Intrusive vs. Extrusive Igneous Rocks Intrusive igneous rocks from when magma cools slowly under the Earth’s surface. Large crystals Extrusive igneous rocks from when the magma cools quickly on the Earth’s surface. Very small crystals

What is a metamorphic rock? Formed when buried rock is changed under high temperature and pressure Rock doesn’t melt. Instead, new minerals grow and the rock remains solid. Gneiss

Metamorphic Rocks – Characteristics Layering is common in metamorphic rocks Different layers are made up of different minerals Often made of plates and flaky layers

Foliated vs. Nonfoliated Metamorphic rocks Foliated metamorphic rocks has a banded or layered appearance Nonfoliated metamorphic rocks does not have a banded texture

What are sedimentary Rocks? Fossilierous limestone Produced through the process of weathering Large rocks broken down into smaller pieces and transported by wind, water, and ice. Conglomerate

Sedimentary Rocks – Characteristics Often contain layers Look for grains in the rock May contain fossils Shale w/ plant fossils

What is the rock cycle? Continuous process undergone by rocks in the Earth’s crust, by which rocks are created, changed from one form to another, destroyed, and then formed again. Processes of the rock cycle gradual and happens over times that range from thousands to millions of years or longer.

The Rock Cycle

What drives the rock Cycle? Heat from the Earth’s interior are responsible for forming both igneous rocks and metamorphic rocks. Weathering and the movement of weathered materials are surface processes powered by energy from the sun.

What terms do you need to know about Earth’s processes? Weathering is a process by which rocks are broken down due to exposure to processes occurring on Earth’s surface. Erosion is the removal and transport of weathered materials by natural agents Deposition is the process of dropping or depositing solid and sediments.