The Physics Of An Earthquake :: essays research papers

Earthquakes atomic number 18 vibrations piddled in the earths outer layer, or crust, when forces pushing on a mass of tremble overcome the friction holding the rock in place and blocks of rock slip against for each one other. The vibrations can cut back from barely noticeable to verry destructive. There are six types of shock waves. cardinal are classified as body waves which means they travel through with(predicate) the earths interior and the other four are surface waves. The waves are changed by the rock types or formations they hit. Primary or compressional waves (P waves) send particles moveing back and aside in the same direction as the waves are traveling, secondary or transverse shear waves (S waves) send vibrations perpendicular to their direction of travel. P waves forever travel at higher velocities than S waves. Three general classes of earthquakes are now recognized as tectonic, volcanic, and artificially produced. The tectonic variety is by far the most destr uctive. The most commen cause of tectonic quakes is stresses by movements of the dozen of major and minor plates that make up the earths crust . Most tectonic quakes descend at the boundaries of these plates, in zones where one plate slides past some otherSubduction-zone quakes account for nearly half of the worlds destructive seismic events and 75 pct of the earths seismic energy. They are along the so-called Ring of Fire, a specify band about 38,600 km long, that coincides with the sides of the Pacific Ocean. The points at which crustal rupture occurs in such quakes tend to be far infra the earths surface, at depths of up to 645 km. Not all subduction zones are subject to frequent earthquakes.The frequency and order of earthquakes around subduction zones are related to the direction in which the plates are moving. If both plates moving in the same general direction come most together, generally the edge of one plate will slide below the other at a sharp angle. This reduces the amount of area in which the plates touch, so the subduction zone does not produce many earthquakes and any earthquakes it does produce are not as strong. If two plates are sliding beside each other, one plate will often be forced to a lower place the other at a shallow angle, making a big(a) area of friction. This produces more frequent, stronger earthquakes.Tectonic earthquakes beyond the Ring of Fire occur in a variety of geological settings.