The cosmogenic radionuclide ¹⁰Be is produced by cosmic-ray spallation in Earth's atmosphere. Its production rate there is regulated by the geomagnetic field intensity (e.g., Frank et al. 1997;Muscheler et al. 2005), so that its accumulated concentration in aeolian sediments can in principal be used to derive high resolution records of geomagnetic field changes. However, there is few geomagnetic excursion studies from the Chinese loess-paleosol ¹⁰Be record reported before due to complexities arising from climate overprinting and recycled dust incorporation, which results in the fact that loess-paleosol ¹⁰Be was commonly used as a climatic proxy (Shen et al. 1992;Beer et al.1993;Heller et al.1993;Gu et al.1996). Therefore, efforts to extract weak geomagnetic excursion signals from Chinese loess-paleosol ¹⁰Be have generally been unsuccessful. Here, we present a reconstruction of geomagnetic relative paleointensities for the past 130 kyr from ¹⁰Be records in 2 Chinese loess-paleosol sections using a correction based on the correlation of ¹⁰Be with magnetic susceptibility (SUS) to remove the climatic contamination(Zhou et al. 2007). Both these records reveal the Laschamp and Blake events, which lie in the loess and paleosol (L₁SS₁ and S₁SS₃) horizons corresponding to mid-MIS 3 and 5e, respectively. The good agreement between our results and other geomagnetic intensities reconstructions from Atlantic and Pacific sediments indicates that our method is robust. Our study suggests the potential application of loess-paleosol ¹⁰Be for reconstructing geomagnetic intensity variations spanning the whole Quaternary.
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