Download presentation
Presentation is loading. Please wait.
1
The Rock Cycle
2
Rock Cycle: A rock is a mixture of minerals, mineraloids, glass or organic matter. The rocky cycle shows how one rock changes into another. Rocks are changed by the following: Weathering Erosion Compaction Cementation Melting Cooling
3
Rock Cycle
4
Igneous Rocks Igneous rock- Occurs when molten material from a volcano or from deep inside Earth cools. Most abundant type of rock on Earth. obsidian pumice
5
Igneous Rocks cont. Great pressure and heat melt the rock to form magma Also radioactive elements in rock generate thermal energy Heats rocks Less dense than surrounding rocks, forced upward and released from volcanoes as lava. Lava and magma contain Silica The more silica the more viscous (thick) it is.
6
Metamorphic Rocks Metamorphic Rock- Rocks that have changed due to temperature and pressure increases or that undergo changes in composition Metamorphic Rock Formed from igneous, sedimentary or other metamorphic rock Changes in appearance, texture, crystal, structure, and or mineral content
7
Metamorphic Rocks cont.
Heat and pressure not enough to melt the rock like igneous Pressure and heat flatten rocks, exchanges atoms with other minerals Amount of pressure can determine what rock will form One rock can change into several different rocks i.e. shale will change to slate but as more pressure is applied could change into phyllite, schist, and gneiss
8
Metamorphic Rocks quartzite hornfels marble
9
Sedimentary Rock Sedimentary Rock- Formed when sediments become pressed or cemented together or when sediments precipitate out of solution Sedimentary Rock 75% of Earth’s Surface Formed from sediments Sediments- loose materials such as rock fragments, mineral grains, and bits of plant and animal remains that have undergone weathering and erosion Minerals dissolved in water are also sediments Come from already existing rocks that are weathered and eroded
10
Sedimentary Rocks Cont.
Movement of weathered material is called erosion. Often form layers Oldest layers are at the bottom Except when disturbed by some force within the Earth Compaction Large sediments cannot be compacted alone by pressure Cementation occurs when these large sediments are glued together by minerals deposited b/w the sediments by water
11
Sedimentary rocks conglomerate coquina Limestone breccia
12
Uses of Rock Construction Slate Crushed Brick, Facing, Monuments
Pool tables, Roofs Crushed Roads, Erosion control, concrete
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.