Geological Disasters and Society
Earthquakes

1. (2 pts.) Explain, in your own words, the difference between a natural disaster and a natural hazard. Provide two specific examples of each, besides ones mentioned in class or in the posted summary slides.

2A. (3 pts) Draw a sketch of a cross section of the earth, showing (and naming) the 3 major density (composition) layers. Include the approximate thicknesses of each layer and the approximate density ranges for each layer.

2B. (3 pts) Plate tectonic hazards depend much more on the strength layering (strong lithosphere made up of crust plus uppermost mantle over weak, but not molten, asthenosphere) of the Earth than the density/composition layering in 2A. Draw a sketch of the outer ~350 km of the Earth away from any active plate boundaries that includes both oceanic and continental lithosphere. On the sketch label the parts that correspond to oceanic crust, continental crust, mantle, lithosphere and asthenosphere. Indicate approximate thicknesses for each layer.

3. (5 pts) Of the three types of plate boundaries (spreading/divergent, transform, convergent/subduction), which type of plate boundary produces the largest earthquakes? Draw a cross-section (not a map view) of this type of plate boundary (make your own sketch). Give two examples of such earthquakes in the last 10 years, including location, date, and magnitude.

5. (10 pts) Choose an earthquake (Magnitude > 6.5, that caused significant damage and/or loss of life in some populated region of the world) from the list below. Type a one page, double-spaced, write-up on the earthquake that includes citations. Address as many of the following items as possible:
- Plate tectonic setting of event (Is it associated with a plate boundary and if so what kind, and what plates are involved?).
- Earthquake size (magnitude).
- Associated hazards (strong ground shaking, tsunami, fires, landslides, liquefaction, etc.).
- Main causes of death (number of fatalities) and property damage (estimated cost).
- Actions that could have reduced the losses.

Geological Disasters and Society Earthquakes 1. (2 pts.) Explai...