SO503 Exam 2, Spring 2016

All work on this exam is individual. You may use any materials (books, notes, computers, calculators, web sites), but you may not use email, IM, texting, talking, or any other physical or electronic means to communicate with other individuals either local or remote.

Get this data file with earthquake data for September 2013.  The original source of the data is at http://www.globalcmt.org/CMTfiles.html.
There are other sources of earthquake data that would be easier to use; this format has detailed information on the geometry of the fault surface and provides a wealth of information for plate tectonics (and SO461 if you were to take it and come to  love beach balls).

Here is a description of the ndk format.  Note that each earthquake has five lines of data, and you only need a few of the values.

Do the following, all in Matlab code (your code should work with another file with >40K earthquakes)

• Find the number of earthquakes in this database.
• Plot on a map the locations of
• all earthquakes during this month
• all the earthquakes deeper than 200 km
• Find the location of the largest earthquake during this month.  Note that there are potentially two magnitudes reported; use mb if available; otherwise use MS
• Create a scatterplot showing the relationship between the two magnitudes mb and MS for all earthquakes that have valid values for both
• Create a table or a graph with the azimuth distribution of the largest force that created the earthquake
• This will be on the last line in the data record, and is the fourth value in the line (columns 16:18).  It is described as the "moment tensor" which describes the 3D distribution of forces that caused the earthquake; you are just extracting one of the values in that tensor (=matrix).

Turn in:

• Single Word document
• Sentence with the number of quakes, and location of the largest.
• Figures and tables, properly captioned.