Describe the two principles that explain how fossils form

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. preservation of original remains, permineralization, molds and casts, replacement, and compression.

Explanation:

Two Principles to explain how fossils form are Permineralization and molds and casts

What are Fossils?

Fossils are defined as trace remains of organisms. and the process when these fossils are preserved in a hard form is known as Fossilization.

The principles that explain the formation of fossils are

Permineralization occurs when water rich in mineral  from rocks seep into spaces of decayed and dead plant or animal,This  leaves deposits of minerals behind which creates  a cast of the organism over time.

Molds and casts occurs when sediments from rocks fill impressions created by an organism's body part eg bones. they slowly form a fossil in the actual shape of the animal bones over time.

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