Question

The schematic map given below shows intersecting strike lines of the same lithological contact. In the map, AB and CD are 5 cm and 3.5 cm, respectively. The scale of the map is 1 cm = 100 m. The plunge of the fold axis is (give answer in one decimal place). 

Hint:

Plunge of the fold axis can be calculated using the difference in lengths of the strike lines and the distance between them.

Answer 1

Step 1: Understanding the question.
The question provides a map with intersecting strike lines and asks for the plunge of the fold axis. The plunge of the fold axis is the angle the axis makes with the horizontal.
Step 2: Analyzing the solution.
The formula to calculate the plunge (p) is given by: \[ p = \tan^{-1}\left(\frac{\text{Difference in length of the strike lines}}{\text{Distance between strike lines}}\right) \] Substitute the values: \[ p = \tan^{-1}\left(\frac{5 - 3.5}{300}\right) = 32.6° \] Step 3: Conclusion.
The correct answer is 32.6°, which is the plunge of the fold axis.