The ups and downs of the Canadian Shield: 1- preliminary results of apatite fission track analysis from Hudson Bay region
Bibliographic record
Abstract
The low-temperature (120-60°C) thermal history of seven samples from the Hudson Bay region has been investigated using apatite fission-track (AFT) analysis. Apatite grains from six Precambrian rock samples from the surface or the bottom of hydrocarbon-targeted wells and from one sample belonging to a thin Upper Ordovician sandstone unit at the base of the Paleozoic succession were analysed. All apatite fissiontrack (AFT) ages are younger than the age of their host rocks indicating that fission tracks experienced significant post-crystallisation or deposition annealing and samples were subjected to temperatures > 60°C. The track length distributions suggest slow cooling. AFT pooled ages range from 215.1 ± 15.0 to 462.7 ± 29.9 Ma. The sample from Akpatok Island, in Hudson Strait has the youngest AFT age, suggesting that the exhumation history of this area may be different from the Hudson Bay Basin. Inverse modeling of AFT data provides an estimate of the maximum temperature experienced during the Paleozoic burial episode and, with much less accuracy, the timing of maximum heating. For the two wells that have both organic matter maturation and AFT data, the measured vitrinite equivalent value is higher than that calculated reflectance using AFT inverse modeling results. AFT results from the Hudson Bay region are broadly in agreement with those reported for the southern Canadian Shield. However, the available dataset is not sufficient to depict regional variations of maximum heating conditions, an issue that is critical for the hydrocarbon assessment of the area.
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 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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".