Geophysical characteristics of the southern Coromandel Volcanic Zone, New Zealand, and associated epithermal deposits
Bibliographic record
Abstract
SummaryGeophysical data from the southern Coromandel Volcanic Zone provide information critical to the investigation of epithermal mineral deposits and their regional structural setting. Regional gravity data show steep linear gradients that coincide with major faults bounding the Hauraki Rift to the west and the Waihi caldera to the east. Regional magnetic data are dominated by a large bi-polar anomaly coincident with the Waihi caldera, which may result from a sub-caldera intrusion, and otherwise by high-amplitude shorter wavelength magnetic anomalies associated with the volcanic rocks.High-resolution aeromagnetic and radiometric data reveal distinct signatures associated with epithermal deposits. Extensive magnetically quiet areas clearly delineate the location and extent of hydrothermal alteration zones around the deposits, whereas more localised zones of high K/Th ratios in these magnetically quiet areas delineate areas of intense potassium metasomatism. Epithermal deposits exhibit gravity signatures with two contrasting modalities: i) small negative anomalies (e.g. ≤30 gu at Golden Cross and Scotia) and ii) small positive anomalies (e.g. 40-50 gu at Karangahake and Waihi-Favona). Near-surface, low-density clay-altered andesite and/or enhanced fracture volume can account for small negative anomalies. However, positive gravity signatures show that significant mass anomalies must occur at greater depths; these may be either dense intrusions and/or zones of concentrated sulphide mineralisation.
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 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.002 |
| Science and technology studies | 0.000 | 0.001 |
| 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".