The Elements of Geology

by William Harmon Norton

Fig. 193

1. A normal fault with a hade of 15°, the original fault scarp remaining.

2. A normal fault with a hade of 50°, the original fault scarp worn away, showing cliffs caused by harder strata on the downthrow side.

3. A thrust fault with a hade of 30°, showing cliffs due to harder strata outcropping on the downthrow.

4. A thrust fault with a hade of 80°, with surface baseleveled.

5. In a region of normal faults a coal mine is being worked along the seam of coal AB ([Fig. 193]). At B it is found broken by a fault f which hades toward A. To find the seam again, should you advise tunneling up or down from B?

6. In a vertical shaft of a coal mine the same bed of coal is pierced twice at different levels because of a fault. Draw a diagram to show whether the fault is normal or a thrust.