Seismic wave Seismic wave Seismic waves are waves of energy that travel through the Earth's layers, and are a result of earthquakes, volcanic eruptions, magma movement, large landslides and large man-made explosions that give out low-frequency acoustic energy. Many other natural and anthropogenic sources create low-amplitude waves commonly referred to as ambient vibrations. Seismic waves are studied by geophysicists called seismologists. Seismic wave fields are recorded by a seismometer, hydrophone (in water), or accelerometer. The propagation velocity of the waves depends on density and elasticity of the medium.Velocity tends to increase with depth and ranges from approximately 2 to 8 km/s in
Tunnel effect Tunnel effect In experimental psychology, the tunnel effect is the perception as a single object moving beyond an occluding object and then reappearing after a suitable amount of time on the other side of it. This phenomenon has been studied by Burke (1952), who discovered that the optimal amount of time for giving the impression of a single object is shorter than what is actually needed to cross the occlusion at that speed. The "tunnel effect", when talking about long stretches of road, refers to the environment surrounding the driver that begins to merge towards the central point of the