Name:__________________________________        Date:___________        Hr:________

Fossils of Minnesota

Purpose:

450 million years ago during the Ordovician time period, Minnesota was under 100-150 feet of salt water. This ancient ocean contained large amounts of sea plants and animals. These plants and animals then died, settled to the bottom of the ocean and formed thick layers of fossils in limestone and shale. Limestone and shale are types of sedimentary rock. Sedimentary rocks are formed by the deposition of material at the Earth's surface and within bodies of water. The other two types of rock are metamorphic and igneous rocks in which fossils cannot be found due to the tremendous heat and pressure that it takes to make igneous and metamorphic rocks. In this activity you are going to study and identify some of these Ordovician fossils trapped in a types of sedimentary rock, limestone.

Materials:

• Fossil Limestone sample
• Ordovician Fossil Identification Guide for Minnesota Limestone

Procedure:

1.        Pick out one of the limestone samples that contain a good variety of fossils.

2.        You must identify three fossils on the sample. Bring the rock sample up to your teacher and have your worksheet initialed.

Questions:

1.        Identify three fossils from your sample.

        A.        Fossil name:

                Teacher’s Initial:

        B.        Fossil name:

                Teacher’s Initial:

        C.        Fossil name:

                Teacher’s Initial:

2.        What kind of rock are these fossils contained in? (Be specific.)

3.        During what time period did these plants and animals live?

4.        How long ago was that?

5.        What type of fossils are these? (Land or Marine)

6.        What was Minnesota like 450 million years ago?

7.        What type of rock are these fossils contained in? 

        (igneous, sedimentary, metamorphic)