A Time-Term Interpretation of the First-Arrival Data of the 1963 Lake Superior Experiment
Bibliographic record
Abstract
The first-arrival data of the Lake Superior Experiment of 1963 have been interpreted by the time-term method, which analysis has shown to be well suited to this type of survey, and the results appear to be consistent and meaningful. Approximately 500 first arrivals from head waves generated at the Mohorovičić discontinuity have been reduced to estimates of crustal time terms at more than 100 locations. A much shallower refracting surface, here called the upper refractor, furnished nearly 1000 observations to yield upper-crustal time terms at the same locations. The analysis reveals the material beneath the upper refractor and beneath the M discontinuity to have velocities of 6.63 and 8.10 km/sec, respectively. On the basis of a simple interpretation of the time terms, the surface of the upper refractor is revealed as undulating, coming close to the surface at the edges of the lake, and reaching maximum depths (not exceeding 15 km) to the east and west of the Keweenaw Peninsula. On a similar basis the M discontinuity is revealed as an easterly dipping surface, having a depth of approximately 35 km at the west end of the lake and reaching a maximum depth of about 60 km in the region just west of the Keweenaw Peninsula. Eastward, the time-term values fluctuate but do not increase or decrease systematically.
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 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 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.002 |
| 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) | 0.003 | 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".