Structural complexity inferred from anisotropic resistivity: Example from airborne EM and compilation of historical resistivity/induced polarization data from the gold-rich Canadian Malartic district, Québec, Canada
Bibliographic record
Abstract
ABSTRACT Structurally complex zones within orogenic terranes typically correspond to areas where there is interference between multiple fold generations and are known to be favorable pathways for fluid flow because of their higher permeability. In the Canadian Malartic district, gold anomalies have been linked with zones of structural complexity that have been quantified by outcrop bedding orientation measurements and calculation of bedding variance maps. In this work, historical apparent resistivity and induced polarization data in the Canadian Malartic district were reprocessed and combined with new surveys to create a compilation of inverted chargeability and resistivity, which were then interpreted together with airborne electromagnetics and outcrop structural data. The results indicate chargeability anomalies, up to five times the background value, associated with the sulfide mineral content in monzodioritic dikes that are thickened in folds and hydrothermally altered. Although the airborne apparent half-space resistivity is mostly sensitive to conductive surficial cover, the inverted ground resistivity method is sensitive to deeper structure and likely represents bedrock signal at depths greater than 25 m. Inverted ground resistivity exhibits strong anisotropy in areas of subvertical bedding, where measured resistivities can vary by up to a factor of two, over the same location, depending on whether the survey lines are perpendicular or parallel to the strike of bedding. This result is observed at scales of 50 cm up to 100 m. Analysis of inverted ground resistivity together with bedding variance indicates a strong correlation between structurally complex zones with high bedding variance and a decrease in resistivity at depths greater than 25 m. This suggests that in places where the presence of disseminated gold cannot be directly detected, or where the outcrop exposure is limited due to overburden cover, geophysical data may still succeed in identifying structural complexity zones that could potentially host mineralization.
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 | 0.001 | 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".