Reconstructing the deglacial dynamics of the northwestern Laurentide Ice Sheet 
Bibliographic record
Abstract
The northwestern sector of the Laurentide Ice Sheet drained ice from the Cordilleran-Laurentide ice saddle and the Keewatin ice dome towards the ice margin on the arctic continental shelf during its late local Last Glacial Maximum. The glacial geomorphological and geological record of the region documents several massive palaeo-ice streams. However, the deglacial dynamics of this sector has not yet been reconstructed in detail and questions remain about the nature of deglaciation in this region: Did ice streams operate far up-ice or were they limited to a rather narrow ice-margin zone? Was ice stagnation widespread?We reconstruct the deglaciation of the northwestern sector of the Laurentide Ice Sheet by glacial geomorphological inversion methods, based on our recent regional-scale mapping of the glacial geomorphological record. We find that the ice stream network evolved from large, marine-terminating ice streams to shorter, terrestrial ice streams. The ice drainage network experienced a reorganisation following the disappearance of the Cordilleran-Laurentide ice saddle, which previously feed ice in a northerly direction along the modern-day Mackenzie River, to more westerly ice flow sourced from the Keewatin ice dome. Deglaciation was dominated by dynamic ice retreat but we also find traces of localized ice stagnation in areas of higher ground fringing the major fast ice flow corridors. The ice flow pattern changed markedly once the ice front stepped back onto the Canadian Shield, where ice streaming largely ceased. This empirical reconstruction, fitted to the latest version of ice margin chronology, can serve as validation for numerical modelling efforts and provides information on broad-scale ice sheet dynamics during the last deglaciation.
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 | 0.000 | 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) | 0.001 | 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".