Middle Cenomanian (Late Cretaceous) molluscs of the Shaftesbury Formation, Birch Mountains, northeastern Alberta, Canada
Bibliographic record
Abstract
Historical Resources Impact Assessment and Mitigation studies have documented a new middle Cenomanian invertebrate fauna from the Shaftesbury Formation in the Birch Mountains, northwest of Fort McMurray, in northeastern Alberta, Canada. Although older portions (Albian) of the Shaftesbury Formation in Alberta and British Columbia have yielded invertebrate fossils, this is the first fauna of middle Cenomanian age known for the unit. The fauna includes the ammonites Acanthoceras wyomingense and Borissjakoceras orbiculatum, the inoceramid bivalves Inoceramus dunveganensis and Inoceramus prefragilis stephensoni, and the gastropod Pirsila tensa. The occurrence of the late middle Cenomanian zonal fossil A. wyomingense allows correlation between the middle “Fish Scales Formation” of the Shaftesbury Formation and the lower part of the Labiche Formation of Alberta, and with five units farther to the south in the United States, namely the Greenhorn Limestone, Lincoln Formation, and Graneros Shale of Kansas, the Frontier Formation of Wyoming, and the Belle Fourche Shale of Montana.
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 | 0.002 |
| Science and technology studies | 0.002 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 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".