OLD MCQ Flashcards
Describe a cross section of the earth state
earths surface, mostly solid, liquid, solid
During which process are the heaviest elements in the Universe made?
Supernovae explosion
How do scientists gather evidence about whether the very center of Earth is mostly a solid, a liquid, or a gas?
Tracking how seismic waves move through Earth
What are the principle features of continental crust? (thickness, makeup, ages, density, minerals)
25-60 km thick.
Mainly sedimentary, metamorphic rocks and granites/rhyolites.
Ages span the whole of Earth history.
Average density 2.7 grams per cubic centimeter.
Rich in Si, Al.
The lithosphere and the asthenosphere are two layers of Earth that are defined by their:
deformation behavior
What is an accurate description of how plate motion is accommodated in New Zealand?
About 30% of Australia-Pacific plate motion is localized outside of the principle plate boundary faults, on faults with low slip rates found throughout New Zealand.
You discover a paleochannel (old stream bed) preserved in a fault scarp which is offset 50m from where the present-day stream channel cross-cuts the fault scarp. Radiometric dating tells you the paleochannel is 1,800 years old (i.e. it was offset approximately 1,800 years ago). What is the approximate slip rate on this fault?
28 mm/yr
How do you figure out the recurrence interval for earthquakes on this fault?
The recurrence interval is the time that has passed between earthquake events (in years). You need to date at least two consecutive earthquake deposits and determine how much time passed between each earthquake.
The general correlation between earthquake magnitude and the total number of earthquakes in a given region is called the Gutenberg-Richter relationship. What does the Gutenberg-Richter relationship indicate?
That lower magnitude earthquakes generally occur more frequently than higher magnitude earthquakes.
What is risk?
risk = hazard + exposure
