WARM-UP 85 The difference between relative dating and absolute dating is that relative dating is a method of sequencing events in the order in which they happened. Absolute dating is a method of estimating the age of a rock sample in years via radiometric techniques.

Eons to Eras to Periods To Epochs WARM-UP # 86 Fill in greater > or less than to compare the geologic time units Eons to Eras to Periods To Epochs Periods > Epochs Eras > Periods Epochs < Eons Eons > Periods Eras > Epochs Eras < Eons

WARM-UP # 87 1. Cast fossil 2. Mold fossil 3. Petrified fossil A. When minerals replace all or part of an organisms tissues, such as bone or wood. B. The trace or remains of an organism that lived long ago, most commonly preserved in sedimentary rock. C. When animals are preserved in or close to their natural state as in amber, tar, or ice. D. An impression or imprint of an organism in sediment which turns to rock. E. A fossil that is used to establish the age of a rock layer F. Formed when sediment fills an impression made by an organism and becomes rock. G. Thin layer of carbon from the organism left behind in the rock. 1. Cast fossil F 2. Mold fossil D 3. Petrified fossil A 4. Preserved remains C 5. Carbon films G 6. Fossil B 7. Index fossil E

Warm-Up # 88 1. Superposition 2. Absolute dating 3. Relative dating C 2. Absolute dating B 3. Relative dating A 4. Geologic column D A. Finding if a rock layer is older or younger than the layers around it. B. Finding the exact age of an object using unstable atoms C. The idea that younger rock lies above older rock. D. Detailed series of rock layers of all known fossils and rock formations from around the world.

Warm-Up # 89 1. Explain the four features of an index fossil. Found worldwide Abundant Easily recognizable Alive for only a short period of geologic time