Central sagging of a giant mafic intrusion: the Ediacaran Sept Îles Layered Intrusion (Québec, Canada)
Bibliographic record
Abstract
Anisotropy of magnetic susceptibility data validated by image analysis were acquired on the Sept Îles Layered Intrusion. Most data come from the mafic Layered Series of the intrusion, although the overlying anorthositic Upper Border Series and felsic Upper Series were also investigated. In the Layered Series, Type 1 magnetic fabric defined by gently to moderately dipping foliations and horizontal to moderately plunging lineations dominates over Type 2 fabric characterized by steeply dipping magnetic foliations and lineations of variable plunge, although steep on average. The inverse relationship holds true for the Upper Border Series and only Type 1 fabric occurs in the Upper Series. Several observations, mainly centripetal disposition of the igneous layering, and inclination of the mean Type 1 foliation and lineation towards the deepest point of the intrusion, near its centre, demonstrate post-cumulus, central sagging of the Layered Series. The Type 2 fabric recorded the effect of synmagmatic discontinuities, possibly shear zones, in the Layered Series, its origin being speculative in the Upper Border Series. The mean Type 1 lineations of the Layered Series and the Upper Series are discordant, suggesting that the latter was slightly affected by the sagging of the underlying cumulates, possibly owing to its rapid waning. Supplementary material: Analytical methods (Appendix 1) and equal-area projections of the anisotropy of magnetic susceptibility principal axes (Appendix 2) are available at https://doi.org/10.6084/m9.figshare.c.5057499.v1
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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 | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.004 | 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".