Volcanic Glass in Soils of the Columbia Plateau, Pacific Northwest, USA
Bibliographic record
Abstract
Eolian soils on the Columbia Plateau are downwind of volcanoes of the Cascade Range, but content of volcanic glass has not been known. Because of the need for information on soil properties that affect wind erosion, we collected 174 surface samples (0–15 cm) of Columbia Plateau soils. We wanted to assess the influence of glass on these soils, to determine the source of glass, and to develop an interpretive model for the observed regional pattern of glass. We sonicated samples while wet sieving them to quantitatively separate 20‐ to 53‐ and 53‐ to 106‐mm fractions and point counted glass using a polarizing microscope. Content of glass in the 20‐ to 53‐μm fraction averages 5.9% in samples from the southwestern plateau and increases to average 27.5% in the northeastern plateau. A kriged map of glass content confirmed the pattern of increasing glass content to the northeast, away from volcanoes of the Cascade Range. Microprobe analysis confirmed that glass in the samples is from eruptions both of Mount St. Helens (1980) and Mount Mazama (6850 before present [BP]). The spatial pattern of glass content, however, did not correspond with the fallout pattern from the 1980 eruption. The spatial pattern resulted instead from bioturbation of a relatively uniform quantity of 6850 yr BP Mazama tephra into a northeastern‐thinning sheet of post‐6850 BP loess. Soil erodibility is highest in Columbia Plateau soils with very low glass contents and is lowest in soils with high glass content, so it would be premature to attribute high wind‐erosion susceptibility of these soils to volcanic glass content alone. The average content of glass in surface samples is 12.1%, thus the soils may be termed ash influenced or volcanic influenced but are not volcanic per se.
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 | 0.002 |
| Science and technology studies | 0.000 | 0.002 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 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 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".