Physical and Technological: What happened in a flood or earthquake?10
Politics: What role did politics play in the incident?10
Law and Litigation: What laws were violated?10
Critical Incident: Was it or was it not?11
San Francisco Earthquake, 1906
One of the most significant earthquakes of all the times is the earthquake that shook California on the morning of April 18, 1906. It was such a massive earthquake that even lasting only less than a minute, its instant shock was disastrous. The earthquake caused ignition of numerous fires across the city that set ablaze for three days and wiped out almost 500 city blocks. The earthquake was responsible for the rupturing and snapping of northernmost of the San Andreas Fault from triple junction at Cape Mendocino to the northwest of San Juan Bautista. The earthquake discombobulated contemporary geologists due to its great displacements horizontally and large rupture length that is around 296 miles (477 kilometers). The importance of the fault and identification of its extensive cumulative offset would not really be entirely recognized until the proposition of plate tectonics over half a century afterward. Investigation of the displacements by San Francisco earthquake in 1906 and devastation in the skirting crust directed an eminent geologist Reid to develop his elastic-rebound theory illustrating the cause of the earthquake. The theory is still the major model of the earthquake cycle.
An earth tremor fell out with adequate force to be experienced extensively across the San Francisco Bay area at approximately just 5:12 a.m., local time. Some 20 to 25 seconds later, the enormous earthquake broke loose, with an epicenter close to San Francisco; near Mussel Rock that just two miles ahead of the city center of San Francisco. Aggressive shocks disrupted the strong trembling which ended some 45 to 60 seconds. The earthquake was experienced in a wide area from southern Oregon to south of Los Angeles and inland to central Nevada. The maximum MMI's- Modified Mercalli Intensities of VII to IX collimated the extent of the rupture, covering as far as 80 kilometers inland from the fault outline. One significant feature of the trembling intensity illustrated in Lawson's report brought out in 1908 was the apparent association of intensity with underlying conditions of geology. Areas located in sediment-filled valleys undergo stiffer vibration as compared to the close bedrock sites, and the strongest trembling happened in areas where ground repossessed from San Francisco Bay miscarried in the earthquake. Current practice of seismic zonation describes for the dissimilarities in seismic vulnerability caused by contrasting geologic conditions.
The earthquake was massive in strength caused extensive fatalities, economic losses and destruction. Furious fires were also caused by earthquake that combusted for at least four days because of poorly broken and ruptured gas pipes. The consequential firestorm damaged people and property in a similar way. The water pipes too failed causing water tremendously scant and almost ...