GEOL360 Structural Geology Name______________________ Date_______________________ Problem Set #3: Apparent Dip, Angles and Orientations Part 1. Apparent dip 1. In a mine, a tabular dike has an apparent dip of 14°, 270° in one tunnel and 25°, 169° in another tunnel (here we use azimuth directions). Using a stereonet, what is the attitude (strike and dip) of the dike? _____________________ 1. Along a vertical railroad cut a bed has an apparent dip of 20°, N62°W. The bed strikes N67°E. What is the true dip? _____________________ 1. Suppose a fault strikes N10°E and its apparent dip trends S26°E and plunges 35°. Using a stereonet, determine the true dip of the fault. _____________________ Part II. Angle between two lines 1. What is the angle between the following two lines? a. 35°, S10°E a. 15°, N23°W _____________________ 1. What is the angle between the following two lines? a. 12°, N8°E a. 40°, S19°W _____________________ 1. What is the angle between the following two lines? a. 70°, S38°E a. 49°, N15°E _____________________ Part III. Angle between two planes 1. What is the angle between the following two planes? a. N27°E, 85°SE a. N89°W, 7°NE _____________________ 2. What is the angle between the following two planes? a. 315°, 20°NE a. 165°, 24°SW _____________________ 3. What is the angle between the following two planes? a. 014°, 10°SE a. N18°W, 37°NE _____________________ Part IV. Orientation of the intersection of two planes: 1. Determine the orientation of the intersection of the following two planes: a. N70°E, 80°SE a. N15°W, 35°NE _____________________ 2. What is the orientation of the intersection of the following two planes? a. 170°, 19°SW a. 265°, 55°NW _____________________ 3. What is the orientation of the intersection of the following two planes? a. 065°, 45°NW a. 310°, 28°NE _____________________ Part V. Orientation of a line within a plane (e.g., rake): 1. While in the field you measure striations that rake 60°SW along a fault that trends N35°W, 18°SW. What is the orientation of the striations? _____________________ 2. While in the field you measure striations that rake 25°SW along a fault that trends N28°E, 50°SE. What is the orientation of the striations? _____________________ 3. In the field you measure mineral lineations that rake 70°NE in a quartzite bed that trends 345°, 56°NE. What is the orientation of the mineral lineations? _____________________ 4. In the field you measure stetched belemnites that rake 45°NW in a limestone bed that trends 215°, 30°NW. What is the orientation of the belemnites? _____________________.