Metal transport by liquid hydrocarbons: evidence from metalliferous shale and pyrobitumen, Yukon
Bibliographic record
Abstract
Hyper-enriched black shale (HEBS) occurs within Yukon Devonian stratigraphy as a thin (approximately 3 cm thick) laterally extensive (100-1000s km2) sulphide-rich unit. These shale beds contain an average of 4 weight % Ni, 0.5 weight % Zn, and 0.3 weight % Mo, as well as anomalous concentrations of Cu, Ag, Se, As, P, Ba, U, platinum group and rare earth elements. The origin of these HEBS deposits is strongly debated; possible mechanisms include metals being derived from seawater in a sediment-starved, stratified euxinic basin or by addition from hydrothermal fluids. However, a process that has not been considered is mobilization of metals by hydrocarbon liquids. These liquids are produced during diagenesis, and are capable of transporting nickel, vanadium and zinc. Pyrobitumen occurs as centimetre-scale veins within the hyper-enriched black shale (HEBS) layer, but also much thicker metre-wide veins in the surrounding shale packages. Bulk analysis shows that these veins have high metal concentrations; most notably nickel and vanadium. Pyrobitumen within the HEBS horizon has average Ni and V concentrations of 1300 ppm and 1400 ppm, respectively. A vein above the HEBS horizon has 2000 ppm Ni and 3700 ppm V, as well as 8000 ppm Zn and 220 ppm Mo. Nickel-vanadium sulphur phases are present within the organic material as small (2-10 micrometres long) laths. The presence of nickel- and vanadium-bearing phases within pyrobitumen veins is consistent with the notion of metal-transportation by liquid hydrocarbons.
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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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 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".