What is the difference between an earthquake “epicenter” and an earthquake

What is the difference between an earthquake “epicenter” and an earthquake

Question
1) Go visit
.usgs.gov/”>http://neic.usgs.gov/
(and/or other suitable web sites that detail recent earthquakes)
Find info on a recent earthquake, greater than magnitude 5.

Now, describe the following…
A) Where did it occur? B) When did it occur? C) Magnitude and Effects? D) Tectonic setting? (Tectonic setting= type of plate boundary, or intra-plate.)

2) What is the difference between an earthquake “epicenter” and an earthquake “focus”?

3) Waves in the ocean are generally made by wind. Tsunami are different!

How do the wave-heights (“amplitude”) AND wave velocities of typical tsunami compare to wind-generated waves?

4) Why is carbon dating (utilization of C-14 to C-12) technique not very useful for rocks, or for any materials older than a couple hundred thousand years?

5) Let’s say that I grind up a detrital sedimentary rock and put it into a “radiometric dating machine.” Is the date that I obtain very useful?
(Two hints: Under “uses of isotopic dating” your textbook states that “sedimentary rocks are difficult to date reliably”—why? AND—Think about what detrital sedimentary rocks are composed of.)

6)OK, let’s say that you want to figure out how old a sedimentary rock is! One way would be to look at igneous layers either above or below (or cross cutting dikes). Another way would be to use Index Fossils. Please define what we mean by “INDEX FOSSILS” are AND explain how they are used in determining sedimentary rock ages.

7)Let’s say that one meter (100 cm) represents a time-line for the entire 4.5 billion year span of earth history. How far along the meter stick would one find the boundary between the “Precambrian” and the “Phanerozoic”?

8)Review the section in your Earthquake chapter titled “Subduction Angle.” Now consider this question:
When the Rocky Mountain rose, starting about 70 my ago, subduction of the Farallon oceanic plate beneath North America involved a high rate of subduction and a mid-ocean ridge that was close to the subduction trench. This is further detailed in the video—Rocky Mountain Uplift Part 2
Recognizing that this proximity of the newly formed ocean crust to the subduction trench means that the descending plate was relatively warm….decide whether or not the subduction angle at that time would have been steep or shallow. Please explain your reasoning.

9)Unconformities are challenging for geologists. They are like missing pages in the book of earth history, which we are trying to read! Please review sections on unconformities in your text.
Which type of unconformity (angular, nonconformity, or disconformity) is probably the most difficult to recognize when looking at a cross-section of rock out in the field?

10)Assume that you have 100 pounds of radioactive Lesterium (a radioactive element named after me…sorry, you won’t find it in the periodic table!). It has the convenient half life of ONE year.
Based on the concept of half-life, after one year you’ll have 50 pounds are left.
After two years, you’ll have 25 pounds left.

Will a time come when there is absolutely zero left? Yes, No? Explain.