Palynofacies analysis of surface sediments from the Beagle Channel and its application as modern analogues for Holocene records of Tierra del Fuego, Argentina
Bibliographic record
Abstract
Palynofacies analysis of surface sediments from the Beagle Channel, Tierra del Fuego, Argentina, was carried out to establish modern analogues for comparison with other Holocene marine records in southern Isla Grande de Tierra del Fuego. Our results show the dominance of highly degraded translucent phytoclasts, associated with amorphous organic matter (AOM) and palynomorphs, while opaque phytoclasts are poorly represented. The organic constituents indicate the proximity of the continental source area to marine environments, with distances and/or times of relatively short transport. The predominance of translucent phytoclasts associated with pyrite suggests reducing conditions, probably associated with marginal-marine environments. Among the terrestrial palynomorph group, the predominance of Nothofagus pollen reveals the presence of forests along the channel. The high terrestrial organic matter input to the depositional area are consistent with a marginal-marine environment. The aquatic palynomorphs, mainly dinoflagellate cyst's show assemblages characterised by low species diversity and low concentration values. The dominance of Peridiniales over Gonyaulacales suggests inner neritic environments. Comparison with two fossil sections of Mid–Late Holocene age (Albufera Lanushuaia and Río Ovando) shows similar distribution of the total palynological matter.
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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 | 0.003 | 0.002 |
| Science and technology studies | 0.000 | 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".