Characteristics and Origin of Rare Earth Elements of Vermicular Red Earth in Middle Sub-Tropic Zone
Bibliographic record
Abstract
The vermicular red earth is a kind of sediment which is widespread in middle sub-tropic zone.It is similar to the loess in grain size,mineral composition of clay,sedimentary texture and so on.This study compared the rare earth element(REE) feature of the vermicular red earth in southern China with that of the loess and other Aeolian deposits in northern China,in order to understand the origin of vermicular red earth better.The REE contents of the samples were measured by using the ICP-MS.And 130 samples which were collected from Jiujiang,Xinzi and Shahe in Jiangxi Province,Jinhua and Anji in Zhejiang Province,Zhuzhou in Hunan Province were analyzed.The results suggest that the vermicular red earth is similar to dust deposits in REE features.Vermicular red earth also originates from well-mixed and multi-cyclic sediments.(1) The average REE content of vermicular red earth is 179.57μg/g,greater than that soils of China,but it is near to those of earths crust(178 μg/g),the dust storm deposit of Beijing suburb in Dec.1998(177.97μg/g) and Chinese standard loess samples(CJ-1 and CJ-2,average in 178.22μg/g).(2) The vermicular red earth show a similar REE distribution pattern as that of the dust deposits in northern China.The curve is sharp from La to Eu,and flat from Eu to Lu.The Eu shows negative anomaly.(3) The LREE content of vermicular red clay is dominant,but the average content of HREE is 14.26mg/kg(the percentage is less than 10%),obviously lower than the loess(18.89mg/kg) and Pliocene red clay(18.57 mg/kg) in the northern China.The ratios of LEE and HREE range from 9.86 to 15.15,which is higher than those of the loess and Pliocene red clay.The element Ce appears highly positive anomaly.(4) The calculation of provenance index(P_i) indicates that vermicular red earth is similar to the loess and Pliocene red clay in the northern China in chemical component.(5) Compared with the white parts,the red matrix of vermicular red earth is characterized by the low concentration and low ratio of REE,but the distributing pattern is identical. In a summary,all of the above evidences from REE suggest that the vermicular red clay in studied areas may originate from dust and have the same source as the aeolian deposits in the northern China.The dust has suffered stronger weathering than loess during the accumulating process.
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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) | 0.002 | 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 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".