An atypical copper porphyry occurrence - A case study of the Hopper property, Yukon
Bibliographic record
Abstract
The main zone of mineralization is 1 km long and 0.5 km wide and is hosted in a granodiorite of calc alkaline affinity interpreted as the Ruby Range batholith. The granodiorite was emplaced in the Aishihik Metamorphic Suite rocks and is cut by younger mafic and felsic dykes. The mineralization consists of chalcopyrite and pyrite along fractures and as disseminations, and molybdenite that is associated with shearing. Sulphur isotopes from chalcopyrite and pyrite range from -1.7 to 0.7 per mil and are similar to sulphur isotopes from skarn samples collected from the same locality, indicating they are likely magmatic in origin. Alteration minerals associated with the mineralization at Hopper are mainly chlorite, epidoteclinozoisite, carbonate and titanite, i.e., the mineralization is dominantly associated with propylitic alteration. Forty-three samples of least altered and altered granodiorite were selected for whole rock analysis and mass balance calculations. The calculations show that altered granodiorite has lost SiO2, Na2O, K2O, Ba, Rb, and Cr, and gained in addition to Cu and Mo, FeO, Fe2O3, MgO, and CaO, Ti, and V. Conclusions The associations of copper mineralization with propylitic alteration and the loss of Si and K and gain in Fe, Mg and Ca indicate the system is not a typical copper porphyry system. The mass balance calculations and sulphur isotope data leads us to believe the copper has originated in a copper porphyry system possibly at depth or from a skarn mineralization and was transported to Hopper during a shearing event.
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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 | 0.002 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.001 | 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".