Look under the sea at Australia's Great Barrier Reef! This is one place where organic sedimentary rocks are being made.
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Courtesy of Abi Howe, American Geological Institute
Some Sedimentary Rocks Are Made of Fossils!
Rocks made of fossils are called organic sedimentary rocks.
This picture shows one place where organic rocks are being made on the Earth today. This is a coral reef where the skeletons of coral, clams, fish, and algae are being bound together to make a rock called limestone.
Some organic rocks are made of plants! They form when plant that have died are squashed deep underground for millions of years. The rock that they make is called coal. Coal doesn’t look like it is made of sediment. It is also often difficult to see the plant fossils within it because they have become so packed together.
Last modified August 25, 2003 by Lisa Gardiner.
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