Question 1
The position on Earth's surface directly above the earthquake source is called the ________.
◦ inertial point
◦ focus
◦ seismic zone
◦ epicenter
Question 2
Earthquakes along the San Andreas fault zone, for example, are repetitive–they reoccur in roughly the same regions over and over again–separated by decades or centuries because ________.
◦ stress continues to build up all the time and when it is great enough to overcome friction there will be an earthquake and then the process will start over again
◦ faults are always moving or creeping so an earthquake will occur whenever two sides meet that have the right properties for an earthquake
◦ plate boundaries move at regular rates so the interactions across plate boundaries are predictable and regular
◦ there are areas that are weak and always break when small amounts of energy are applied to them