SHOCKED QUARTZ AS AN INDICATOR OF THE LOADING AND RELAXATION CONDITIONS DURING AND AFTER HYPERVELOCITY IMPACT - MICROSTRUCTURAL EVIDENCE FROM CRYSTALLINE TARGET ROCKS OF THE CHARLEVOIX IMPACT STRUCTURE, CANADA.
Bibliographic record
Abstract
The loading and relaxation conditions (e.g., pulse duration, pressure, differential stress and temperature) during and after hypervelocity impact are dependent on the velocity, material and size of the projectile, as well as on the material properties of the target rocks, including macroscopic and microscopic structural features (e.g., foliation, grain size, etc.) and shock impedance variation between adjacent phases. The shock effects generated in the target rocks are sensitive to these conditions and can therefore provide important information on the cratering process. The late Devonian Charlevoix impact structure is located 105 km north of Quebec city (47°32’N; 70°18’W) along the north shore of the St. Lawrence River. The topographic expression of the ~55 km diameter complex structure with a prominent central peak is well defined. Shocked quartz from the crystalline target rocks has been studied by optical microscopy, U-stage and scanning electron microscopy, combined with electron backscattered diffraction (EBSD). The shocked quartz crystals reveal planar fractures (PFs) and planar deformation features (PDFs) (Fig. 1).
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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 | 0.000 |
| 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".