1988 Armenia Earth Quake
Vol 39 No 2, April - June 2001 Page 48 The earth is not a static planet; the large slabs of the earth’s crust (tectonic plates) are in continual slow motion. An earthquake occurs when these plates move. The movement causes rock to be squeezed, bent, and stretched. This tremendous pressure eventually forces the rock to break, and the plates lurch into a new position. The underground place where the rock moves or breaks is called the focus. The epicenter is the area directly above the focus on the earth’s surface. These movements cause large fractures, or faults, in the earth’s crust, and along these fault lines most earthquakes occur. The adjustments that follow a major earthquake often generate smaller quakes called aftershocks. Aftershocks, or tremors, are usually much weaker than the main series of quakes and ... [Read More]
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