Relative dating diagram
So we can infer that coal seam is younger than the faults (because it disrupts them), and of course the upper sandstone is youngest of all, because it lies on top of the coal seam.Exercise 8.1 Cross-Cutting Relationships The outcrop shown here (at Horseshoe Bay, B. Buff/pink felsic intrusive igneous rock present as somewhat irregular masses trending from lower right to upper left 2. A 50 cm wide light-grey felsic intrusive igneous dyke extending from the lower left to the middle right – offset in several places Using the principle of cross-cutting relationships outlined above, determine the relative ages of these three rock types.Archaeology for Amateurs: The Mysteries of Crete: Alliance for Lifelong Learning 2002.These pages are from a course designed for the Alliance for Lifelong Learning Web site, with an associated online discussion forum, and other functionality, and any references to these should be ignored.For example, a xenolith in an igneous rock or a clast in sedimentary rock must be older than the rock that includes it (Figure 8.6).Figure 8.6a A xenolith of diorite incorporated into a basalt lava flow, Mauna Kea volcano, Hawaii.The lava flow took place some time after the diorite cooled, was uplifted, and then eroded.(Hammerhead for scale) [SE]Figure 8.6b Rip-up clasts of shale embedded in Gabriola Formation sandstone, Gabriola Island, B. The pieces of shale were eroded as the sandstone was deposited, so the shale is older than the sandstone.
Layers 1-6 and Dike A eroded, forming the lower unconformity. In this session we will introduce you to the idea of relative and absolute dating, and explore the difference between these two ideas.Diagram 1 shows three sites, each with its own sequence of assemblages.Site 1 is the earliest, Site 2 is in the middle and Site 3 is the latest.So far, so good – but we still don’t have a way of pinning our relative sequence down in time.