The principle of inclusions which states that the source of rock fragments found in a unit must be older than the unit with the fragments is important because . it showed that igneous rocks were younger than sedimentary rocks it provided a tool for sorting out the relative timing of various geologic events it provided a way to recognize if rocks had been deformed it allowed geologists to correlate rock units over large distances

15 points need quick 1. looking at your graph and the geologic time scale during what period did this rock form? what is the age span of the rock, in millions of years? 2. this rock sample is limestone and shale. with what you know about rock formation, what type of environment did these organisms live in? 3. if some of these fossil samples were found in a rock also containing leaf fossils, could you use radiocarbon dating to determine the age of this rock? explain.