The Missisauga to Logan Canyon formation transition: Early Cretaceous dinoflagellate cyst bioevents from Panuke B-90 well, Scotian Margin (offshore Atlantic Canada)
Bibliographic record
Abstract
Due to the rapid evolution of dinoflagellates, their fossil cysts are reliable age markers in the Mesozoic and Cenozoic. The Scotian Margin contains a well-developed succession of Mesozoic strata that accumulated during the opening of the North Atlantic Ocean. We focus on Lower Cretaceous conventional cores 4 to 13 from the Panuke B-90 well, which yield significant dinoflagellate cyst (dinocyst) assemblages. Four intervals from the section are defined based on associated lithologies, and in each interval the palynological assemblages broadly reflect changes in paleoenvironmental setting. Dinocyst occurrences and associated key bioevents are used to refine age. In the marginal marine Interval 1, the co-occurrence of Odontochitina operculata and Tenua anaphrissa and the first occurrence (FO) of Pseudoceratium retusum indicate an early Barremian age. Above the dominantly terrestrial Interval 2, the FOs of Palaeoperidinium cretaceum and Cerbia tabulata suggest a late Barremian age for the terrestrial to marine Interval 3. Near the boundary between Interval 3 and marine Interval 4, a Cerbia tabulata acme and the FO of Aptea cf. polymorpha, as well as the last occurrence (LO) of Muderongia microperforata, confirm an early Aptian age. Accordingly, the Upper Member of the Missisauga Formation is Barremian to lower Aptian and the overlying Naskapi Member of the Logan Canyon Formation is lower Aptian; the presence of the early Aptian ammonite Deshayesites provides further age constraint. The key dinocyst bioevents f rom Panuke B-90 conventional cores are an important contribution to the ongoing Mesozoic event-stratigraphic framework for the Scotian Margin.
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 distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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 teacher head, 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".