Chemical magnetization in Chinese loess

The relationship between the intensity of characteristic remanent magnetization (ChRM) and pedogenesis is examined in the Luochuan section. The results show a consistent link between the intensity values of remanent magnetization after every thermal demagnetization step and magnetic susceptiblity and other indexes of pedogenesis. Moreover, the intensity of ChRM is also much higher in paleosols than in loess. These results suggest that chemical remanent magnetization (CRM) is the main mode of NRM acquisition in paleosols and is linked to pedogenesis. Pedogenic processes overprint the magnetic signal to a certain depth in the underlying loess, so the interpretation of the high resolution paleomagnetic records from paleosols requires a degree of caution.

► Chemical remanent magnetization (CRM) linked to pedogenesis is the main NRM process in paleosols.
► Pedogenesis could confuse the interpretation of high-resolution paleomagnetic results.
► CRM may lead to a large lock-in depth in Chinese loess sequences.