Sedimentation of the Phyllopod Bed within the Cambrian Burgess Shale Formation of British Columbia
Bibliographic record
Abstract
We provide the most detailed sedimentological log to date through the Phyllopod Bed of the mid-Cambrian Burgess Shale Formation of British Columbia, based on millimetre-scale logging of a suite of thin sections. The sedimentary facies is dominated by alternations of homogeneous mudstone and a coarser-grained, laminated, variably sandy and shelly mudstone that is locally micronodular. Most boundaries between these two lithologies are gradational, and discrete fining-upwards turbidite units were rarely recognized. Such a pattern is interpreted to indicate rapid sedimentation of up to decimetre-thick units at this location from pulsatory, quasi-continuous density currents consistent with earlier proposals of exceptional preservation through rapid burial; the density currents responsible were probably largely akin to mud-rich slurries, helping explain the transport and entombment of the fossils. The homogeneous mudstone units are characterized by numerous distinctive lenses of pyrite framboids or subeuhedral crystals, previously interpreted as small ripples. Their 3D shape, however, suggests an origin as subspherical early diagenetic aggregates; their present morphology is consistent with the high levels of compaction inferred from the preservation of fossils.
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 | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 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".