Abstract: The mathematical expression of the original horizontal plane can be obtained by coordinate transformation,provided that the following conditions are fulfilled:1. The block where the volcanic rocks outcroped has not been displaced in north-south direction; 2. The statistical average vector of the remanent magnetization follows the axial geocentric dipole magnetic field. In that case,it will enable us to get more reliable amounts of the rotation of the block around the vertical axis,and that of the tilting of the strata around the horizontal axis,based on paleomagnetic method. In addition,it will be possible to apply paleomagnetic method to the study of the tectonic movement of volcanic rocks with ambiguos attitute.

Key words: Cenozoic volcanic rocks, Paleomagnetism, Primary remanent magnetization, Neotectonics

摘要： 新生代火山岩生成以来,如果所在地块没有发生过明显地南北向位移,并且火山岩原生剩磁矢量的统计平均值满足轴向地心偶极子磁场规律,那么通过座标转换可以得到其生成时期原始水平面经构造变动后呈现今产状的数学表达式。从而使用古地磁方法确定的块体绕垂直轴的旋转量和地层绕水平轴的掀斜量更为接近客观实际。同时也使无产状可寻的新生代火山岩用古地磁方法研究其构造运动成为可能。

关键词: 新生代火山岩, 古地磁, 原生剩磁, 新构造