Stereonets
1. Plot the orientations of the following stretching lineations, and determine their plunge and plunge direction:
a. pitches 06° N on 351 °/37° E b. pitches 79° W on 285°/62° N c. pitches 42° N on 358°/86°E Also, plot the poles to the above planes on your stereonet.
2. Two fractures have the following orientations: 067°/38° SE, and 291 °/76° SW.
What is the plunge and plunge direction of the intersection of the two fractures?
What is the angle between the two fractures?
3. Along a vertical railway cutting, a bed has an apparent dip of 20° to 298°. If the bed strikes 067°, what is the true dip and dip direction?
4. In a mine, a tabular dyke has an apparent dip of 14° to 270° in one tunnel and 25° to 169° in another tunnel. What is the true strike and dip of the dyke?
5. Plot the planes of the limbs of an antiformal fold dipping at 50N/101 and 605/065.
The point where the two planes intersect indicates the plunge of the fold. What is it?
6. Plot the poles to bedding of the following dip and strike data collected across a fold.
72SE/228 56SE/238 365/270 325/293 35SW/340 46W/003 62W/018 79NW/030
Draw the best-fit great circle that intersects these points, and the pole to this great circle. This pole gives the amount and direction of plunge for this fold. What is this value?
