ChronoZoom more info ChronoZoom is a free, open source interactive timeline tool for learning about all kinds of history, stretching back all Users can seamlessly scroll through different parts of history and zoom in for more detail and related resources. Graphical Representation of Geologic Time more info An illustration of the 4. Observe an animation showing growth of a continent.
Relative dating is the science of determining the relative order of past events i. In geology, rock or superficial deposits , fossils and lithologies can be used to correlate one stratigraphic column with another. Prior to the discovery of radiometric dating in the early 20th century, which provided a means of absolute dating , archaeologists and geologists used relative dating to determine ages of materials. Though relative dating can only determine the sequential order in which a series of events occurred, not when they occurred, it remains a useful technique. Relative dating by biostratigraphy is the preferred method in paleontology and is, in some respects, more accurate.
The links below are animations illustrating the principles of relative dating determining the sequence of events and to images of real examples on which to try out the principles. To return to this page, click your Back button. Click on each of the five small images below to bring up an animation about the seas moving in and out. Click and drag sideways to move the seas in and out, and drag up and down to see what's beneath the water.