Quaternary Tectonic Deformation, Holocene Paleoseismicity, and Modern Strain in the Unusually–Wide Coupled Zone of the Central Cascadia Margin, Washington and Oregon, USA, and British Columbia, Canada
Bibliographic record
Abstract
Vertical deformation and horizontal strains are analyzed in the central Cascadia margin, or the Juan de Fuca plate segment of the Cascadia subduction, zone to establish the widths of the inter–plate strongly–coupled zone and the transition zone. Local variability of marine terrace elevations, corresponding to marine isotope stages 5a–5e (~80-130 ka), in the south and central Oregon coast (32±23 m–to–10.5±7.4 m mean sea level) and in the northern Oregon and Washington coasts (9.5±3.2 m–to–7.6±2.1 m), constrain the width of the strongly coupled zone (~100 km) from the deformation front or buried trench along the central Cascadia margin in Washington and Oregon. Late Holocene tidal marsh sites (number = 25) in Washington demonstrate three conditions of cyclic coseismic subsidence, representing the first and second zero-isobases (< 0.5 m sea level rise) and the trough of maximum coseismic subsidence (1.0±0.5 m or > 1.5 m abrupt sea level rise) for most rupture events during the last 2.6 ka. Together with paleosubsidence data from the Oregon coast the tidal wetland records in Washington show that the first and second zero–isobases, respectively, reach distances of ~100 and ~200 km from the deformation front in the central Cascadia subduction zone. Global positioning system (GPS) baselines show that across–margin crustal shortening (strain rate -5 × 10-8 to -1.5 × 10-6 a-1) is about one order of magnitude larger than along–margin shortening (strain rate -2 × 10-8 to -5 × 10-7 a-1) near the coast during the last several years. Significant negative strain or shortening in the upper–plate is measured to 200 km distance from the deformation front, thereby establishing an unusually wide coupled zone (~200 km) in the central Cascadia margin. The landward limits of the west coupled zone, central uncoupled zone, and east coupled zone, respectively, could account for long–term uplift of the Coast Ranges, the lack of uplift in the Puget and Willamette forearc valleys, and uplift of the western margin of the Cascade volcanic arc.
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 distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| 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 teacher head, 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".