Techniques used to establish relative dating
This relative time scale divides the vast amount of earth history into various sections based on geological events (sea encroachments, mountain-building, and depositional events), and notable biological events (appearance, relative abundance, or extinction of certain life forms).
Objectives: When you complete this activity, you will be able to: (1) sequence information using items which overlap specific sets; (2) relate sequencing to the Law of Superposition; and (3) show how fossils can be used to give relative dates to rock layers.
INTRODUCTION Scientists have good evidence that the earth is very old, approximately four and one-half billion years old.
Scientific measurements such as radiometric dating use the natural radioactivity of certain elements found in rocks to help determine their age.
These major concepts are part of the Denver Earth Science Project's "Paleontology and Dinosaurs" module written for students in grades 7-10.
The complete "Paleontology and Dinosaurs" module takes approximately four weeks to teach. " activity is a 30-minute introduction to geologic time.
The study of fossils and the exploration of what they tell scientists about past climates and environments on Earth can be an interesting study for students of all ages.
Teaching about Earth's history is a challenge for all teachers.
This would also mean that fossils found in the deepest layer of rocks in an area would represent the oldest forms of life in that particular rock formation.
In reading earth history, these layers would be "read" from bottom to top or oldest to most recent.