Cross Section 4: The complicated one! Several unconformitics, meaning multiple episodes of uplift and erosion; a couple episodes of deformation; an intrusion; faulting: this one has it all! Youngest rock unit: Oldest rock unit: Summary of geelogic history (HINT: I count at least nine separate events or episodes): Do not forget the necessity of uplift and erosion every time an angular unconformity appears Describe the locations of the two angular unconformities by the rock units on either side. List the units cut by the fault. Which side of the fault moved up or down relative to the other side of the fault? Tough question: There is a third, less obvious unconformity in this sequence. Can you find it? (Look at the rock types next to each other, and think about how they are formed or deposited.) .