Rock Cycle - Unit 3

Who is attributed with the idea of the rock cycle?

James Hutton

This rock has a glassy surface. It is obsidian, which is created from lava that cools so quickly that no crystals can form on its surface. It can be found near volcanic lava flows, and was often used to make arrowheads because its edges are very sharp. What kind of rock am I?

igneous

draw the rock cycle including the forces that change them from one type to another

draw the rock cycle including the forces that change them from one type to another

how are sedimentary rocks formed?

formed from particles of sand, shells, pebbles, and other fragments of material. Together, all these particles are called sediment. Gradually, the sediment accumulates in layers and over a long period of time hardens into rock. Generally, sedimentary rock is fairly soft and may break apart or crumble easily.

How is metamorphic rock formed?

formed under the surface of the earth from the metamorphosis (change) that occurs due to intense heat and pressure (squeezing). The rocks that result from these processes often have ribbonlike layers and may have shiny crystals, formed by minerals growing slowly over time, on their surface.

How is igneous rock formed?

formed when magma (molten rock deep within the earth) cools and hardens. Sometimes the magma cools inside the earth, and other times it erupts onto the surface from volcanoes (in this case, it is called lava). When lava cools very quickly, no crystals form and the rock looks shiny and glasslike. Sometimes gas bubbles are trapped in the rock during the cooling process, leaving tiny holes and spaces in the rock.

What processes are involved in changing a rock from one type to another over very long periods of time?

heat, pressure, melting, cooling, weathering, erosion, compacting, cementing

What is the difference between the 3 types of rocks?

how they are formed

Usually, what is the only type of rock that contains fossils?

Sedimentary

What is the difference between extrusive igneous rock and intrusive igneous rock?

When magma rises from deep within the earth and explodes out of a volcano, it is called lava, and it cools quickly on the surface. Rock formed in this way is called extrusive igneous rock. It is extruded, or pushed, out of the earth's interior and cools outside of or very near the earth's surface. What if the magma doesn't erupt out of a volcano, but instead gets pushed slowly upward toward the earth's surface over hundreds, thousands, or even millions of years? This magma will also cool, but at a much slower rate than lava erupting from a volcano. The kind of rock formed in this way is called intrusive igneous rock. It intrudes, or pushes, into the earth's interior and cools beneath the surface.

This rock has gas bubbles. These bubbles form when hot lava from a volcano contains gases that escape from the rock as the lava cools. This is basalt. Usually very dark in color, basalt is the most common rock type in earth's crust and makes up most of the ocean floor. What kind of rock am I?

igneous

What type of rock is most likely to have gas bubbles?

igneous

What type of rock might have a glassy surface?

igneous

What type of rock might have crystals?

metamophic

This rock has crystals. This is marble. It is formed when limestone is pushed down into the earth and subjected to intense heat and pressure for a long period of time. Some marble is pure white, while some has colorful swirls. Marble is found in mountainsides and quarries (pits dug into the earth) and is often used in construction and sculpture. What kind of rock am I?

metamorphic

This rock has ribbonlike layers. It is gneiss (pronounced "nice"). Gneiss forms from other rocks that have been squeezed and heated for a long time deep within the earth's crust. Gneiss can often be seen on mountainsides, where rocks formed below the surface have been pushed up by movements in the earth's crust. What kind of rock am i?

metamorphic

What type of rock might have ribbonlike layers?

metamorphic

Sand and pebbles are visible in this rock. It is called conglomerate, which is made up of pebbles, stones, and smaller particles pressed together by the action of waves or water. The rock is often found in large expanses or beds. Finding a bed of conglomerate is a great clue that a river or beach once existed in that location. What kind of rock am I?

sedimentary

What type of rock is most likely to have fossils?

sedimentary

What type of rock might have sand or pebbles?

sedimentary

You can see fossils in this rock. The fossils formed when seashells and the skeletons of marine animals were compressed into the sea floor, along with other sediment. This rock is called limestone, and is often found near oceans and lakes. What kind of rock am I?

sedimentary

What are the three main types of rocks?

sedimentary, metamorphic, igneous