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磁倾角是古纬度的记录者,对许多构造活动有着很好的揭示作用。但在青藏高原,沉积物的磁倾角往往要比火山岩或欧亚极预测的值要小,这很大程度上制约了对该地区构造演化历史的了解。本文应用E/I统计分析法对青藏高原东北部几个典型山间盆地的已有古地磁数据进行分析,发现该地区沉积物中普遍存在的10°～20°磁倾角浅化可以通过该法矫正,揭示出该地区的磁倾角浅化可能是由于沉积物在沉积过程中或沉积后的压实作用造成;同时也表明该地区在晚新生代以来南北向缩短量并不是十分显著,至少是在古地磁研究的误差范围以内。
Magnetic inclination is the record of ancient latitudes, for many tectonic activities have a good revelation. However, in the Qinghai-Tibet Plateau, the dip of sediments is often smaller than that predicted by volcanics or Eurasia, which largely restricts the understanding of the tectonic evolution history of the area. In this paper, the paleoeomagnetic data of several typical mountain basins in the northeastern Qinghai-Tibet Plateau are analyzed by E / I statistical analysis method. It is found that the shallow 10 ° ~ 20 ° magnetic dip in the sediments of this area can be obtained by this method Correcting and revealing that the shallow inclinations in this area may be caused by the compaction of the sediments during or after sedimentation; it is also indicated that the shortening of the north-south direction in this area is not very significant at least since the Late Cenozoic Within the error range of paleomagnetic research.