異常地殻変動検出手法の開発

Abstract

我々は異常地殻変動検出手法の開発に取り組んでいる。時定数の短い変動を捉えるためには，キネマティック測位を応用した手法を用いて，電離層や対流圏遅延などの誤差要因を除去しなければならない。これらを移動平均によって±1cmの精度まで取り除くことができた。さらに長基線に展開するため，新たに空間フィルター法を適用し共通誤差成分を取り除くことによって，基線の長さに関係なく±1cmの精度で議論できるようになった。また衛星軌道暦の違いによる測位精度への影響はほとんどないので，準リアルタイムモニタリングシステムの構築が可能になった。

We are taking with the development of the technique which detects the anomalous crustal deformation by using GPS now. The static positioning method which used a daily solution was the main stream with the positioning which used GPS till now. However, the short-term change can’t be caught in this method. So, we think that the kinematic GPS positioning method being used for the moving object was applied. But, we must remove various error factors which exist in this technique. As for the short baseline which went until last year, we could remove the influences of the ionospheric and tropospheric delay, and the positioning accuracy is +/- 1 cm. We extend a baseline more this year. We succeed in removing the error factors from the sky by using a spatial filter, and we can get the same result as the short baseline. And we must remove the error to result from the satellite orbit to monitor it in real time. As that result, a large difference wasn’t seen in the positioning accuracy which satellite orbit announced from IGS was used.