Structural Geology Problems
1. A vein outcrops at three points, A, B and C. B is 300 feet N20E of A, while C is 400 feet N80E of A.
B is 200 feet higher than A and C is 100 feet lower than A. Determine the strike and dip of the
vein using analytical methods.
2. In a stream bed, the base of a coal bed is exposed at an elevation of 1845 feet and the top of the
coal bed at 1632 feet. The horizontal distance between exposure is 2100 feet in the direction of
N33E. The dip of the coal bed is 42 degrees to the N5E. Find the thickness of the coal bed.
3. A vein strikes N-S and dips 35 degrees North.
Using analytical and graphical methods, determine the apparent dip in a N45E section. In what
direction would its apparent dip be at 25 degrees.
4. Determine the strike and dip of the bed given the following data:
a. 28 degrees to the S80W section
b. 37 degrees to the S20W section
5. The attitude of the sandstone units is N65E, 35SE. A horizontal traverse with a bearing of S10E
from the bottom to the top measured 125 meters. Find the thickness of the sandstone.
6. A vein strikes N90E and dips 35 to the south. What is its apparent dip in a N45E section. In what
direction would its apparent dip be at 75 degrees.
7. A vein that strikes N45W and dips 35 NE is exposed on the southwest side of a mountain range.
Its upper surface outcrops at an elevation of 1400 feet while its lower surface outcrops at 1200
feet. The slope distance between the outcrops measured perpendicular to its strike is 500 feet.
a. Find the thickness of the vein.
b. Calculate the depth to the top of the bed at a point 600 feet of where it outcrops, this
point is at an altitude of 1800 feet. On the same location, calculate the depth to the
bottom and of the bed and determine vertical thickness.
8. The top of the limestone bed with a thickness of 100 meters dips 30 degrees East as seen on
Point A, on a 30 degrees sloping ground surface. Since the bottom side of the bed is totally
covered, compute for the trace of the apparent thickness of the bed on the inclined ground
surface.
9. A vein strikes N45E and dips 35 degrees to the southwest. What is its apparent dip in a N90E
section. In what direction would its apparent dip be at 20 degrees.
10. A vein outcrops at three points, A, B and C. B is 300 meters N20E of A, while C is 400 meters
N80E of A. B is 200 meters higher than A and C is 100 meters lower than A. Determine the strike
and dip of the vein using graphical methods.
11. Given the following data:
Drillhole 1 has a collar elevation of 1000 meters
Drillhole 2 has a collar elevation of 1200 meters
Drillhole 3 has a collar elevation of 900 meters
Drilhole 2 is 500 meters N35W of drillhole 1 and drillhole 3 is 400 meters N75W of drillhole . the
top of the gold-bearing quartz vein was intersected at depths of 400 meters in drillhole 1,2 and
3. Find the strike and dip of the vein using analytical methods.