Radioactive elements in collisional and within-plate Sodic-Potassic Granitoids: Accumulation levels and metallogenic significance
Bibliographic record
Abstract
New data are reported on the content of radioactive elements in the Precambrian Na-K granitoids from the southwestern margin of the Siberian Craton, Aldan and Ukrainian shields, and Kursk-Voronezh Massif. Analytical data on other regions were generalized for comparison. Two global epochs of Na-K granitoid magmatism bearing elevated contents of radioactive elements (U, Th, K) were distinguished in the Early Precambrian (in Ga): Neoarchean (2.8-2.6) and Late Paleoproterozoic (1.9-1.75). Mesoarchean (3.1-2.8 Ga) epoch of Na-K granite formation has been additionally distinguished at the Australian, South African, and Canadian shields. These epochs of granitization provided high maturity of the crust: geochemical differentiation of the oldest continental blocks and their geochemical and metallogenic specialization for trace elements and RAE. In the southern margin of the Siberian Craton, the most intense granite formation occurred in the Late Paleoproterozoic. The extended South Siberian belt of collisional and within-plate Na-K granitoids is characterized by intense influx of RAE and other trace elements in the upper crustal shell. The southwestern margin of the craton (Yenisei Range) was spanned by repeated Late Neoproterozoic Na-K granite formation, with wide development of collisional and within-plate Na-K granites having elevated Th content and [Th]/[U] ratio. The higher RAE concentrations are typical of within-plate Paleo and Neoproterozoic granitoids. The highest uranium content was found in the postcollisional and within-plate Na-K granites and subalkaline leucogranites. Uranium ore concentrations were formed at the riftogenic stages of evolution of these crustal blocks, when within-plate subalkaline acid magmatism and accompanying hydrothermal metamorphism overprinted granitized crystalline massifs, including high-U sedimentary and volcanic complexes. Areas with the most favorable geological-geochemical environments for the formation of uranium mineralization were distinguished in the southern margin of the Siberian Craton and its nearest folded framing.
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) | 0.003 | 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".