Toarcian and Bajocian ammonites from the Haushi-Huqf Massif of southwestern Oman and the Hawasina Nappes of the Oman Mountains: Implications for paleoecology and paleobiogeography
Bibliographic record
Abstract
ABSTRACT New and rare Jurassic ammonites have been found in Oman. A latest Bajocian Arabian Platform-type species was discovered in the Haushi-Huqf Massif autochthon of southwestern Oman, and Bajocian species typical of the Mediterranean Tethys and northwestern Europe were found in the Kawr-Misfah exotic unit of the Hawasina Nappes in the Oman Mountains. The dates provided by the new fauna have resulted in a reinterpretation of the geologic history of the containing rocks, and of their paleoecology and paleobiogeography. It is significant that ammonites from shallow-marine environments of the Arabian Platform are in close proximity to species from open-sea environments of the Mediterranean Tethys and northwestern Europe. This shows that endemism of the Arabian Province resulted from ecological isolation, whereas open-marine environments on the Oman margin, especially the pelagic seamounts off the margin, form part of a migration route between western and eastern Tethys (or Indo-Southwest Pacific), and perhaps far beyond. The occurrences among the Tethyan and pandemic components of ammonite faunas in the Canadian Pacific Cordillera of most of the taxa of the open-marine environments on the Oman margin reopens the question of Pacific biogeography during the Early Jurassic before the Hispanic oceanic corridor was completely open. Among the proposed models, the Pantropic Distribution Model of Newton is examined in the light of the Cretaceous paleobiogeography, with particular reference to rudists.
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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 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| 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".