7.4.2: Historical Background
- Page ID
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For most of recorded history, earthquakes were regarded as unpredictable calamities, acts of God—not subjects for government involvement except for dealing with the consequences. This began to change in 1891 when a killer earthquake devastated a large section of western Japan at the same time Japan was gearing up its economy to become an equal partner and competitor with Western countries. After the 1891 earthquake, the Japanese government authorized a long-term earthquake research program, including the mapping of active faults after a major earthquake, the deployment of seismographs (which had recently been invented), and the resurvey of benchmarks across active faults and along coastlines to look for crustal deformation. The Earthquake Research Institute was established at the University of Tokyo.
As a result, Japanese earthquake scientists became world leaders. Fusakichi Omori, at the time regarded as the world’s leading seismologist, participated in the investigation of the 1906 San Francisco Earthquake. Kiyoo Wadati invented a magnitude scale before Charles Richter developed the scale that bears his name. Wadati also was the first to recognize earthquakes hundreds of miles beneath the Earth’s surface, outlining what would later be known as subduction zones. Two of the leading seismologists in the United States are transplants from Japan: Hiroo Kanamori of Caltech, and the late Keiiti Aki, who had recently retired from the University of Southern California.
In the early twentieth century, seismograph observatories were established at the University of California at Berkeley, Caltech, Victoria, Seattle, and other places around the world. The Jesuits were important players, with a seismograph at Gonzaga College in Spokane, Washington. Seismology developed primarily as an academic pursuit, with earthquake research intertwined with using earthquake waves to image and explore the internal structure of the Earth. At the time of the 1949 Puget Sound Earthquake, the University of Washington had only one recently hired faculty member in seismology who was in the process of building a new seismograph in the sub-basement of the geology building, using state funds. This young man suddenly found himself in the glare of the public eye, trying to answer questions of what, where, and why.
The first federal funding for earthquake-related research was to the U.S. Weather Bureau, which was given the assignment of collecting earthquake observations at its weather stations. The monthly weather review of the chief signal officer of the War Department was first published in 1872, and earthquake reports appeared as early as 1882. The Weather Bureau issued its own report on the 1906 San Francisco Earthquake. In several countries around the world, including Japan, the national weather service still has a major responsibility in monitoring earthquakes.
Resurveying benchmarks in California by the U.S. Coast and Geodetic Survey (later the National Geodetic Survey) led to Professor Harry Reid’s elastic rebound theory for the 1906 San Francisco Earthquake on the San Andreas Fault. Both the Coast and Geodetic Survey and the Weather Bureau were part of the Department of Commerce, the only part of the federal government with a mandate to do anything at all about earthquakes. A triangulation survey by the Coast and Geodetic Survey authorized by Secretary of Commerce Herbert Hoover in the 1920s confirmed Reid’s observation that the area adjacent to the San Andreas Fault was continuing to build up strain even as it had done before the 1906 earthquake.
Aside from that, the U.S. government stayed away from earthquakes. In large part, this was because earthquakes were perceived as a California problem, and California business and political leaders played down the threat from earthquakes because they were bad for business and particularly bad for the real estate speculation boom that was then going on. The investigation of the 1906 San Francisco Earthquake was paid for not by the government but by a private organization, the Carnegie Institution of Washington. The statements of the scientists, including those of Professor Omori, were taken out of context by the media to give the impression that the San Francisco disaster was a fire rather than an earthquake. This included a coverup: many more people died than the official documents claimed. Accordingly, no lessons were learned, and no attempts were made to strengthen buildings against earthquakes.
One positive outcome was the founding of the Seismological Society of America (SSA) in the San Francisco Bay Area, an organization that took an active role in earthquake safety. However, other SSA members were engaged in the investigation of the internal structure of the Earth, using seismic waves in the same way doctors were using Xrays to view the bone structure of the human body. These seismologists viewed the SSA as an association of academics and research scientists, and some of them were uncomfortable with the SSA taking a more political role in advocating earthquake safety.
This continued through the Roaring Twenties, during which business leaders downplayed an earthquake that heavily damaged the resort city of Santa Barbara in 1925. However, by this time, scientists were better organized, and the first building codes were enacted by the cities of Santa Barbara and Palo Alto, the latter city the home of Stanford University, the site of much advocacy of earthquake preparedness. In 1933, the Long Beach Earthquake trashed many school buildings in the Los Angeles area, leading to state legislation mandating earthquake standards for school buildings. Still, the federal government stood on the sidelines.
This changed dramatically when the Soviets successfully tested nuclear weapons following World War II. Federal funding for seismology was not due to any concerns about earthquake hazards, but was driven by the Cold War. The United States and its NATO allies wanted to monitor Soviet (and later, Chinese) underground nuclear tests using seismographs. Seismologists showed that it was possible to distinguish between seismograms written by earthquakes and seismograms resulting from nuclear explosions, and also to determine the size and location of an underground nuclear test, just as seismologists are able to determine the magnitude and location of an earthquake.
By the early 1960s, the United States, in cooperation with other Western countries, had established a worldwide seismograph network (WWSSN), to monitor the testing of nuclear weapons, particularly after the signing of the Nuclear Test Ban Treaty in 1963. The WWSSN had a spectacular, serendipitous scientific payoff. By allowing the world’s earthquakes to be located much more accurately than before, the network provided evidence that these earthquakes follow narrow bands that were found to be the boundaries of great tectonic plates (Chapter 2, Figure 2-5). By 1966, the plate tectonics revolution had overturned the prevailing view of how the Earth works, and seismology, because of the WWSSN, had made a major contribution.
The U.S. Geological Survey (USGS) had carried out detailed investigations of major earthquakes in Charleston, South Carolina, in 1886 and in Alaska in 1899, and continued with USGS scientists participating in investigations of the 1906 San Francisco Earthquake and the 1959 Hebgen Lake Earthquake near Yellowstone Park. A team of seismologists had been assembled by the USGS in Denver to monitor the nuclear test ban. These seismologists were moved to Menlo Park, California, where they joined a team of geologists studying the great 1964 Alaska Earthquake. In carrying out these studies, the USGS was following in the tradition of the Geological Survey of India, which had studied in detail great Himalayan earthquakes in 1897, 1905, and 1934. Involvement of the USGS continued and accelerated following earthquakes in California in 1968 and 1971.
However, there was still no federal mandate for the USGS to take over the investigation of earthquakes. The only federal agency with earthquake responsibilities was still the Department of Commerce through the Weather Bureau and the Coast and Geodetic Survey. In 1947, the Coast and Geodetic Survey asked California structural engineers for advice in setting up strong-motion seismographs, and in designing buildings to be more resistant to earthquake shaking (as well as a nuclear explosion). The engineers formed an Advisory Committee on Engineering Seismology, which by 1949 became the Earthquake Engineering Research Institute (EERI), which became a link between the SSA and professional engineering organizations. This was important because of an ongoing debate among structural engineers between those favoring more earthquake-resistant construction and those concerned about the increased costs of those measures.
Clearly, the Department of Commerce intended to keep its mandate to study earthquakes, particularly after the 1964 Alaskan Earthquake and the 1971 Sylmar Earthquake in a suburb of Los Angeles. USGS scientists had a strong interest in these earthquakes, but they could fund investigations only out of their own limited budgets, which commonly were based on the search for increased mineral resources. The Department of Commerce and the USGS issued separate government reports on each of these earthquakes.