SO461 Geological Oceanography

Spring 2013 Test 2



4 @ 5 points




4 @ 15 points



Short answer

2 @ 10 points








Authorized reference:

  1. This test will be open book. Students can use their own copy of the textbook, with any notes they have permanently written in it. No papers can be attached to the text, and class notes and handouts will not be allowed. Books will not be shared during the exam.
  2. Calculators will not be allowed. For the calculations, you may set it up and leave the answer in terms of a sum, product, or quotient, or you can make reason simplifications to get a rough idea of the answer.


Definitions: clearly indicate what the term means, and what its importance to geology is.

Diagrams: These should clearly indicate understanding of the procedures and concepts involved, and should be well thought out with appropriate terms and details to support your answer.

Short Answer: The questions should be answered with several sentences (no more than a short paragraph). You must answer four of the five questions.


Budget your time. If you try to look up everything in the text book, you will run out of time. Do not leave anything blank, and note that I am looking for an understanding of the important concepts and appropriate use to terminology. An answer than does this will get more credit than finding and copying a sentence in the book that includes the word.



All work on this exam is individual. You may not any materials (books, notes, computers), not listed above and you may not use IM, texting, talking, or any other means to communicate with other individuals.



Definitions: Fill out the table below for 5 of the 6 terms. Each is worth 5 points, so you should be



Importance to geology







Stage pole 



Large igneous province 



Suspect terrane





Insure one term in left blank or crossed out.

Diagrams. You must answer all of the questions on the next four pages. Each is worth 20 points, so insure that you provide a quality answer.


The diagram below shows the trace of a fault in Western California, in map view. What type of a fault will it be, and what will be the motion along the fault? Sketch a stream that has been offset by the latest fault rupture.






Could the same diagram represent a transform along a mid-ocean ridge? Where would the two ridge segments be located?



Explain why you drew the two diagrams the way you did, what is similar or different between the two cases.





The three maps below show plate boundaries, in map view on the left, and with a velocity diagram on the right. For each boundary, give the type of boundary, and estimate the rate of motion between the two plates. Include the units for the motion. For which (if any) of the boundaries does it make sense to talk about the half rate?


The two cross sections below show two features, drawn with the same horizontal and vertical scales. Note that sea level is shown. Locate at least five features that occur on at least one of the two diagrams, and label themF1 to F5. Suggest somewhere on earth where each cross section could occur, and what you consider to be the key difference between the two.






















The focal mechanism show below all occur near km 700 of the cross section below. Based on this data, discuss what is taking place in this region. In map view, what do you think would be the orientation of the mountain front in the vicinity of the earthquakes?


Short answer. You must answer two of the three questions on the next two pages. Each is worth 10 points, so you should devote an appropriate amount of time.


Fill in the following table with:

                Names for the types of plate boundary

                At least three kinds of igneous rocks, and how/why they form at the boundary indicated.

                At least three kinds of metamorphic rocks, and how/why they form at the boundary indicated.


Plate Boundary

Igneous rocks formed

Metamorphic rocks formed















Drilling cores in the ocean usually includes logs for porosity, density, and sound velocity. Do these vary in a systematic map (why or why not), and for what other studies are these parameters especially important?






Discuss the importance triple junctions and their migration.





Insure that you left one of the short answer questions blank (or crossed out).