Fault surfaces sometimes contain overprinted slip lineations (fault striae). Such slip lineations can be used to determine the orientation of slip on a fault, and, therefore, whether the motion on the fault was strike-slip, dipslip, or oblique-slip. A geology student who was just learning to use a Brunton compass recorded the orientations of five slip lineations on one fault surface. The strike and dip of the fault surface is 320°, 47°NE. The student’s five recorded lineation orientations are recorded in the table below.

Determine which lineation orientations are feasible and which ones must represent a mistake on the part of the student because the given orientation does not lie within the fault plane. Give a brief explanation for each of your five answers. For the valid lineation orientations, indicate which type of fault motion is indicated.

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Lineation (plunge and trend) a) 34°, due north b) 0°, 140° c) 33°, N66°W d) 47°, 050° e) 75°, due north Feasible? (yes or no) Explanation Type of motion indicated (strike-slip, dip-slip, or oblique-slip)