Synthesis of the Seismic Structure of the Greater Alaska Region: Subducting Slab Geometry
Bibliographic record
Abstract
We utilized a normalized vote method to define common features in teleseismic, body-wave tomography models produced from the Alaska USArray data. The metric is used with three-dimensional visualizations to define subducting slab geometry. We observe the following features. (1) The eastern end of the slab downstream from the Yakutat microplate has a flap-like structure extending to 300–350 km depth that is bounded on the east by an edge consistent with rigid plate kinematics and on the west by a tear located downstream from the western limit of Yakutat rocks. (2) The geometry matches Slab2.0. (3) Below Slab2.0, the dip steepens to form a vertical structure that extends to the top of the mantle transition zone. Within the transition zone, the geometry changes from north to south dipping to form a lithospheric scale, recumbent fold connected to a lower-mantle structure located ∼1,000 km south of the trench. (4) A previously unknown mantle structure extends eastward from the flat slab to an edge predicted by rigid plate kinematics suggesting it is an older section of the Pacific Plate emplaced before the Yakutat tear initiated. We propose a new kinematic model of subduction history in Alaska since 40 Ma consistent with the new data.
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 | 0.001 |
| 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) | 0.003 | 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".