1906 Earthquake

824 Words4 Pages
How the 1906 Earthquake Marked the Dawn of Understanding Earthquakes And the Study of the San Andreas Fault in California On the morning of April 18, 1906 at approximately 5:12 in the morning, the city of San Francisco was awoken to one of the most devastating earthquakes in the history of California. The earthquake and subsequent fires caused an estimated 3,000 deaths and over half of the city’s residents were left homeless, and the once wealthiest and most important cities on the Pacific Coast was turned to ashes and ruins (Zoback). Before 1906, little was known or understood about earthquakes, how and where they occurred, or the risk they posed. Although the 1906 earthquake manifested a groundbreaking and tragic event in California,…show more content…
Thus, the Commission established the San Andreas Fault as a “continuous geologic structure extending for over 600 miles throughout much of California” (Zoback). Triangulation surveys, which are “optical measurements that detect changes in the angles between lines connecting monuments fixed in the ground,” proved to be one of the most noteworthy observations made after the earthquake of 1906 (USGS). Displacements in the earthquake were found, and the largest were observed at the fault and “decreased with distance from it, so that a previously straight line crossing the fault had become curved” (USGS). Ultimately, these observations led to the “theory of elastic rebound,” which was initiated by Professor H.F. Reid of John Hopkins University who had also served on Lawson’s Commission (Zoback). This theory is so important…show more content…
Before the 1906 earthquake, this basic theory that “the faulting causes the earthquake, the earthquake does not cause the faulting,” was not a universal opinion geologists applied to the San Andreas Fault. This hypothesis is now accepted today, although the basis for “large-scale horizontal displacements wasn’t established until the plate tectonic revolution more than 50 years later” (Zoback). Overall, the knowledge and understanding that derived from the studies of the 1906 earthquake founded numerous philosophies that underlie present day seismic hazard assessment. Just few
Open Document