110 likes | 288 Views
814. Compare fossils found in sedimentary rock to determine their relative age. Compare fossils found in sedimentary rock to determine their relative age. Compare fossils found in sedimentary rock to determine their relative age.
E N D
814 Compare fossils found in sedimentary rock to determine their relative age.
Compare fossils found in sedimentary rock to determine their relative age.
Compare fossils found in sedimentary rock to determine their relative age.
Compare fossils found in sedimentary rock to determine their relative age. • Fossils • Fossils – the preserved remains or traces of once living organisms • Remains – any part of the organism is a fossil a. example; bones, teeth, horns, even soft tissue 2. Traces - any imprint, footprint, tooth mark, tail mark, scratch mark a. not part of the actual animal but evidence the animal has been there
Compare fossils found in sedimentary rock to determine their relative age. II. Dating fossils • Absolute dating – the exact age in years that a fossil has existed • Example; 25,000 years or 65 million years • Relative dating – a comparison of the ages of different fossils • only tells which is older or younger not a specific number of years
Compare fossils found in sedimentary rock to determine their relative age. III. Fossil formation • Steps of fossil formation • The organism dies • the remains are rapidly buried in sediment • over time the sediment that covers the organism is compacted and cemented to become sedimentary rock • The layers of sedimentary rock above the remains eventually erode and the fossil is exposed
Compare fossils found in sedimentary rock to determine their relative age. IV. Superposition • Superposition – the rock layers nearer to the surface are younger than deeper rock layers • “younger over older” • Since the more shallow layers of rock are younger than deeper layers of rock, then the fossils found in more shallow rock layers are younger than the fossils found in the deeper layers of rock. • This allows you and scientists to tell which fossils and thus which animals lived first, next, and so on.
Compare fossils found in sedimentary rock to determine their relative age.
Compare fossils found in sedimentary rock to determine their relative age.
Compare fossils found in sedimentary rock to determine their relative age.