Palaeointensity determinations, palaeodirections and magnetic properties of basalts from the Emperor seamounts
Bibliographic record
Abstract
We measured palaeodirections and palaeointensities by the Thellier method on 93 samples from three of the Emperor seamounts: 20 from Detroit seamount (81 Ma), 48 from Nintoku seamount (56 Ma) and 25 from Koko seamount (48 Ma).Reliable palaeodirections obtained from three lava flows on Nintoku seamount give an average palaeolatitude of 32.7 • , which is different from the present-day latitude of Hawaii and supports the hypothesis of a moving hotspot.According to the selection criteria traditionally used in palaeointensity determination, 17 samples give a reliable result.The samples show a very wide variety in unblocking temperatures, revealing an important variation in titanium content and the oxidation state of titanomagnetites.In order to assess the reliability of the palaeofield recording in the accepted samples, we carried out measurements of saturation isothermal remanent magnetization at low temperature and thermomagnetic curves.We found Curie temperatures varying from 250 to 580 • C, not only between seamounts but even within one lava flow.Thermomagnetic curves enabled us to identify titanomaghemite in several lava flows.After rejecting the results from samples showing evidence of maghemitization, only four samples, all from Nintoku seamount, can be considered as truly reliable.The palaeointensity values range between 34.2 and 36.9 µT.The low virtual axial dipole moment (VADM) values calculated from the palaeofield values are consistent with the most reliable VADM estimates in this time range and they are very close to the average VADM in the 0.3-300 Ma time interval.
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 | 0.000 |
| 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 | 0.000 | 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".