E4D User Guide

Electrical 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 conductivity distribution.

Variable Name Description
n_meas

(int)

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

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

repeat repeat for n_meas


m_ind is the measurement number.

a is the electrode index of the positive current electrode.

b is the electrode index of the negative current electrode.

m is the electrode index of the positive potential electrode.

n is the electrode index of the negative potential electrode.

v_obs is the observed transfer resistance.

v_sim is the simulated transfer resistance.
ERT Forward Model Example 

2070  number of measurements
1 1 2 3 4 10 -25.2777     m_ind a b m n v_obs v_sim
2 1 2 4 5 10 -6.51073     v_obs is a placeholder value entered in the survey file,
...                       v_sim is simulated resistance
ERT Inversion Output Example 

2070  number of measurements
1 1 2 3 4 -26.5258 -25.2777     m_ind a b m n v_obs v_sim
2 1 2 4 5 -6.63145 -6.51073     v_obs is observed resistance (e.g. field data),
...                             v_sim is simulated resistance from an inverse conductivity model
Variable Name Description
n_meas

(int)

 n_meas is the number of measurements.
m_ind  a     b     m    n     v_obs   v_sim   i_obs   i_std

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

repeat repeat for n_meas


m_ind is the measurement number.

a is the electrode index of the positive current electrode.

b is the electrode index of the negative current electrode.

m is the electrode index of the positive potential electrode.

n is the electrode index of the negative potential electrode.

v_obs is the complex observed transfer resistance.

v_sim is the complex simulated transfer resistance.

i_obs is the observed phase.

i_sim is the simulated phase.
SIP Forward Model Example 

2070  number of measurements
1 1 2 3 4 10.0 -17.8642 100.0 -0.996722E-01     m_ind a b m n v_obs v_sim i_obs i_sim
2 1 2 4 5 10.0 -3.87208 100.0 -0.996716E-01     v_obs and i_obs are placeholder values entered in the survey file,
1 1 2 5 6 10.0 -1.48055 100.0 -0.996488E-01     v_sim and i_sim are complex transfer resistance and phase, respectively
...