A road-building company working in a seismically active area has contracted you to help trace the safest route for a new interstate highway. In the area shown on the map it is feared that old faults may still be active and may damage the new roads. Your task is to draw the fault on the map and describe its strike, dip and plunge of any fault lineations.

You have been asked by the company to carry out this job urgently because the bid for the road-building project is due in only a few days. The reason they are contracting you on such short notice is because the company lawyers have decided at the last minute to minimize liability by hiring an environmental geologist. Therefore, you are not able to go out to the field to map the fault at the surface and you are only able to work from a state geological map and a few well reports from lead mining companies that went bankrupt in the 1940's.

Here are your data:

1. The stratigraphic series consists of shales intercalated with thin (hint!) limestone beds all with constant regional strike and dip.

2. The mining report states that lead ore is found where a fault intersects the thin limestone beds.

3. Point A marks an abandoned lead mine pit where the fault cuts the limestone bed at the land surface. That is, A and the limestone are all exposed at the surface.

4. At point B (old drill site) the same limestone bed that was found at point A is now found at 300 m depth below the surface containing lead ore.

5. At point C (another old drill site) two limestone beds were found; one at 100 m depth, and the other at 300 m depth below the surface. The shallower bed is the lateral continuation of the bed drilled at point A but contains no lead ore. However, the deeper limestone bed contains lead ore.

Questions

What is the strike and dip of the limestone beds?

What is the strike and dip of the fault?

What is the plunge of the zones with lead ore?

What is the rake of the of the zones of lead ore on the fault surface

Draw the trace of the fault and limestone beds on the surface to show the road company the area they should avoid.
 
 

(Leave the following question for a future lab:

Plot the fault and beds stereographically and verify your results )