Nuclear explosions can cause earthquakes and even a sequence of aftershocks, but the seismic activity generated by these explosions is much smaller than the explosion itself. The relative amplitude of the waves can also be an indicator of an explosion and not of a natural earthquake. In other words, it is impossible to fake the seismic signature of an underground explosion, and people will be able to tell if a bomb has been tested and approximately how powerful it is. The reason why underground detonations of nuclear weapons can be detected as earthquakes is due to the fact that in both cases, whether rocks break in an earthquake or during an explosion, very strong forces act quickly inside the Earth. This leads to intense shaking of the rocks around the hypocenter, which in turn generates elastic waves that can travel thousands of miles and be detected by seismometers. Seismometers have been used for a long time to verify nuclear test treaties, and scientists have become increasingly confident that they can detect even small evidence and differentiate it from natural earthquakes.
A nuclear stress test is a medical procedure that uses a radioactive tracer to measure the blood flow to your heart. Learn how long it stays in your system and the risks associated with it.
At present, very little radioactivity can be detected from weapons tests conducted in the 1950s and 1960s in the environment. Learn more about how radiation levels have changed since then and what is currently known about nuclear test sites.
Since 1945, at least eight nations have detonated 2,056 nuclear test explosions at dozens of test sites around the world. The Comprehensive Nuclear-Test-Ban Treaty (CTBT) bans any nuclear weapon test explosion or any other nuclear explosion and established an inter