STEREOGRAPHIC PROJECTION
 
 

Stereonets have a variety of uses, from crystallography to earthquake studies and plate tectonics as well as Structural Geology. Over the course of your studies you will use them again and again.

1) LINES

Represent the following lines on a stereographic net:
 
 

S52E/45, N79E/09, S88E/22, S2W/48, S41W/32, S58W/16, S68W/03
 
 

2) PLANES
 
 

On a stereographic net, draw the poles to the following planes. Place a number next to the poles.
 
 

(1) N72E/50 S, (2) S21E/81W, (3) N2E/68W, (4) N38E/45NW, (5) S88E/42N, (6) S49E/59N, (7) S32E/74NE, (8) S21E/87E
 
 

Verify the results to the above questions by overlaying both sets of answers. Note that (1) all the lines in exercise 1 should be contained in the plane N72E/50S, and 2) the poles of the planes in exercise 2 coincide with the trace of each of the lines in exercise 1.
 
 

3) PLANES and LINES
 
 

Construct the plane which contains the following two lines:
 
 

P1 a: N55E/32 b: S35W/50

 P2 c: N44E/32 d: S40E/64

 P3 e: N81E/54 f: S11E/25

 P4 g: N43W/45 h: S87E/17

 P5 i: N46E/49 j: S57E/29
 
 

Which plane contains the poles to planes P1 through P5? Draw the pole to this plane.
 
 

3A) TRUE DIPS FROM APPARENT DIPS
 
 

Find the strike and true dip of a plane, given two apparent dips for all the examples seen in Lab 3.1.
 
 

4) LINES GIVEN A PITCH
 
 

Draw the following lines, given the pitch on a plane:
 
 

N40E/60SE, 40NE

 S10E/48E 32 N

 S48E/55 NE , 28 SE

 S84E/78N, 32 E
 
 

Verify that the poles of the planes lie on one plane and that the plotted lines are contained on another plane. What are the azimuths of these lines?
 
 

5) INTERSECTION OF TWO PLANES
 
 

Given the following planes (P):

P1: N58E/66E,

P2: S36E/36 NE,

P3: N70E/30W,

P4: N10E/60W

find the intersection (l) of these planes:
 
 

l1 = P1 and P2

 l2 = P3 and P4

 l3 = P1 and P3

 l4 = P1and P4
 
 

6) ANGLE BETWEEN TWO PLANES (OR TWO POLES OF A PLANE)
 
 

Measure the angles between two planes P1 and P2; P1 and P3; P1 and P4 whose azimuths were given in the previous question.

 Verify that the angles between th following are right angles: pole of P1 and l1; pole of P3 and l3;

 pole of P4 and l4
 
 

7) PROJECTION OF A LINE ON TO A PLANE
 
 

Project line L:S80W/41 on to the following planes:
 
 

P1: N50/60SE

 P2: N25/60W

 P3: S70E/75N

 P4: S20E/70E
 
 

8) PERPENDICULAR PLANES WITH A GIVEN DIRECTION

Trace planes (M0- M8) at right angles to the following planes and which pass through the line in the plane, given by its pitch:

 N44E/68 E, 34 SE

S48E/28 NE, 40 NW

 S36E/20 SW, 00

 N8E/12 E, 70 S

 E/60 S, 22W

 N5E/55 E, 72 S

 S2E/55 E, 72 S

 S54E/81 SW, 46SE

 S60E/70E, 48NE
 
 

Make sure that the poles of planes M0 thorugh M8 lie on a great circle whose pole is the intersection of these planes (see exercise 5)