Magnetostratigraphy of the Qiliting section (SE China) and its implication for geochronology of the red soil sequences in southern China

The red soil sequences in southern and southeastern China provide important terrestrial archives of palaeoclimate and palaeoenvironment and are important sources of Palaeolithic settlements and, therefore, early human occupation. Here we present detailed palaeomagnetic investigation coupled with mineral magnetic and petrographic analyses of a red soil sequence at Qiliting, southeastern China. The sediments contain both strongly magnetic minerals (such as maghemite and magnetite) and weakly magnetic minerals (such as haematite and possibly goethite). Maghemite and haematite were identified as the main carriers of the natural remnant magnetisations. Only haematite dominates the characteristic remnant magnetisations. Palaeomagnetic findings suggest that the Qiliting sedimentary sequence recorded the early Brunhes Chron and the late Matuyama Chron, including the Jaramillo Subchron. Our finding, coupled with previously published magnetostratigraphy, establishes that the red soil sequences in southern China began to accumulate no later than the Jaramillo age (i.e. similar to 1.0 Ma). It is further suggested that the capabilities of recording magnetic polarity stratigraphy in Chinese red soil sequences are variable between areas because of different climate regimes.