Tar is thick and sticky The La Brea tar pit in Los Angeles, California is famous for its many fossils!
Types of Fossils Replaced Remains : Hard parts of plants or animals are replaced by minerals over time. The minerals are in the shape of the organism. –This occurs when water containing minerals seeps through the plant/animal material. –Petrified wood forms in this way
Example: Petrified Wood Minerals have replaced all of the wood cells and turned this wood into rock!
Types of Fossils Molds and Casts: Impressions and copies Molds are created as mud or sediment becomes rock around dead organisms. Casts are created as minerals get deposited into the molds and then harden. They make a copy of the fossil. Ice cube tray= Mold Ice= Cast