Historic Shipwrecks

Spring 2016

Gold Science Exam

 

Definitions (7/12)

7 @ 4 points

28

 

Short answer (3/4)

3 @ 8 points

24

 

Diagrams (4/5)

4 @ 12 points

48

 

Total

 

100

 

 

No Authorized references.

 

You have choices.  Use them wisely, and insure you understand the questions you choose to answer.

 

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.  You must answer four of the five questions.

 

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.   Do not leave anything blank, and note that I am looking for an understanding of the important concepts and appropriate use of terminology.

 

All work on this exam is individual.  You may not any materials (books, notes, computers, etc.), and you may not use IM, texting, talking, or any other means to communicate with other individuals.  If you are caught with an electronic device that is not turned off and inaccessible you will get a 0 on the exam.

 


Definitions/Terms:  Define 7 of the 12 terms.  You should have 2 sentences for each, and clearly define what the term means, and then explain why it is important in the context of searching for investigating shipwrecks.  Because you have a choice, I expect very high quality on your answers, so select terms on which you can shine.

 

1.      Fluyt:

2.      Geoid:

3.      Induced versus remnant magnetization:

4.      Layback:

5.      Lidar:

6.      TWTT:

7.      Dry monsoon:

8.      Cross track direction:

9.      Monte Carlo simulation:

10.  1500 m/sec

11.  Multibeam bathymetry

12.  Leeway

 

Insure that you only answered 7 definitions.



Short answer.  You must answer 3 of the 4 questions

 

 

 

How does a lead line work, and how effective is it?

 

  

How can we use a satellite to measure depths in the ocean?  What are the tradeoffs from this method, and is it sufficient when we must find a lost object like the MH370 aircraft?

 

 

What does a magnetometer measure, and what can we locate with it?  Would it be better for a steel warship or an aluminum aircraft?  Would you get better results using an aircraft or towing it behind a ship—give one reason why you might prefer each.

 

Differentiate 2.5 D and 3 D data sets,  how they might be collected and used in a marine survey, and how they would be displayed differently

 

 

Insure that you answered 3 of the 4 questions in this section


 

Answer 4 of the 5 diagrams.

 

 

This image shows a side scan sonar image.

 

Can you tell which way the ship moved?  Why or why not?

 

What factors determine the strength of the return measured by a sidescan sonar, and what will produce the strongest return for each factor?

 

Discuss two things you can see in the image.

 

 



 

 

These are three views of shipwrecks, all in deeper water than divers can comfortably operate.

 

·         What technology was likely used, how does it work and why is that technology appropriate?  What does it tell us about the ship?

·         Note the coordinates are different in the three views.  Does that mean we have more than one shipwreck depicted?  Why or why not?  What is different in the three views?


 

This map shows a search for a lost object in the ocean. 

 

Can you tell what kind of sensor was deployed just from the search pattern? What do you think might have been used (give at least two examples), and which do you think is more likely?   Insure that you discuss the major features you see, and include appropriate terminology.

 


 

 

 

This map shows a calculated drift for a ship, with three different motions modeled in different colors and a resultant in red.  Discuss what you think the motions might be, and what color might go with each.  Which motion is most important, and which least important, to determine a search area, and why do you say that?

 

 


 

 

 

The map above shows the routes on a Dutch ship on 3˝ round trips between Amsterdam and the Dutch colonies in what is now Indonesia during the 1840’s, using purple symbols.     

·         One map shows wind vectors in January, and the other for August.  Which map is which, and how could you tell?

·         Highlight the route used to go to the Indies, and indicate why they used that route.

·         Which segment of the route do you think provided the biggest challenges for them?  What in the wind patterns supports this, and do the recorded positions almost match your conclusion?

·         In evaluating the positions recorded in the logbooks and shown on the maps, do you think there is any difference in the accuracy of the latitudes and the longitudes?  Why do you think this?

·         If this had been British ships going to India instead of Indonesia, do you think they would have followed the same or different routes?  Why or why not?

·         Tom Hanks starred in Captain Phillips, about an act of piracy that took place in April 2009 in the NW Indian Ocean.  Does the seasonality depicted in these maps affect 21st century piracy?

 

Insure you answered 4 of the 5 diagrams.