At 5:12 a.m. on April 18, 1906, the earth shook violently, waking up the sleeping San Francisco, which lasted about 45 seconds as the precursor of the earthquake. Sure enough, about 10 seconds after the foreshock, a major earthquake of magnitude 8.3 on the Richter scale came, and although it lasted only a minute, it was the biggest nightmare since the founding of San Francisco: the fire caused by the earthquake burned for 3 days and 3 nights, and about 10 square kilometers of urban areas were burned, killing more than 3,400 people and leaving more than 300,000 people homeless, known as the worst natural disaster in American history. The root cause of the earthquake is the San Andreas Fault deep underground in San Francisco.
Dwayne Johnson starred in the disaster film Doomsday Collapse, set in a magnitude 9 earthquake triggered by the San Andreas Fault that stretched from Los Angeles to San Francisco
The power of the flood hidden deep in the earth's crust
In 1906, the cause of the earthquake could only be speculated, and it was not until modern times, with the study of plate tectonics, that we have figured out the truth about the San Francisco earthquake, the San Andreas Fault. The San andreas fault is a fault that comes into contact with the southwest-moving North American Plate and the northwest-moving Pacific Plate, about 1287 km long, about 16 km into the formation, from the vicinity of Lake Salton in the south, all the way north to the west to meet the San Bernardino Mountains, running through the southwest of California (referred to as California), San Francisco and Los Angeles are the two largest cities in this fault zone.
The San Andreas Fault is about 1287 km long and extends into the formation for about 16 km, running through the entire southwestern part of California.
Based on the data of the Global Positioning System for nearly 20 years, as the flat fault (shear) boundary formed by the shear and sliding of the two major plates, the average annual sliding distance of the San Andreas fault is 33 to 37 mm, that is, the "sliding rate" of the fault. This length and speed is enough to prop up the San Andreas Fault as one of the longest and most active faults on earth's surface, the most spectacular of which is the Carrizo Plain, about 480 kilometers south of San Francisco.
The San Andreas Fault is a fault that comes into contact with the North American Plate moving in the southwest direction and the Pacific Plate moving in the northwest direction.
Usually the larger the average slip rate of the fault zone, which means that the boundary channel of the fault is relatively smooth, although there will be no significant effect in the short period, but it also means that the force accumulated by the fault will increase. When the energy generated by the movement of the crust accumulates for a long time in the rock near the fault and reaches a critical point, a certain point on the fault begins to fracture and stagger, and the energy accumulated around it is suddenly released, and the staggered movement expands rapidly along the fault, and the rock bodies on both sides of the fault suddenly slide or jump in the opposite direction, producing a relative displacement, and a large earthquake breaks out.
The Sanandreas fault, which runs through southwestern California, is one of the longest and most active faults on Earth's surface.
Earthquake prediction of the San Andreas Fault
Earthquakes are vibrations of the Earth's surface caused by the sudden release of stresses that slowly accumulate inside the Earth. According to the cause, it can be divided into tectonic earthquakes, volcanic earthquakes, and fall earthquakes. The most important of these are tectonic earthquakes, which account for about 90% of the world's natural earthquakes, and the release energy accounts for about 99% of the total energy of the earthquake, which is also the most destructive earthquake. Tectonic earthquakes occur mainly due to the formation or re-activity of faults in the earth's crust, and the San Francisco earthquake is a typical type of tectonic earthquake.
The San Andreas Fault, which runs through California, has existed for more than 20 million years and is sliding apart at a rate of 33 to 37 millimeters per year
The San Andreas Fault that runs through California, usa, has existed for more than 20 million years, and according to research, the major earthquake cycle caused by the San Andreas Fault is 200-300 years, and two major earthquakes have erupted in northern and central California in the past 1857 and 1906. In particular, the Great San Francisco Earthquake of 1906, although the vertical component is very small, the horizontal direction of the staggering still makes the visible fault line on the surface more than 400 kilometers long, and the fault distance is as wide as 7 meters.
In the 1906 San Francisco earthquake, the horizontal direction of the stagger made the visible fault line on the surface more than 400 kilometers long, and the fault distance was as wide as 7 meters.
Today, the southern san and antilles fault, which has not experienced a major earthquake for more than 250 years, has accumulated an astonishing stress that, if suddenly released, is enough to cause a major earthquake of magnitude 7 or higher on the Richter scale near Los Angeles and San Diego in southern California. And according to the observation of fault movements by current researchers using synthetic aperture radar data, it is shown that a 9.0 magnitude earthquake that may exceed the 1906 San Francisco earthquake has entered the countdown, when the 11.4 million people in California will be plunged into natural division and great threat because of the San Andreas Fault.
If the 9.0 magnitude earthquake of the San Francisco earthquake occurs, 11.4 million people in California will be plunged into natural division and great threat because of the San Andreas Fault.
I just don't know which of the declines and divisions comes first.
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