PART 1A: Relative Age Dating (8 Points) FIGURE 1a: The diagram is a cross-section showing the geology, in profile, of a region [W = west; E = east). Rock types and contacts between rock unitsare identified in the Legend. LEGEND – Sedimentary rocks: Ss (a, b and c) = sandstone, Cg = conglomerate, Sh (a and b) = shale, Slt = siltstone, Lm (a and b) = limestone; Igneous rocks: extrusive: B – basalt, V–andesite, intrusive: Di – diorite, Gr – granite; Metamorphic rock:M– schist. Two unconformable boundaries: X and Y (darker lines). 1.a) Use the principles of relative dating to determine the geologic history of the area shown in the diagram. No rock layers have undergone