A precursor to the Matuyama-Brunhes reversal in Chinese loess and its palaeomagnetic and stratigraphic significance
|Author(s)||Jin Chunsheng1, Liu Qingsong1, Cruz Larrasoana Juan2|
|Affiliation(s)||1 : Chinese Acad Sci, State Key Lab Lithospher Evolut, Inst Geol & Geophys, Beijing 100029, Peoples R China.
2 : Inst Geol & Minero Espana, Unidad Zaragoza, Zaragoza 50006, Spain.
|Source||Geophysical Journal International (0956-540X) (Oxford Univ Press), 2012-08 , Vol. 190 , N. 2 , P. 829-842|
|WOS© Times Cited||16|
|Keyword(s)||Magnetic fabrics and anisotropy, Palaeointensity, Reversals: process, timescale, magnetostratigraphy, Rock and mineral magnetism|
We report high-resolution palaeomagnetic results across the lower part of S8 in the Luochuan area, northwest of China using parallel subsets samples. A palaeomagnetic anomaly with low palaeointensity and disordered magnetic direction was identified similar to 21 ka prior to the MatuyamaBrunhes (MB) polarity reversal, and is consistent with the MB precursor observed from marine sediments and lava flows. This is the first convincing report of the MB precursor in terrestrial material (Chinese loess), which attests the global feature of the MB precursor. Constrained by the stratigraphic position of both the MB polarity reversal and the MB precursor, the loess unit L8 and palaeosol unit S8 of the Chinese loess sequence are undoubtedly tied to the marine isotope stages 18 and 19, respectively. This correlation is critical for an accurate understanding of the correspondences of palaeomagnetic records between the Chinese loess and marine sediments.