Essentially, the damage caused by earthquakes depends
on the characteristics of the ground in that area. For example, earthquake
vibrations last longer and are of greater wave amplitudes in unconsolidated
surface material, whereas bedrock areas receive fewer effects. The
worst damage from an earthquake occurs in densely populated, urban areas,
where structures are not built to withstand intense shaking.
(Goldstein, "Earthquakes Museum")
In fact, two of the most popular places for intense
earthquake activity are California and Japan. California
is the most populous state in the union, and it has the most earthquakes.
In this area, as the tectonic plates move in relation to each other along
the faults, they slip, or move laterally past one another.
On the other hand, Japan, also known as "The World's Earthquake Factory,"
is one of the most earthquake-prone countries in the world.
Japan has 30 times the population density as the United States; therefore,
the seismic activity in this location proves much more disastrous.
In this area of the world, as the tectonic plates move in relation to each
other along the faults, they converge, or bump into one another,
with one plate usually sliding beneath the other in the subduction
zone. (Stewart and Knox)
Ultimately, however, both California and Japan are areas of the world that have experienced tremendous amounts of damage due to extensive and frequent seismic activity, or earthquakes. This is true because both locations are located on the "Ring of Fire," which loops around the Pacific Basin. This "Ring of Fire" is related to the movement of huge tectonic plates, or blocks of the earth's crust, that bump and slide past each other like gigantic ice flows. The graphic below highlights the different areas that are located in this dangerous zone. (Iacopi)
As a result of their dangerous and active locations
on the Pacific Basin, both California and Japan share parallel physical,
structural, and emotional damage patterns. A brief synopsis includes..sections
of elevated freeways buckle and collapse, inadequately reinforced structures
topple, liquefaction occurs in the epicental area, major dislocation of
utilities causes fires and hampers rescue efforts, and combined vertical
and horizontal stresses placed on older structures create large-scale disaster.
TABLE OF CONTENTS:
For example, this map shows the epicenter of the Northridge, CA earthquake (star), the limit of the landslides triggered by the earthquake (heavy, solid line), and the area of greatest landslide concentration (shaded). Overall, the earthquake that occurred in Northridge triggered 11,000 landslides. ("Earthquake Induced Mass Movement")
For more information and pictures depicting earthquake-induced
landslides, see link: Earthquake Induced Mass Movement(http://www.aber.ac.uk/iges/cti-g/hazards2000/massmovement/tectonic.html)
name for "Harbor wave," or seismic sea wave.
Alone with his destiny, a man stands transfixed before
a world of water (55 foot killer wave) about to engulf him.(Walker)
Tsunamis are the result of a sudden vertical offset in the ocean floor, which can indeed be triggered by intense earthquakes. Essentially, tsunamis are creatures of the open ocean, or trains of great waves that can travel long distances across the sea. As a tsunami approaches the shore, the water depth decreases, the front of the wave slows down, and the wave grows dramatically in height and surges unexpectedly onto the land. Truthfully, tsunamis can carry a considerable amount of energy because they possess strong currents that cause massive erosion of the coastline, as well as bulldoze towns and drown unsuspecting, curious people. When earthquakes occur, these dark "walls" of water suddenly flood coastal areas like California and Japan without warning. For example, in 1896, an earthquake off of the coast of Japan generated an enormous tsunami with waves up to 100 feet high. This "wall of water" killed 22,000 people and destroyed entire villages.
***FIRES: result from broken or severed electrical and gas lines.
Fires that begin as a result of earthquake activity are often uncontrollable and can cause the most damage. Flammable materials or debris released from the earthquake feed the flames of the fire, thus causing it to spread out of control. Water mains are broken as a result of the powerful earthquake vibrations, therefore, no water is available for firefighters to put out the flames and rescue the people. For example, in the 1906 earthquake in San Francisco, California, fire caused the most damage because the broken water mains and blocked roads allowed the flames to swell out of control. (Gilfond)
This photo depicts the horrific scene in Fukui, Japan
after a severe earthquake hit. As the picture illustrates, an uncontrollable
fire unleashed lethal flames that consumed the helpless town. (Walker)
***MUDSLIDES: slip down mountain slopes, sweep main valley floors, and bury habitations below.
The graphic shown above illustrates how the clay-free soil deposits, consisting mostly of sands and silts, can flow much like quick sand in the event of a strong earthquake. (Iacopi)
For more information (and pictures) about how soil
can act like a fluid during strong earthquakes, see link: Liquefaction
***BUILDINGS COLLAPSE: seismic vibrations that occur during earthquakes cause buildings to sway, which may knock them off of their foundations and cause severe damage or destruction. People can be trapped in collapsed buildings or under rubble that collapses into the street.
Extensive property/roadway DAMAGE in Kobe,
***DEATHS.people become trapped under the rubble and debris that is generated from the earthquake. Falling structures and flying glass and other objects strike unsuspecting people.