Superposition and Fossils

Observation Inference

Absolute Aging Gives a number

Relative Aging Compares objects (older, younger)

Relative Aging – which is oldest?

Law of Superposition

Law of Superposition Older rocks on bottom; younger rocks on top

What is a fossil? Remains of organisms that lived in the past

Where do we find fossils? Sedimentary Rock

What can fossils tell us? Climates and environmental conditions in the past Tropical fossil found in Antarctica Aquatic fossil found in desert Area was once a warm climate Area was once underwater

Index Fossils Tells us the AGE of a rock layer An organism that lived in only ONE geologic time period

Do You Know? The difference between ABSOLUTE & RELATIVE aging? What the Law of Superposition is? What the Law of Superposition tells us about the relative age of rock layers and fossils? Where we find most fossils (what type of rock)? What fossils can tell us about the past? What an index fossil is? What an index fossil can tell us?