These foreign bodies are picked up as magma or lava flows, and are incorporated, later to cool in the matrix.
Teaching Introductory Geoscience Courses in the 21st Century.
Student Prerequisites None Activity Procedures 1.
Three-lobed body; burrowing, crawling, and swimming forms; extinct.
Description: Scientists use special tools to find the absolute, number of years ago a given rock layer was formed. Place a number beside each event according to which happened longest ago 1 and which happened most recently 10 c.