Why are paleoseismological data useful in forecasting earthquakes?

The answer is: Because with it, evidence is sought in the faults in order to establish the repetition period that the earthquakes have.

Explanation:

Paleoseismology: evidence is sought in faults, such as the displacements of some geomorphological or geological element. On the ground, it starts perpendicularly and the displacements caused by the fault at a few meters deep are observed and measured, all to establish the period of recurrence of earthquakes, dating with carbon 14. If it is centimetric displacement, there are empirical relationships to know more or less a range of magnitude.

The answer is: Because with it, evidence is sought in the faults in order to establish the repetition period that the earthquakes have.