Final answer:
It would be surprising to detect frequent, violent earthquakes on Mercury using seismographs since the planet lacks plate tectonics. Mercury's geological activity is mostly from its past, evidenced by long scarps from crustal contraction, and not ongoing seismic activity.
Step-by-step explanation:
If we placed seismographs on the surface of Mercury and recorded frequent, violent earthquakes, it would indeed be a surprising finding. Mercury, unlike Earth, does not exhibit evidence of plate tectonics, which is one of the primary causes behind significant seismic activity on our planet. Mercury does have long scarps, suggesting some past geological activity such as the contraction of the planet's crust after it had cooled and solidified, yet most of this activity occurred after the formation of the craters and is likely not ongoing.
Seismic activity on Mercury could indicate ongoing geological processes that we do not currently understand or have not yet observed. In contrast to Mercury, Earth and Venus have experienced extensive geological activity. However, unlike Earth, Mercury’s smaller size and lack of atmospheric protection leave it more vulnerable to impacts from space, which could theoretically cause measurable seismic activity detectable by a seismograph.