Home >> Science & Nature >> Nature

How to Identify Fossils Found in Rivers

Fossils are the mineralized remnants of dead creatures. Chemical, biological and physical forces combine to convert the materials of a living creature into stone. The perfect combination of circumstances does not occur very often, but because animals have been around for hundreds of millions of years, there have been many opportunities for the right circumstances to come together. Keep in mind that what is desert, mountain or river today was probably completely different when the fossil was formed.

Instructions

- 1
  Identify the current geological structure of the site where you found the fossil. Note evidence of geologic upheaval and erosion sites. For example, a river is a site of potential erosion.
- 2
  Estimate the geological strata that contains your fossil. By observing characteristics of the geologic layers where you made your discovery and by noting features of the layer itself, you can fit your sample into the right spot in the geological column.
- 3
  
  Ammonites are among the most common fossils found.
  
  Measure your fossil. Note the overall measurements and the measurements of any distinctive features, such as leaf size or shell spirals.
- 4
  Note any symmetry of the fossil. Is the left side the same as the right? If so, then it has bilateral symmetry. If the fossil appears roughly circular, with features that repeat at a certain distance from the center, then it has radial symmetry.
- 5
  
  Most fossils were created in marine environments as layers of sediment were deposited.
  
  Combine the age, size and features of your fossil with fossils that have already been categorized, and see where it fits in. There are online resources available to help with the comparison, in addition to written catalogs.

Nature