Rocks and Fossils

The remains of organisms from millions of  years ago are preserved as fossils in sedimentary rocks

Fossils are formed in one of two ways:

1) Organism decomposes, and minerals become implanted in the tissue so that the organism turns to rock

2) Organism’s shape leaves an impression in the ground

Fossils are formed in areas of insufficient oxygen to decay, in low temperatures (glaciers) and high soil acidity (peat bog)