Historic Shipwrecks Spring 2015

Exam 1 Gold

 

 

Definitions

6 @ 5 points

30

 

Short answer

4 @ 10 points

40

 

Diagrams

3 @ 10 points

30

 

Total

 

100

 

 

No Authorized references.

 

 

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 6 of the 11 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.

 

·         Crossover:

·         Curie temperature:

·         Fluyt:

·         Geoid:

·         Induced versus remnant magnetization:

·         Layback:

·         Lidar:

·         Mowing the lawn:

·         Slant range:

·         TWTT:

·         Wet monsoon:

 

Insure that you only answered 6 definitions.



Short answer.  You must answer 4 of the 6 questions

 

In the age of sail, how did ships determine latitude and longitude, and why did logbook entries end at noon?

 

 

 

Before about World War II, what two methods were used to map depths in the ocean, and why are they no longer used for serious mapping?

 

 

 

What method still provides the “best” depth estimates in most of the world’s oceans (such as the Indian Ocean where MH370 crashed) and what better and more costly method is being used to acquire better data there?   Explain the tradeoffs which influence which method is used to collect data.


Consider a magnetometer:

·         What does it measure?

·         What are you looking for with it?

·         Do you want to operate it close to the surface or close to the bottom?  Why?

 

 

 

We discussed two ways to introduce uncertainty in to modeling a ship’s drift: picking extreme likely end members, and adding random errors with Monte Carlo modeling.  How do these vary, and how can they help plan a search?

 

 

  

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

 

 



 

 

These are two views of a shipwreck found in 125 m of water.

 

·         What technology was likely used, and why is that technology appropriate?

·         Note the x-coordinates are different in the two views (y is also different).  Why would we change the coordinate system, and does it make any difference in how we interpret the view?

 

 

 

The diagram above (Omitted for copyright reasons) shows the search area for a sailboat and a lifeboat.  What forces operate on the two, and why do they respond differently?  How would you use this result in looking for a vessel like the BHR?

 


 

 

The map above shows the Indian Ocean in January and July, with the climatology for the winds.

·         Which map is which, and how could you tell?

·         If you were looking a shipwreck with Chinese porcelain, shipped from Indonesia and India, where you look and why?

·         If you were looking for a shipwreck with the European trade goods begin taken to China, where would you look and why?

·         Is there anywhere in the Indian Ocean away from the destination ports that might have shipwrecks with both types of goods?  Why?