By this time, scientists were well aware of the threat, but seismology was still in its infancy. While the 1812 San Juan Capistrano, 1857 Fort Tejon, and 1872 Owens Valley shocks were in mostly unpopulated areas and only moderately destructive, the 1868 Hayward event affected the thriving financial hub of the San Francisco Bay Area, with damage from Santa Rosa in the north to Santa Cruz in the south. Since the three damaging earthquakes that occurred in the American Midwest and the East Coast ( 1755 Cape Ann, 1811–12 New Madrid, 1886 Charleston) were well known, it became apparent to settlers that the earthquake hazard was different in California. From 1850–2004, there was about one potentially damaging event per year on average, though many of these did not cause serious consequences or loss of life. After the missions were secularized in 1834, records were sparse until the California Gold Rush in the 1840s. As Spanish missions were constructed beginning in the late 18th century, earthquakes records were kept.
Ship captains and other explorers also documented earthquakes. state of California was documented in 1769 by the Spanish explorers and Catholic missionaries of the Portolá expedition as they traveled northward from San Diego along the Santa Ana River near the present site of Los Angeles.
The earliest known earthquake in the U.S.
0 kommentar(er)
