Using the principles of stratigraphy, what sequence of events can be inferred from this cross-section? Start with the oldest event and work forward, referring to the various sedimentary layers and the fault by letter. State which principle you are using to establish each interpretation. For example, “B is the oldest layer (principle of superposition), followed by….” Using the principles of stratigraphy, what sequence of events can be inferred from this cross-section? Start with the oldest event and work forward, referring to the two igneous intrusions and the surrounding country rock by letter. State which principle you are using to establish each interpretation. Now it gets a bit trickier, but just work through it step-by-step. Again using the principles of stratigraphy, what sequence of events can be inferred from this cross-section? Start with the oldest event and work forward, including all of the lettered features. State which principle you are using to establish each interpretation. Now to combine the stratigraphy with the other aspects of the geology. Derive and explain the history of this hypothetical region from the oldest preserved events to the youngest. Include everything which can be inferred from the drawing, including a reasonable interpretation of the likely rock types. To get you started, assume the lowest rocks (the pervasively folded material) are metamorphic. Their protolith can’t be determined from this sketch, so you don’t need to work any farther back in time than “Some sort of rock was buried deeply enough to be metamorphosed, then next….” For this one, you should certainly be using the principles of stratigraphy but you don’t need to state which principles you used for each step. Just tell the geologic story.