Long-period vertical seismogram on paper

Detailed Description
An example film chip scan of a long-period vertical seismogram recorded at the WWSSN station KEV (Kevo, Finland). The stamp on the bottom left gives the metadata for this film chip. A calibration pulse is seen at the beginning of the day and at the end. The earthquake recorded on this film chip is the 9 February 1971 M 6.5 San Fernando, California, earthquake.
Sources/Usage
Public Domain.
The Albuquerque Seismological Lab WWSSN Film Chip Preservation Project
A. C. B. Alejandro, C. R. Hutt, A. T. Ringler, S. V. Moore, R. E. Anthony, D. C. Wilson; The Albuquerque Seismological Lab WWSSN Film Chip Preservation Project. Seismological Research Letters ; 90 (1): 401–408. doi: https://doi.org/10.1785/0220180275