Fossils

By : Diya Wattal

What are Fossils

What are fossils : The remains of a prehistoric organism preserved in a petrified as a mold of cast rock .

What type of Rock are they found in ?

In certain conditions, and over a very long period of time, sediment becomes compacted and cemented into sedimentary rock. Fossils are more common in some kinds of sedimentary rocks than others. There are many factors that can contribute to the likelihood of an organism being preserved as a fossil. Fossils are most common in limestones. That is because most limestones consist partly or mostly of the shells of organisms. Sometimes, however, the shells are worn

How are they formed ?

Fossils are formed in a number of different ways, but most are formed when a plant or animal dies in a watery environment and is buried in mud and silt. Soft tissues quickly decompose leaving the hard bones or shells behind. Over time sediment builds over the top and hardens into rock.

Examples of how they are formed

One example is that a fly is going in a amber tree and gets stuck in the sap then eventually it will harden and turn into a fossil.