A RECORD OF THE BLAKE EVENT DURING THE LAST INTERGLACIAL PALEOSOL IN THE WESTERN LOESS PLATEAU OF CHINA

A high-resolution record of the Blake Event has been obtained from a 4 0 m well dug in a loess section at Jiuzhoutai in the City of Lanzhou i n the western Loess Plateau of China. The paleomagnetic signal is prin cipally carried by magnetite both in loess and paleosols. The Blake Ev ent is located at the boundary between paleosol S1-c of the last inter glacial (equivalent to MIS 5e in deep-sea records) and loess L2-2 (MIS 5d), and is characterized by a triple feature consisting of two short reversed intervals separated by a short normal interval. The directio nal changes are abrupt, as previously revealed in other records, and s uggest geocentric dipole field behavior before, after and during the e vent, but not necessarily during N-R or R-N transitions. The age and d uration of the event are estimated as between 119.97 and 114.47 kyr BP and 5.5 kyr, respectively, from thermoluminescence dating and astrono mically tuned climate stratigraphy based on high-resolution magnetic s usceptibility.