Provenance of the Lower Carboniferous Horton Group, Petit-de-Grat Island, Nova Scotia, as revealed by detrital zircon ages
Bibliographic record
Abstract
A quartz sandstone bed in a dominantly conglomeratic section in the central part of the Lower Carboniferous Horton Group on Petit-de-Grat Island, offshore southern Cape Breton Island, Nova Scotia, contains detrital zircon grains with ages ranging from mid-Devonian to Archean. The similarity of the Devonian and Neoproterozoic age spectrum to ages of igneous units in the adjacent Avalonian Mira terrane, in particular the Coastal belt, indicates that it was the main source area. This interpretation is supported by the similarity of the Neoproterozoic and older detrital zircon age spectrum to that of the detrital zircon age spectrum in a Cambrian sandstone unit from the Mira terrane. This interpretation indicates post-depositional dextral fault motion between the Isle Madame area and the Coastal belt.RésuméUne couche de grès quartzeux repérée dans une section principalement conglomératique dans la partie centrale du groupe de Horton du Carbonifère inférieur sur l’île Petit-de-Grat, au sud de l’île du Cap-Breton, en Nouvelle- Écosse, contient des grains de zircon détritique dont l’âge va du Dévonien moyen à l’Archéen. La similitude du spectre d’âge du Dévonien et du Néoprotérozoïque avec celui des unités ignées trouvées dans le terrane Mira d’Avalon adjacent, en particulier la ceinture côtière, indique qu’il s’agit de la région source principale. Cette interprétation est étayée par la similitude du spectre d’âge du zircon détritique du Néoprotérozoïque et de périodes plus anciennes avec celui du zircon détritique trouvé dans une unité de grès du Cambrien provenant du terrane Mira. Cette interprétation indique un mouvement postsédimentaire d’une faille dextre entre la région de l’île Madame et la ceinture côtière.[Traduit par la redaction]
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 | 0.001 |
| 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".