Abstract
We used a partial heating/cooling method (Van Velzen and Dekkers, 1999) for the analysis of representative samples of the Holocene loess of the Chinese loess plateau, in order to investigate magnetic mineralogical changes during thermal treatment. The temperature-dependence of susceptibility (TDS) results show significant alteration of magnetic phases during heating and cooling, and provide further evidence that magnetite and maghemite are the dominant ferrimagnetic minerals in the Holocene eolian deposits of the loess plateau. The TDS measurements suggest that the degree of the thermally-induced alteration is closely related to pedogenesis, which is a function of climate, and thus the alteration itself could be a useful climate indicator. Our TDS results along a NW-SE transect in the loess plateau suggest that stronger pedogenesis results in higher content of maghemite and greater susceptibility decrease during thermal treatment. This behavior seems to indicate that the final product of pedogenic magnetite in Chinese loess and paleosols is maghemite, which plays an important role in the enhancement of the magnetic susceptibility of Chinese eolian deposits.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 873-878 |
| Number of pages | 6 |
| Journal | Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy |
| Volume | 26 |
| Issue number | 11-12 |
| DOIs | |
| State | Published - 2001 |
Bibliographical note
Funding Information:Acknowledgements. The authors gratefully acknowledge critical reviews by Dr. Mark J. Dekkers and an anonymous reviewer. C. Deng thanks Dr. Yuan Baoyin for field assistance. This research is supported by the National Natural Science Foundation of China (Grant Nos. 40074016a nd 49425405)a nd the National Science Foundation of USA (Grant No. EAR-9710051).