Transcript Rock Cycle
Rocks and the Rock Cycle Geology: The study of rocks, minerals and fossils Layers of the Earth crust Crust The surface of the Earth is a very thin layer made of rocks, minerals and clay We live on the crust of the earth Layers of the Earth crust mantle Mantle- Upper and Lower The mantle is the biggest part of the earth; the magma is rich in iron and magnesium Convection occurs here and is thought to drive plate tectonics Layers of the Earth crust mantle Outer Core Outer core The outer core consists of molten iron and magma The outer core rotates giving the Earth a magnetic field Layers of the Earth crust mantle Outer core Inner Core Inner Core The inner core is made of solid iron The closest model of the inner core we have is an iron nickel meteorite The inner core is under extreme pressure How do we know about the layers of the Earth? To date, humans have never drilled through the crust of the Earth. Scientists study where waves from earthquakes end up around the globe. The waves move differently through different densities of material. Minerals Minerals are inorganic (non-living) solid compounds that have a specific chemical formula and crystalline structure. • •Minerals are made up of one or more elements •The combinations of elements and crystal structure give each mineral its characteristics. Minerals Hardness Color Density Crystalline Structure Luster Streak Magnetism Calcite Amethyst Quartz Rocks Biotite mica Rocks are made up of two or more minerals Quartz Potassium Feldspar Classification of Rocks Sedimentary Rocks- Rocks formed from 1) the consolidation of sediments, 2) precipitate from a solution or 3) consolidation of the remains of plants or animals. These rocks may contain fossils. Examples include conglomerate, coquina limestone, red sandstone, and shale Igneous Rock- Rocks formed from the solidification of magma. This may occur either on the Earth’s surface (lava from a volcano) or within the Earth’s crust (magma from a volcano chamber). Examples include basalt, granite, obsidian, and pumice Classification of Rocks Metamorphic Rock- Rocks produced by the transformation of preexisting rock, either sedimentary or igneous, into a texturally or miner logically distinct new rock as a result of high temperature, pressure or both without melting the rock. Examples include schist, gneiss, and anthracite coal Fossils- Traces of plants or animals preserved in rock. The Rock Cycle The Rock Cycle The Rock Cycle is a model used to describe the changes to rocks that take place on the earth. •These changes show how each type of rock is formed. Some of the processes occur at or near the Earth's surface such as weathering, erosion and deposition. •Other processes occur deep below the surface such as melting and increased heat and pressure.