Fezouata Formation facts for kids

The Fezouata formations in Morocco are amazing rock layers from a very ancient time, called the Lower Ordovician period. This was about 485 to 470 million years ago! These formations are like a super-old photo album, holding fossils of creatures that lived in the sea.

Scientists once thought many of these creatures had completely disappeared much earlier, during the mid-Cambrian period. But the fossils found in the Fezouata formations prove that these ancient sea animals actually lived for much longer than expected. It's like finding a living dinosaur when everyone thought they were all gone!

What Kind of Life Lived There?

More than 1,500 types of soft-bodied creatures have been found in the Fezouata formations. These are similar to fossils found in another famous site called the Burgess Shale. About 50 different kinds of animals have been identified! There are also some creatures with shells, but they are not as common.

The types of animals found changed a lot over time as the rock layers built up. This means the sea environment was also changing. Scientists also found small burrows, which are tiny tunnels made by animals in the mud. However, there aren't many large burrows. This might mean there wasn't much oxygen in the water or mud back then.

Amazing Ancient Animals

Some of the most exciting finds include creatures called bryozoa and graptolites. These types of animals were not around during the Cambrian period, so finding them here is a big deal! Other fossils, like different kinds of echinoderms (related to starfish), show that the ocean water had normal salt levels. The shelled animals found here are also quite similar to what scientists expect to see in open Ordovician seas.

The soft-bodied fossils are especially cool because they show creatures that are usually hard to preserve. Many of these look like animals from the famous Burgess Shale. Plus, there are lots of other strange Ordovician creatures, including many cheloniellids and horseshoe crabs.

How Were These Fossils Made?

Where the Animals Lived and Died

The rocks with these fossils formed in calm, deep ocean waters. This area was usually far below where waves could stir up the sea floor. However, big storms or other strong events could have moved a lot of mud and sand very quickly. When this happened, animals living on the seafloor would get trapped and buried fast. This quick burial helped preserve their bodies as fossils. Because of this, most of the fossils found are of creatures that lived on or near the seafloor.

How Fossils Were Preserved

The fossils from the Fezouata formation are usually squashed flat, like they've been pressed in a giant book. But some still show a bit of their original 3D shape. Many of these fossils are covered with a fine layer of shiny pyrite (also known as "fool's gold") and tin. This type of preservation is very similar to what is seen at another famous fossil site in China called Chengjiang. Even soft parts of the animals, like their legs or antennae, are often preserved!

Where to Find Them

These amazing fossils are spread out over a huge area of 500 square kilometers (about 193 square miles). They are found in the Draa Valley in southeast Morocco, just north of a town called Zagora. The fossils are found throughout a thick column of rock, about 1.1 kilometers (0.7 miles) deep. This rock column covers the two earliest parts of the Ordovician period.

Discovery Story

The incredible fossil beds of the Fezouata formation were first discovered in the late 1990s. A local fossil collector named Ben Moula found some of these unique fossils. He then showed them to a PhD student who was working in the area at the time. This led to the scientific discovery of this amazing fossil site!

Images for kids

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  This map shows what the Earth looked like during the Middle Ordovician period, about 460 million years ago.