Baseline Correction

Baseline correction is a procedure to correct certain types of long period disturbances on accelerometric signals

The simplest procedure is to subtract from the accelerogram its average value (which theoretically should be zero to ensure a zero velocity at the end of the seismic motion).

Alternatively, in the case of digital accelerograms with pre-event, it is possible to remove from the entire signal the average value calculated only on the pre-event portion.

Finally, in the case of more complex instrumental disturbances, more sophisticated baseline correction procedures can be used, for instance by first sub-dividing the velocity signal (obtained by integrating the initial accelerogram) into multiple ranges, by estimating subsequently the drifts relative to each range using least square regression, and finally by removing them.

In processing the accelerometric data contained in ITACA, the standard correction procedure has been used, i.e. the subtraction from the accelerogram of its average value.

For further details about the adopted correction procedure see Corrected Record.