Mise en évidence d’une nouvelle unité pyroclastique viséenne dans la partie centrale de l’île d’Ouessant (Massif armoricain)
Bibliographic record
Abstract
The southern sector of the Ouessant island (Armorican Massif) was previously interpreted as a Visean underwater volcano[1]sedimentary basin, deformed during the Variscan orogenesis, while the northern part is entirely plutonic and younger (Gzhelian). The southern part of the island would therefore be the equi[1]valent of the Centre-Armorican basins of Châteaulin and Laval. The Ouessant central magmatic unit was until now ascribed to the northern sector and considered as a tectonically crushed pluton, equivalent to the Aber-Ildut porphyritic granite (Leon). Consequently, this magmatic body was integrated into the late-Hercynian North Armorican “red granite” belt. We bring here new elements showing that this unit is in fact purely volcanic and therefore included within the southern sector of the island. The presence of basal columnar joints, the peperitic nature of the contact with metasediments and some structural characteristics of porphyritic quartz clasts attest that it was an ignimbrite-type pyroclastic unit, fragmented under high tempe[1]rature. After a mafic episode, the South-Ouessant volcanism, become felsic, alternated effusive and explosive stages, with two major pyroclastic episodes. The numerous homogeneous granite clasts present in the breccia are probably originating from a granitic body underlying the volcanic system.\n
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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 | 0.001 |
| 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 | 0.001 |
| Scholarly communication | 0.002 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.002 | 0.001 |
| 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".