Petrogenesis of the 1.9 Ga mafic hanging wall sequence to the Flin Flon, Callinan, and Triple 7 massive sulphide deposits, Flin Flon, Manitoba, CanadaThis is a companion paper to DeWolfe, Y.M., Gibson, H.L., Lafrance , B., and Bailes, A.H. 2009. Volcanic reconstruction of Paleoproterozoic arc volcanoes: the Hidden and Louis formations, Flin Flon, Manitoba, Canada. Canadian Journal of Earth Sciences, <b>46</b>: this issue.
Bibliographic record
Abstract
A detailed study of the geochemical and isotopic characteristics of the volcanic rocks of the Hidden and Louis formations, which make up the hanging wall to the volcanogenic massive sulphide deposits at Flin Flon, Manitoba, was carried out on a stratigraphically controlled set of samples. The stratigraphy consists of the lowermost, dominantly basaltic, Hidden formation, and the overlying, dominantly basaltic, Louis formation. Of importance petrogenetically, is the 1920 unit a basaltic andesite with Nb/Thmn = 0.54–0.62, εNd(1.9Ga) = +3.6–+5.9, εHf(1.9Ga) = +8.5–+9.6, and 204Pb/206Pb = 23.9. The basaltic flows that dominate the Hidden formation have Nb/Thmn = 0.16–0.29, εNd(1.9Ga) = +1.7–+4.4, εHf(1.9Ga) = +7.0–+11.8 and 204Pb/206Pb = 16.9–18.6). The Carlisle Lake basaltic–andesite (top of Hidden formation) is characterized by Nb/Thmn = 0.16–0.14, and 204Pb/206Pb = 21.4. The rhyodacitic Tower member (bottom of Louis formation) has Nb/Thmn = 0.23, εNd1.9Ga = +4.6, εHf1.9Ga = +9.3, and 204Pb/206Pb = 22.2. The basaltic flows that dominate the Louis formation have Nb/Thmn = 0.18–0.25, εNd(1.9Ga) = +3.6–+4.2, εHf(1.9Ga) = +8.4–+11.3 and 204Pb/206Pb = 17.9. The Hidden and Louis formations show dominantly transitional arc tholeiite signatures, with the 1920 unit having arc tholeiite characteristics. It is interpreted to have formed through extensive fractional crystallization of differentiated magmas at shallow levels in oceanic crust. Given the geological, geochemical, and isotopic characteristics of the Hidden and Louis formations, they are interpreted to represent subducted slab metasomatism with minor contamination from subducted sediments.
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 | 0.002 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| 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 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".