by Betty Carew

Created on: April 08, 2009

The process of fossilization is not an easy one and there are several different ways that this process takes place. Some of these methods that form fossils are extremely rare. A fossil can be as large as the dinosaurs that once roamed our planet or as small as a micro organism but the process are the same. These include freezing, drying, asphalt, amber, carbonization and permineralization. To understand how each of these work we need to look a little deeper into how fossils are formed.

Millions of fossils have been found all you have to do is look into some of the museums that dot our cities. University paleontologist labs and fossil dealers hold many specimens, not including private collectors but even with all of these; it only comes to a fraction of the life that inhabited out earth throughout time.

The first step of fossil formation is that something must die such as plant, insect or animal to accomplish this. It must die near water or fall in water shortly after its demise. The water acts as insulation against any elements that would otherwise contribute to its decomposition. For example if a trilobite dies of old age at sea bottom, bacteria takes care of the soft parts of the body but leaves the exoskeleton intact. Soon sediments cover up the skeleton that remains. This has to happen rapidly in order to achieve fossilization.

There are other effects that can help to fossilize, such as landslides and mud slides. River deltas are also great for quick accumulation of sediment. If a trilobite dies and is covered in any of these, the fossil formation is started. Sediment has a very big influence on how well the fossil will turn out, if the sediment is fine and grainy something like clay, it allows for more detail but course sediment like sand shows less. The chemical of the sediment also has an influence on the fossil, for example, if there is a lot of iron in it, the rock will be red while phosphates will darken the rock to gray or black. So much depends on nature while the fossil is being created.

As time passes sediment will keep piling on the fossil and will compact the layers under it due to the sheer weight, this is what eventually, turns the sediment to rock. If it happens that water can seep down through the rock to reach the fossil it would be even better. Some of the minerals stick to the sediment forming a sort of glue to hold everything together. Ultimately after millions of years the trilobite is totally dissolved leaving a perfect imprint in the

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