Bibliographic record
Abstract
As re-interpreted in this paper, the Pliocene Footprint Tuff in Tanzania records a series of rapidly deposited air falls of crystal-vitric melilite nephelinite ash, rather than carbonatite as previously held. Footprints made by insects, birds, hominim and other mammals occur on ten bedding surfaces. Preservation of tracks in a succession of thin layers, totaling only 15 cm thick, required rapid cementation of each air-fall layer before the next was deposited. Calcite cement fills the interstices between pellets of altered glass and crystal fragments. The earliest calcite cement is botryoidal microcrystalline, and is relatively enriched in Fe, Sr, and Ba. Precipitation of microcrystalline calcite cement was sufficient to preserve the footprints. This early calcite predates the formation of root traces or burrows and through-going fractures that, in turn, predate the growth of the phillipsite cement. The final stage of cementation by sparry calcite predates the substantial alteration of the ash particles to clay. The sequence of diagenetic events in the ash points to an early history characterized by largely water-saturated conditions, followed by drying and shrinking of clays. There is no clear evidence for the involvement of carbonatite ash in the Footprint Tuff.
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 | 0.001 | 0.000 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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".