secular variation meaning in English

长年变化
长期变化
长期地磁变化
长期而缓慢的变动
长期缓慢变化
多年变化
经年变化
时效变化
世纪变化

Some features in the secular variation of the geomagnetic field in chinese mainland
中国大陆地磁场长期变化的某些特征
The basic characteristics of secular variation of geomagnetic field of sheshan seismic station
佘山台地磁场长期变化基本特征
Three - dimensional distribution of geomagnetic energy in the earth ' s interior and its secular variations
地磁场能量在地球内部的三维分布及其长期变化
Preliminary study on the mechanism of the geomagnetic secular variations in beijing over the last 12000 years
近12000年以来北京地区地球磁场变化机理探讨
This paper introduces the formation of magnetic field , polarity reversal , secular variation and the use of geomagnetic polarity reversal or susceptibility in stratigraphic study
摘要本文介绍了地球磁场的成因、极性变化以及运用极性倒转划分对比地层和指示环境。