Cenozoic ichthyolith biostratigraphy: Tofino Basin, British Columbia
Bibliographic record
Abstract
Five new late Eocene Pliocene ichthyolith zones are defined based on indigenous faunal occurrences in strata that outcrop along western Vancouver Island and samples from six offshore Tofino Basin wells. Five new interval zones are each defined based on distinct transported ichthyolith assemblages. Results are correlated within the framework of established Cenozoic west coast and Arctic foraminifer zones and ichthyolith occurrences in deep-sea core samples and Cretaceous Queen Charlotte Group and Nanaimo Group strata of coastal British Columbia. The use of multiple data sets was important to interpret complex active tectonic margin sedimentation and structures. The integrated ichthyolith and foraminifer biostratigraphy allowed an interpretation of well log data and lithology reports. Also, we reassessed previous offshore seismic data, evaluated fossil preservation and thermal alteration, and distinguished transported from indigenous ichthyolith occurrences. These data allowed a reinterpretation of tectonic segments and associated strata of the Pacific Rim and Crescent terranes and the Cascadia Accretionary Complex onshore and offshore Vancouver Island. Tectonically active phases during the Eocene and Oligocene early Miocene resulted in transport of Cretaceous to Eocene ichthyoliths from structural highs to lows, indicating proximity of the Pluto I-87 and Zeus D-14 wells to the Tofino Fault between the Pacific Rim and Crescent terranes and suggesting derivation with coeval Hesquiat Peninsula strata. An unconformity above the Eocene Crescent Formation volcanics in Prometheus H-68 and Zeus D-14 wells is correlated with the Pluto I-87 and Apollo J-14 well stratigraphy. An upper Miocene unconformable surface coincides with accretion and uplift of the Cascadia Accretionary Complex.
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 | 0.003 | 0.004 |
| Science and technology studies | 0.002 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.007 | 0.001 |
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".