Seismic delineation of the Orion South kimberlite, Fort à la Corne, Canada
Bibliographic record
Abstract
ABSTRACT The Orion South (140/141) kimberlite is a diamondiferous, multiphase volcano-sedimentary complex within the Cretaceous Fort à la Corne kimberlite field of Saskatchewan, Canada. A network of seven high-resolution 2D seismic reflection profiles were acquired to test the utility of using seismic methods in defining the subsurface architecture of the kimberlite complex, and to provide auxiliary constraints on interborehole geologic correlations. The seismic data were interpreted in conjunction with a set of drillhole geologic logs and associated geologic sections and models, and physical rock properties from core measurements and geophysical logs. Core-determined average density values for the kimberlite suite are low (2240±16 kg/m3), but with some kimberlite facies having significantly higher values (2330 to 2540 kg/m3). Sonic velocities for the kimberlites are 2500−3500 m/s as compared with ∼2000 m/s and 3800−4500 m/s for the enveloping shale and sandstone units, respectively. The kimberlite is imaged to depths of ∼400 m as a lenticular-shaped body lying beneath, Quaternary glacial till and a mantle of Cretaceous marine sediments. The base of the kimberlite is variably imaged due to faulting and lateral changes in the seismic contrast with the underlying Cantuar sandstone. The comparable magnitude of seismic contrasts across inter- and intraeruptive phase boundaries hampers interpretation of the individual eruptive phases within the kimberlite complex, although the conformal nature of internal reflections with the interphase boundaries is useful in mapping these boundaries away from the drillholes. Multiple feeder vents at the base of the complex and their associated vertical faults are clearly identified by truncations of subhorizontal reflectivity. This study demonstrated how a network of relatively low-cost seismic profiles could potentially be useful in guiding detailed delineation drilling of kimberlite deposits.
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 | 0.002 | 0.002 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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".