南海某工区多站地磁日变改正值推算

Multi-observatories calculation of diurnal correction for marine magnetic data of certain area in the South China Sea

日变改正是海洋磁测数据预处理比较重要的一个步骤,改正效果对处理后数据精度影响较大。受台站距离工区较远等因素影响,单一台站日变数据改正效果欠佳。选取存在此类问题的南海某工区实测磁力数据,引进纬差加权法,由多台站数据推算工区内某纬度处日变数据,并根据改正后交点差分布,分区块使用不同台站数据进行改正,结果发现,在一定程度上改善了日变改正效果,处理后的数据精度有所提升。

Diurnal correction is an important step in marine magnetic data process.The effect of diurnalcorrection influences data precision seriously.Correction result of single geomagnetic observatoryis not ideal because of several factors such that the observatory is far away from research area.We import the multi-observatories calculation method for the actual measurement of an area inthe South China Sea,where suffer this problem,and use different geomagnetic data in differentblocks according to the distribution of cross difference.Then,the results that we obtain are higherprecision than before.