/or V(III). Vanadium is a frequently used seawater redox indicator, but its hyper‐enrichment in marine sediments/sedimentary rocks does not always need to be redox driven. This study, thus, reminds us to be more careful when reconstructing palaeoceanographic redox states using V‐involved proxies.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.003 | 0.000 |
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 teacher head, 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".