ES304 Self-assessment Test 1

The questions in this test are similar to those in the end-of-semester assessment. However, the actual assessment will have few multiple-choice questions, and many single-word answer questions compared with this version. A sample paper will be posted later in the semester.

If you have difficulties with any of the answers, don't hesitate to see or email me.

In each section, either choose answers with the radio buttons, or from the pulldown menus, then press the "submit" button to have the test scored and to get some feedback. At this time there is no record of your performance retained on the system.

 

Test 1

Test 2

Test 3

Test 4

Questions about rock and mineral properties will usually be one-word-answer style in the final paper:

Question:

What unusual physical property does the rock material possess?

 Density Magnetism Electrical Conductivity Elasticity Radioactivity
1 pyrite
2 chert
3 muscovite
4 komatiite
5 basalt
 

 

Test 2

The choices in some of these menus may sometimes seem strange or unlikely—but most of them have been served up as answers in exams, so don't scoff too loudly!

 

1
 What is the primary reason for variations in gravity observed at the Earth's surface?  
2
 What other information is needed to make a Bouguer Anomaly map, besides gravity observations? (Choose the one you think most important.)  
3
 What factors control the maximum amplitude or magnitude of the gravity anomaly due to a spherical source?  
4
 What is the geometric relationship between a level surface and the gravity force?  
5
 What, roughly, is the size of a "geological" gravity anomaly, in metres per second per second?  
6
 The deeper of two linear gravity anomalies, which both have roughly the same amplitude, will be the one which is...  
 
 

 

Test 3

Don't forget to recheck any of the answers which you don't agree with. First go to the notes, the web pages, and/or a textbook; if you still don't follow, email or see me.

 

1
 How does the gravitational attraction due to a point mass vary with distance from the mass?  
2
 Host rocks have a SG of 2.2, and you use a SG of 2.7 in modelling an intrusion as 4 m in width at 10 m depth. If drilling shows the intrusion density to be 2.5, what would you revise the thickness to?  
3
 Gravity mapping shows an isolated positive anomaly, roughly circular, peaking at 44 gu. The background level, away from the anomaly, is about 20 gu. The diameter of the anomaly at 32 gu is 550 m. What is the approximate depth to the centre of the anomaly?  
4
 Gravity decreases by about 3 gu per metre in elevation. A gravimeter on a reservoir wall would change by how much, if the wall sinks by 1 mm as the dam fills?  
5
 A gravimeter is placed in a borehole which passes vertically through a sedimentary layer saturated with gas (low density). After correcting for the elevation factor, how would relative gravity vary with depth near the gas sand?  
6
 If gravity on the Moon is 1/6 of gravity on Earth, why didn't the astronauts fall off (and back to Earth)?