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In Which Environments Are Fossils Found?

Fossils turn the imagination into a time machine, connecting people through visual imprints to life that thrived millions of years ago. Gazing at a fern print in a piece of coal or a trilobite shell in a piece of limestone, you can almost see the fern trembling in the primeval breeze or the trilobite scuttling across the sandy floor of an ancient ocean. Fossils can be found almost anywhere, if you know how to look.

Not Your Environment, But Theirs
- Fossils are not restricted by modern environments. Fossils have been deposited for as long as 3.5 billion years on Earth. They exist from every era. Fossils originated in innumerable kinds of terrain and climate throughout the ages. What fossils have in common across time is that something happened to preserve them in fossil form. The most common factor in the preservation of fossils was that the remains of an organism was quickly covered with loose material that later consolidated into rock.
Sedimentary Rock
- Loose material that consolidates into rock is called sedimentary rock. It begins as a sediment, like sand or river silt, then bonds over many years into a solid mass. The most common kinds of rock containing fossils are sandstone, shale and limestone. If you have little of any of these, you are unlikely to find fossils. Granite, marble and volcanic rock are usually not good bets for fossils.
Riverine Cutaways
- Because sedimentary rock forms in layers, a good way to look for sedimentary rock is where layers of rock are exposed and visible. One such place is a river bed. Water erodes the looser material, leaving the stone on the sides of the current exposed. You have probably seen these layers of rock from inside a creek bed or river bed. Using a rock hammer, you can chip away piece of that exposed rock and examine the pieces for fossils. Once you find one fossil, you are likely to find more since the conditions for that one fossil to be preserved probably preserved several of the life forms in that ancient environment.
Scoured Hills
- Another good environment for hunting fossils is high desert. Mountainous areas that are dry and have little vegetation are scoured by winds for long periods of time, leaving massive swaths of vertical ground exposed, with those corresponding rock layers. When you find a layer that contains fossils, you can often see that same layer matched for long distances around your location. You can simply follow that layer, chipping and inspecting as you go.

Rocks & Minerals