4 Fill in the gaps with the missing words.

A fault is a (1) _______________ along which one side has moved (2)_____________ to the other. The term fault is generally used for (3)___________ fractures. A fault divides a rock into two (4)________________. The bottom surface of the upper block is the (5)____________, and the top surface is the (6)_________________. Faults are classified in terms of the (7)_________________ of the fault surface. The fault dip may be more than (8)_______________, which is called (9)______________. If it is less than (10) __________, it is a (11)____________. A fault can be divided depending on the (12)___________ of the (13)__________. Also they are subdivided on terms of (14) ____________. Faults may also be either (15) ________ ( ) or (16)___________ ( ).

5 Read the following fault types. The look at the diagrams and then try to draw them by heart. And draw a diagram. (r.P – 8.3.1.3, 8.3.1.4)

1. Normal fault – stretching breaks rocks along

a steep fault plane, and one block drops or rises

against the other.

2. Reverse fault – compression forces one block

up and over another. A thrust fault is a reverse fault

with a low-angled fault plane producing great

horizontal movement.

3. Tear (strike-slip, transcurrent, wrench) fault –

horizontal shearing along a vertical fault plane.

Transform faults are tear faults at right angles

to oceanic ridges.

4. Graben- a long, narrow block sunk between

two parallel faults.

5. Horst- a horizontal block raised between

two normal faults

Fig. 52. Fault types

6. Here are six definitions. Read the definition, then name the term and give its translation (r.P – 8.3.1.3, 8.3.1.4)

1. horizontal block raised between two normal faults

2. a long, narrow block sunk between two parallel faults

3. one block drops / rises against the other

4. horizontal shearing along a vertical fault plane

5. an uplifted, tilted block

6. one block is forced up and over another

3.1.4 Listening comprehension

You will hear part of a lecture. For statements 1-14, give the correct answer according to what the speaker says. You will need to write a word or short phrase.

1. What is another term for splits formed in stressed rocks?

2. What is a joint?

3. How do joints form?

4. Where do joints occur?

5. What are faults?

6. What explains the weakness in the Earth’s crust?

7. What does block faulting create?

8. How many types of faults are there?

9. What are the main types of faults?

10. When does a normal fault occur?

11. How is a reverse fault formed?

12. What forces create reverse faults?

13. What is an example of a tear fault?

14. What is the difference between graben and horst?

3.2 Comprehension: folds

3.2.1 Vocabulary

fold	складка;
folding	складкообразование; складчатость;
compression	сжатие, сдавливание;
drape	собирать в складки;
compaction	уплотнение;
anticline	антиклиналь;
syncline	синклиналь;
convex (convexity)	выпуклый (выпуклость);
concave (concavity)	вогнутый (вогнутость);
trough	впадина, мульда;
curvature	кривизна, линия изгиба;
hinge point	точка шарнира;
locus	местоположение;
hinge surface	осевая плоскость;
inflection point	точка перегиба;
limb (flank)	крыло;
thrusting	образование надвигов;
basement block	основание.