Earthquake

Earthquake

Identify Different Natural Disasters

Floods

Floods are the most common and widespread of all natural disasters--except fire. Most communities in the United States have experienced some kind of flooding, after spring rains, heavy thunderstorms, or winter snow thaws.

Hurricane

A hurricane is a tropical storm with winds that have reached a constant speed of 74 miles per hour or more. Hurricane winds blow in a large spiral around a relative calm center known as the "eye." The "eye" is generally 20 to 30 miles wide, and the storm may extend outward 400 miles. As a hurricane approaches, the skies will begin to darken and winds will grow in strength. As a hurricane nears land, it can bring torrential rains, high winds, and storm surges. A single hurricane can last for more than 2 weeks over open waters and can run a path across the entire length of the eastern seaboard. August and September are peak months during the hurricane season that lasts from June 1 through November 30 (Deborah, 2012).

Earthquake

An earthquake is a sudden, rapid shaking of the Earth caused by the breaking and shifting of rock beneath the Earth's surface. For hundreds of millions of years, the forces of plate tectonics have shaped the Earth as the huge plates that form the Earth's surface move slowly over, under, and past each other. Sometimes the movement is gradual. At other times, the plates are locked together, unable to release the accumulating energy. When the accumulated energy grows strong enough, the plates break free causing the ground to shake. Most earthquakes occur at the boundaries where the plates meet; however, some earthquakes occur in the middle of plates.

Many earthquakes occur as a result of movement along pre-existing faults or fractures occurring in the earth's crust (e.g. along plate margins). Forces of tension and compression created in the earth's crust largely due to tectonic movements of the plate produce sudden movements along the line of fracture (fault lines) resulting in two blocks of crust slipping with respect to each other. This sudden movement produces seismic waves which travel from the source through the crust to the earth's surface. When they arrive, the vibratory motion felt is called an earthquake (Deborah, 2012). 

The Caribbean Plate interacts with the North-American Plate at its eastern boundary, where the Atlantic sea floor attached to the North American and South American Plate is being forced or subducted beneath the Caribbean Plate. The subducted material underwent partial melting which because of its then less buoyant nature was, sometimes forced to the surface in the form of volcanic activity to produce the chain of Caribbean islands. 

This process of subduction is still occurring and is largely responsible for the seismicity felt today in these islands. In addition, the sometimes slow, upward, less violent intrusion of molten magma into the crust of these active volcanic areas produces seismic activity which is felt on the surface asearthquakes. 

Effect of Earthquake

An earthquake's magnitude is measured using the Richter Scale, developed by Charles F. Richter in ...