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对黄土高原定边、西峰、渭南三个剖面中古土壤层S1的定向连续古地磁样品作了详细的岩石磁学和古地磁学研究，均未发现Blake极性事件．在对其成因进行了分析研究后，提出如下看法：（1）六盘山以东黄土高原北部边缘的风成沉积可能存在局部的不连续性，因而没有记录Blake极性事件；（2）黄土沉积物的主要载磁矿物力磁铁矿，次生磁性矿物对剩磁的贡献可能大于原生磁铁矿，故在六盘山以东黄土高原北部边缘没有发现Blake极性事件；（3）六盘山以东黄土高原中部和南部地区，强烈的成土作用掩盖了持续时间较短的Blake极性事件；（4）六盘山以西的黄土高原具高速稳定沉积的特点，且成土作用弱，可记录Blake极性事件．
Detailed rock magnetism and paleomagnetism studies were conducted on the directional continuous paleomagnetic samples of S1 in the middle soil layer of the Dingbian, Xifeng and Weinan sections of the Loess Plateau. No Blake polarity event was found. After analyzing and analyzing its causes, the following opinions are put forward: (1) There may be some local discontinuities in the aeolian deposits on the northern margin of the Loess Plateau to the east of the Liupan Mountains, and thus no record of Blake polar events; (2) The main magnetite loaded magnetite and secondary magnetic minerals may contribute more to the residual magnetism than the primary magnetite. Therefore, no Blake polarity event is found on the northern edge of the Loess Plateau to the east of Liupan Mountain. (3) In the central and southern parts of the eastern Loess Plateau, strong soil-forming action obscures the short-duration Blake polarity event. (4) The Loess Plateau west of Liupan Mountain is characterized by high-speed and stable deposition and weak soil-forming ability. Blake Polar events.