Expanding the Operating Frequency Range of SM-3KV Short-Period Seismometers

The article provides an example of an instrumental solution for expanding the frequency band of the sensor into the low-frequency region using the SM-3KV short-period seismometer. The correction circuit is built on two stages of integrators on operational amplifiers. The developed prototype SM-3KV-cor was tested in laboratory and field conditions. Analysis of records of explosions and earthquakes showed that the developed scheme can be used when conducting seismic monitoring at frequencies above 0.06 Hz. When compared with data from a broadband seismometer, it is shown that the SM-3KV-cor can be used to reconstruct the velocity features of the Earth’s crust near the installation site of a seismic station based on the construction of receiver functions. When analyzing the total records of P-S converted waves, a phase was identified from the lower boundary of the phase transition zone of the upper mantle at a depth of about 660 km, which suggests the possibility of using the SM-3KV-cor sensor also to analyze the features of the phase transition zone.