The genesis of the Gayna River carbonate-hosted Zn-Pb deposit, Northwest Territories
Bibliographic record
Abstract
The Gayna River deposit is located in the Mackenzie \nMountains of NW Canada and is hosted by the platform \ncarbonates of the Neoproter ozoic Little Dal Group. The mineralization occurs as a series of sphalerite cemented breccias and veins which have \na clear structural control. The deposits at Gayna have the following main paragenetic components: pre-ore (pyrite, limestone, dolostone, calcite \ncement and early sphalerite), ore-related (dolos\npar, quartz, sphalerite, and galena) and post-ore (quartz, pyrite, calcite, and pyrobitumen). In total the δ 34 S composition of sulphides at Gayna River range from -4.4 to 25.7‰ (CDT). The pre-ore phase pyrite and sphalerite samples have the lower δ 34 S values (-4.4 to 2.4‰ and 1.5 to 5.2‰ respectively). Carbon and oxygen isotope results for the host dolomite were δ 13 C = 1.8 to 4.6‰ (PDB) and δ 18 O = 22.1 to 25.2‰ (SMOW). The ore-phase sphalerite has δ 34 S values from 12.2 to 25.7‰ and the galena ranges from δ 34 S = 14.9 to 23.2‰. The dolospar phase has δ 13 C values of 0.7 to 2.5‰ (PDB) and δ 18\nO values of 20.0 to 26.6‰ (SMOW). Primary fluid inclusion data in sphalerite suggest the main phase of mineralization was formed by fluids that ranged in homogenization temperature (Th) from 107 to 227°C (mean 204°C) and 23.0 to 34.4 wt.% NaCl equiv. Pyrites from the post-ore phase have δ 34\nS values of 11.5 to 21.2‰. The late calcite phase had δ 13\nC values of -3.0 to 3.0‰ (PDB) and δ 18 O values of 16.6 to 20.3‰ (SMOW). Inclusions in late quartz and calcite have Th values that range from 99 to 233°C and 59 to 159°C respectively and corresponding salinities of 13.7 to 32.9 wt % NaCl equiv. for quartz, and 13.6 to 23.7 % NaCl equiv for calcite. The data suggests that the Gayna River deposit likely was formed by mixing of at least two \nfluids and one of those fluids originated as seaw\nater. The sulphur for the deposit was derived from the evaporite sequences found in the Little Dal \nGroup possibly by thermochemical sulphate reduction. Post-mineralization fluids are cooler and less saline, possibly due to the mixing of the mineralizing brine with a more dilute fluid.
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 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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".