Chapter 15, Problem 15STP

Summary Introduction

To describe:

The process illustrated in the given figure

Introduction:

A fossil is any preserved evidence of an organism. Plants, animals and even bacteria can form fossils. More than 99 percent of the species that existed have become extinct. Only a small percentage of these organisms are preserved as fossils. There are six categories of fossils; trace, molds, replacement, petrified, amber and mummies.

Answer to Problem 15STP

The processes involved in the formation of fossils include:

1. Organism dies and get buried in sediments.
2. Sediments build up in layers.
3. Minerals replace or fill in the pore spaces of bones and other hard parts of the organism.
4. Erosion exposes the fossils.

Explanation of Solution

The following figure illustrates the process of fossil formation.

The processes involved in the formation of fossils include:

1. After the death of the organism, the sediments deposit on the dead remains till the entire organism is covered completely by the sediments.
2. Sediments build up in layers eventually encasing the remains in sedimentary rock.
3. Minerals replace the organic matter or fill in the empty pore spaces of bones and other hard parts of the organism. In some cases the organism decays leaving behind an impression of the body.
4. The sediments harden into a rock. Erosion exposes the fossils.