E4D User Guide

Travel-time Methods Simulated Data File

If specified in the output options file, E4D will produce a simulated data file, which provides a comparison of the observed and simulated data for a velocity distribution.

Variable Name Description
n_meas

(int)

 n_meas is the number of measurements.
m_ind  a     b     v_obs   v_sim

(int)     (int) (int) (real)    (real)

repeat repeat for n_meas


m_ind is the measurement number.

a is the sensor index of the source sensor.

b is the sensor index of the receiver sensor.

v_obs is the observed travel-time.

v_sim is the simulated travel-time.
TT Forward Model Example 

64  number of measurements
1 1 9  10 15.8351     m_ind a b m n v_obs v_sim
2 1 10 10 16.5005     v_obs is a placeholder value entered in the survey file,
...                   v_sim is simulated travel-time
TT Inversion Output Example 

64  number of measurements
1 1  9 15.9520 15.8351     m_ind a b m n v_obs v_sim
2 1 10 16.5160 16.5005     v_obs is observed travel-time (e.g. field data),
...                        v_sim is simulated travel-time from an inverse velocity model