Metamorphic Rocks PDF - SES4U

SES4U​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Name: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Date: Metamorphic Rocks By the end of this lesson, I will be able to describ...

SES4U​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Name: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Date: Metamorphic Rocks By the end of this lesson, I will be able to describe the process by which rocks metamorphosize and classify metamorphic rocks based on their physical properties When high temperatures and pressure combine to alter the texture, mineralogy, or chemical composition of a rock, without melting it, a metamorphic rock forms. The original rock is known as the parent rock. The newly formed metamorphic rock is called the daughter rock. Metamorphism can occur deep beneath Earth’s surface (deep burial), near igneous intrusions, and near converging plate boundaries, all areas of high pressure and/or temperature. These rocks can be divided into two groups: Foliated Metamorphic Rocks These rocks have a layered or banded appearance that is produced by exposure to heat and directed pressure. This directed pressure causes needle-like crystals to line up with their long axes perpendicular to the source of pressure. Non-Foliated Metamorphic Rocks These rocks do not have the layered or banded appearance. Directed pressure was absent during their formation. SES4U​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Name: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Date: Regional Metamorphism Can occur during mountain-building movements of the crust, where extremely large areas of rock are subjected to high temperatures and pressures. Due to Earth’s internal heat, temperature increases with depth and the deeper you travel the more rock layers exist above, resulting in insurmountable pressures. When the pressure is greater in one direction, minerals in the rock align in layers, while hot liquids and gasses deep in the rocks help speed up this process. Local Metamorphism Two flavors of local metamorphism: -​ Contact Metamorphism Compared to regional metamorphism, contact metamorphism causes fewer changes in the rock and affects much less rock. The area for contact metamorphism is rarely larger than 100 meters squared. This process occurs when hot magma moves into rock, heating, reacting and changing it. -​ Deformational Metamorphism Occurs at relatively low temperatures and at high pressures caused by stress and friction, most often at faults where rock masses pass each other. As the masses move, heat from the friction, stress and pressure cause the rock to deform, or change shape. The altered rock usually has the same mineral composition, but shows structural changes. SES4U​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Name: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Date: Practice! 1.​ What is the difference between contact and regional metamorphism? 2.​ Based on the video, what is impact metamorphism? How rare is this type compared to others? 3.​ For each of the metamorphic rocks listed below, identify their parent rocks. i. slate ii. phyllite iii. gneiss iv. Schist 4.​ Knowing that marble is metamorphosed limestone, explain why this is a terrible choice for kitchen counters. Consider the properties of the parent rock.