FURTHER STEPS

Each offset x_j allows us to make a different estimate of the earth model $\bold z_j$.There are two possiblities:

i.e. $\bold z_j \ne \bold z_{j+1}$.

$$\hat {\bold z}_j \quad =\quad\bold H_j' \bold L' \bold d_j$$ (3)

$$\hat {\overline{\bold z}}_j \quad =\quad\overline{\bold H}_j' \bold L' \bold d_j$$ (4)

We should plot $\hat{\bold z}_j$ as a function of j. We should also plot $\hat {\bold z}_j - \hat {\bold z}_{j-1}$as a function of j and see if we can find any higher temporal frequencies.