San Francisco ... North American and Pacific tectonic plates had moved past each other by more than 15 feet — compared to an annual average of two inches. The earthquake is estimated to ...

San Francisco ... North American and Pacific tectonic plates had moved past each other by more than 15 feet — compared to an annual average of two inches. The earthquake is estimated to ...

The Earth's plates jostle about in fits and starts that are punctuated with earthquakes and volcanic ... of the plates creates three types of tectonic boundaries: convergent, where plates move ...

Hamilton obtained the only good record of local strong ground motion from the great earthquake that devastated San Francisco that day. Astronomers at Lick Observatory ... who found the tracing in the ...