iloc ssst integration

Some background materials:

Summary ppt

Three-dimensional empirical traveltimes: construction and application

High-precision relocation of long-period events beneath the summit region of K¯ılauea Volcano, Hawai‘i, from 1986 to 2009

Revision of earthquake hypocentre locations in global bulletin data sets using source-specific station terms

Useful tutorial

Fortran code here may be useful.

Steps:

1. Use iloc on all events and record the residuals.
2. Calculate mean/median ssst for each grid and each station and interpolate the residuals for the whole country.
3. Use iloc for each event and go back to 1. Repeat this cycle a few times.
4. Optionally do a static station terms calculation (at which step?)

We are to either use a thin plate spline interpolation with generalized cross validation or 3D kriging to interpolate the travel time residuals.

Defn of Travel Time Residual: observed travel time - theoretical travel time.