ULF/ELF Atmospheric Radiation in Possible Association to the 2011 Tohoku Earthquake as Observed in China
Bibliographic record
Abstract
Recordings of a search-coil magnetometer located in Yongsheng in the Yunnan province of China have been used to find atmospheric ULF/ELF precursors to the 2011 Tohoku earthquake (EQ) with M=9 which occurred on 11 March 2011 with a large epicentral distance of about 4100 km. The combined characteristics of the horizontal magnetic fields, the ratio of tangential and radial field components in the numerator and root mean square of ellipticity in the denominator, were used to detect seismo-related ULF/ELF signals. This value is found to increase before the EQ, and then to decrease during a few weeks, with a reliable maximum on 8 March (3 days before the EQ). We also analyzed azimuth distributions of pulsed radiation in the frequency range 2-5 Hz during the previous week before the main shock. This radiation reached a maximal value on 10 March - one day before the EQ date, and the azimuth of its source is estimated to coincide with the position of the main shock. The results are further compared with the ULF/ELF precursors of the same EQ observed at 3 stations in Japan by Ohta et al. (2013).
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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 | 0.000 | 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 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".