摘要
The authors have carried out a detailed rock magnetic investigation on the loess-paleosol sequences in the Jingyuan and Gulang sites, northwestern margin of Chinese Loess Plateau, including low-field magnetic susceptibility (χ), frequency-dependent susceptibility (χfd%), temperature-dependent susceptibility (χ-T), isothermal remanent magnetization (IRM) and hysteresis loop. The results demonstrate that the total amount of magnetic minerals in Jingyuan and Gulang loess-paleosol sequences is relatively low, and the main magnetic mineral in paleosol and loess is magnetite, where there are maghemite and hematite as well. It results from the fact that less fine-grained magnetite are generated in loess than in paleosol, for there are coarser magnetic particles transported from the source area of eolian to loess layer than to paleosol layer.