Carbonate sedimentology of enigmatic limestone beds in the Pennsylvanian Joggins Formation, Nova Scotia, Canada
Bibliographic record
Abstract
The Joggins Fossil Cliffs of Nova Scotia, Canada, is one of the best- exposed Carboniferous successions in the world. Intense study over the past 150 years has provided important information about coal- forming and fluvial processes in well preserved strata. A longstanding question is the extent to which marine conditions influenced sedimentation. Understanding this influence is important because seawater salinity is a primary control on vegetation type, and thus coal production in coastal environments. The investigation of limestone beds in the Joggins Formation provides a new perspective on the depositional environments in which coal was produced. Limestone beds are 15 to 100 cm thick and contain ostracodes, bivalves, and echinoderm fragments. They occur primarily within cyclothems at the base of the Joggins Formation interbedded with coal and flood plain deposits. The antithetic relationship in the abundance of ostracodes and bivalves through the thickness of the Joggins Formation, as well as the presence of echinoderms, is interpreted to reflect a gradual transition from marine to fluvial conditions with time. Examination of limestone with cathodoluminescence further reveals that maximum burial depths were probably no more than 60 to 80 m, which is much shallower than recent published estimates. Future work should couple these new findings with vitrinite reflectance data from coals to more completely understand burial history.
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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 | 0.001 | 0.002 |
| Science and technology studies | 0.002 | 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) | 0.002 | 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".