DEATH TOLL The earthquake caused 5100 deaths, mainly in Kobe. The Hanshin earthquake was the worst earthquake in Japan since the 1923 Tokyo earthquake, which is also called the Great Kanto earthquake. The Great Kanto earthquake claimed 140,000 lives. On the other hand, the Kobe region was thought to be fairly safe in terms of seismic activity. STRUCTURAL DAMAGE The cities of Kobe and Osaka are connected by an elevated highway.
It also destroyed a lot of property which is estimated to be about $6 billion. This is the biggest earthquake ever to occur and recorded along the fault lines of San Andreas from the previous massive earthquake back in April of 1906. Most of the property devastation that was caused by the earthquake happened in the Oakland and also in San Francisco areas that were about 100 kilometers northwards from the fault line where the section moved in the San Andreas region. A lot of houses collapsed while several reinforced –concrete viaducts were destroyed in four areas of Oakland and also San Francisco. The areas namely: Embarcadero Freeway, Nimitz Freeway, which is in Highway 10, Oakland and the Interstate 280.
At least six of the injuries were classified as critical. In Vallejo, 49 people were injured, including two who were hospitalized. One person died September 5 as a result of injuries from the quake. Following the earthquake, several older commercial buildings in downtown Napa showed signs of extensive external damage even though many had been retrofitted for earthquake safety protection. All of these buildings are listed on the National Register of Historic Places.
The earthquake occurred in the backarc region of the convergent boundary where the Pacific Plate subducted beneath the Eurasian Plate. The earthquake shaking caused moderately severe damage, VIII on the Mercalli scale. The jolting movement of the seabed made the water rise and fall, which set off a terrifying tsunami. The fast-moving waves spread in all directions. They hit Okushiri less than four minutes later.
What makes a building or structure fail in earthquakes? An Earthquake moves the ground. It can be one sudden movement, but more often it is a series of shock waves at short intervals, like our ripples from the pebble in the pond analogy above. It can move the land up and down, and it can move it from side to side. All buildings can carry their own weight (or they would fall down anyway by themselves).
The point on the Earth's surface directly above the hypocenter is called the epicenter of the earthquake. The closer you are to the epicenter of the earthquake, the more dangerous and devastating. The severity of an earthquake can be expressed in terms of both intensity and magnitude. Although the two terms are very different, they are often confused with each other. Intensity is based on the observed effects taken place during the earthquake, for instance the ground shaking underneath people, buildings, and natural features.
The Sichuan 2008 Earthquake Factors On 12 May 2008 at 14:28:01.42 CST, an earthquake, measuring up to 8.0 on the Richter scale struck the Wenchuan County of the southwest Sichuan province of China. The epicentre location was 31°01’16”N and 103°22’01”E. Between 64 and 104 major aftershocks, ranging in magnitude from 4.0 to 6.1, were recorded within 72 hours of the main quake. According to Chinese official counts, by October 23, there had been 34,498 total aftershocks. By September 2008, the recorded number of dead was 69,227, with 374,643 injured, 17,923 missing and at least 5 million homeless.
The actual speed of P and S seismic waves depends on the density and elastic properties of the rocks and soil through which they pass. In most earthquakes, the P waves are felt first. The effect is similar to a sonic boom that bumps and rattles windows. Some seconds later, the S waves arrive with their up-and-down and side-to-side motion, shaking the ground surface vertically and horizontally. This is the wave motion that is so damaging to structures.
A tsunami “wave train” may come as surges five minutes to an hour apart. The cycle may be marked by the repeated retreat and advance of the ocean. Despite a lag of up to several hours between the earthquake and the impact of the tsunami, nearly all of the victims were taken completely by surprise because there were no tsunami warning systems in the Indian Ocean to detect tsunamis or to warn the general populace living around the ocean. The Indian Ocean tsunami travelled as far as 3,000 miles to Africa and still arrived with sufficient force to kill people and destroy property.
This is an analysis on what is known to be the largest earthquake and biggest tsunami ever to hit Japan on March 11, 2011. The earthquake and tsunami Japans coast lies in ruins after the earthquake hit followed by the tsunami picking up everything in its path like cars, houses, and warehouses. Seismometers, strain gages, and title gages records the disaster. P-waves travel at four miles a second and within seconds warnings flash across the country. The S-waves shake the ground making earthquakes so damaging and the reactor core is shut down (Kerger, 2011.