Science Station Metamorphic and Sedimentary Rocks

Welcome Welcome to today’s lesson. Today we will review Igneous Rocks and learn about Metamorphic and Sedimentary Rocks.

Rock Review During our last lesson, we learned that there are three different types of rock: 1.Igneous Rock 2.Metamorphic Rock 3.Sedimentary Rock

Rock Review We also learned that rocks go through a rock cycle just like plants and humans.

Rock Review Finally, we discussed one particular type of rock, Igneous Rocks. Igneous Rocks are created when molten lava cools and hardens. When a volcano erupts you would see lava pouring out of the top of the volcano. This lava would eventually cool down and turn into a hard rock, Igneous Rock.

Rock Review You can also find Igneous Rock under the ground, in Earth’s mantel. When lava is still underground it is called magma. When magma cools it also turns into Igneous Rock.

Metamorphic Rocks “Metamorphic rocks“Metamorphic rocks are rocks that have changed. The word comes from the Greek "meta" and "morph" which means to change form. Metamorphic rocks were originally igneous or sedimentary, but due to movement of the earth's crust, were changed.”

Metamorphic Rocks “If you squeeze your hands together very hard, you will feel heat and pressure. When the earth's crust moves, it causes rocks to get squeezed so hard that the heat causes the rock to change. Marble is an example of a sedimentary rock that has been changed into a metamorphic rock.”

Metamorphic Rocks “Metamorphic rocks are the least common of the 3 kinds of rocks. Metamorphic rocks were igneous or sedimentary rocks that have been transformed by great heat or pressure.”

Metamorphic Rocks “Foliated metamorphic rocks have layers, or banding. Slate is transformed shale. It splits into smooth slabs.”

Metamorphic Rocks “Schist is the most common metamorphic rock. Mica is the most common mineral.”

Metamorphic Rocks “Gneiss has a streaky look because of alternating layers of minerals.”

Metamorphic Rocks “Non-foliated metamorphic rocks are not layered. Marble is transformed limestone.”

Metamorphic Rocks “Quartzite is very hard.” Information from:

Metamorphic Rocks You don’t need to recognize the different types of metamorphic rocks. I just want you to see the different types!

Sedimentary Rocks “When mountains are first formed, they are tall and jagged like the Rocky Mountains on the west coast of North America. Over a long time mountains become old mountains like the Appalachian Mountains on the east coast of Canada and the United States.”

Sedimentary Rocks “When mountains are old, they are rounded and much lower. A lot of rock gets worn away due to erosion. Rain, freeze/thaw cycle, wind and running water cause the big mountains to crumble a little bit at a time, i.e. EROSION.”

Sedimentary Rocks New – Rocky Mountains Old – Appalachian Mountains

Sedimentary Rocks “Eventually most of the broken bits of the rock end up in the streams & rivers that flow down from the mountains. These little bits of rock & sand are called sediments.”

Sedimentary Rocks “When the water slows down enough, these sediments settle to the bottom of the lake or oceans. Over many years, layers of different rock pieces settle at the bottom of lakes and oceans.”

Sedimentary Rocks “Think of each layer as a page in a book. One piece of paper is not heavy. But a stack of telephone books is very heavy & would squish anything that was underneath. Over time the layers of sand and mud at the bottom of lakes & oceans turned into rocks. These are called sedimentary rocks.”sedimentary rocks

Sedimentary Rocks

Some examples of sedimentary rocks are sandstone and shale.

Sedimentary Rocks “Sedimentary rocks often have fossils in them. Fossils are plants and animals that have died and got covered up by new layers of sediment and are turned into stone. Most of the fossils we find are of plants & animals that lived in the sea. They just settled to the bottom.”fossils

Sedimentary Rocks “Sedimentary rocks cover 75% of the earth’s surface. Most of the rocks found on the Earth’s surface is sedimentary even though sedimentary rocks only make up less than 5% of all the rocks that make up Earth.” Information from:

Great work today learning about Metamorphic and Sedimentary Rocks. During our next lesson we will review the 3 types of rocks! Next Time