Bibliographic record
Abstract
Two-dimensional arrays of three-component magnetometers have introduced a new geophysical technique useful in the study of the upper mantle and crust, particularly in tectonically active regions. Sources of incident magnetic fields include geomagnetic substorms and the daily variation. Methods and difficulties in interpretation are discussed in the light of the first five years' use of magnetometer arrays. Maps of Fourier transform coefficients assist qualitative interpretation but differ from other geophysical anomaly maps in combining the source field and the response of the Earth. For quantitative interpretation the normal (source) and anomalous (response) fields must be separated. Methods of separation and their limitations are considered. Numerical modelling of structures to fit normalized anomalous fields for two-dimensional geometries of conductors and fields is successful in some cases. In others, although the variation field anomaly and the current system are long and narrow, the behaviour is not two-dimensional because the regions of induction are distant and/or of unknown shape. Such ‘current concentration’ anomalies are common in the crust and can give rise to very large anomalies. In cases where the conductive geometry is complicated and not even crudely two-dimensional, Fourier transform anomaly maps are not very useful as their features are extremely variable, probably because of interference of the anomalous fields. In such cases transfer functions may prove helpful. Development of three-dimensional numerical modelling has started but is cost-limited at the present stage.
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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 | 0.002 | 0.018 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.002 | 0.002 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.003 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.003 | 0.001 |
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".