Deducing mineralogy of serpentinized and carbonated ultramafic rocks using physical properties with implications for carbon sequestration and subduction zone dynamics
Bibliographic record
Abstract
Serpentinization of ultramafic rocks is fundamental to modern plate tectonics and for volatile (re-)cycling into the mantle and magmatic arcs. Serpentinites are also highly reactive with CO 2 such that they are prime targets for carbon sequestration. Serpentinization and carbonation of ultramafic rocks results in changes in their physical properties such that they should be detectable using geophysical surveys; this could provide constraint on the reactivity of rocks without extensive sample characterization. We constrain the physio-chemical relationships in altered ophiolitic ultramafic rocks using petrographic observations, major-element chemistry, quantitative X-ray diffraction, and physical properties on a suite of >400 samples from the Canadian Cordillera. Serpentinization results in a systematic decrease in density that reflects the increase in serpentine abundance and carbonation results in an increase in density, mostly reflecting the formation of magnesite; based on these data we present two formulations for determining extent of serpentinization: one based on major-element chemistry and the other on density. Magnetic susceptibility is variable during serpentinization; most harzburgitic samples show a 100-fold increase in magnetic susceptibility, whereas most dunitic samples and a minor proportion of harzburgitic samples show very little change in magnetic susceptibility. We use quantitative mineralogy and physical properties of the samples to constrain a model for using density and magnetic susceptibility to approximate the mineralogy of ultramafics rock. Although further work is required to understand the role of remanence in applying these models to geophysical data, this presents an advancement and opportunity to prospect for the most reactive ultramafic rocks for carbon sequestration.
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 | 0.000 | 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".