EESC1168 Lecture Notes - Lecture 15: San Andreas Fault, Sagami Bay, Plate Tectonics
21 Feb 2017
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Document Summary
Approximately 2 million earthquake deaths from 1900-2000. Most deaths due to two extremely destructive quakes: This fits the pattern from friday of a few high magnitude quakes, and many small ones. The edges of tectonic plates are rough and irregular, so the plates cannot slide smoothly past each other. Stress builds up until it is released suddenly, causing an earthquake. The hypocenter was 6-9 miles below the surface. 1848: gold discovered in the sierra nevada mountains. Mined gold and silver coins, banking, and trans-pacific trade. The 1865 and 1868 quakes destroyed buildings and sparked fires. Little emphasis on building code enforcement; people rebuilt and moved on. Poorly constructed buildings and those on landfill ( made land") or alluvial plains destroyed. Land created by sediment deposits from rivers (an alluvial delta, or alluvial plain) acts in a similar way to land created by pushing debris in the ocean.
