1. The Lithosphere: Introduction to the Land Unit

2. Earth’s Lithosphere
Lithosphere = a layer of land that forms Earth’s surface
Includes the rocks, soil and sand that make up land

3. Earth’s Lithosphere 10-200 km thick
Cool, rigid outermost part of the earth’s mantle
Divided into tectonic plates
Cause earthquakes/ mountain ranges

4. The Lithosphere 10-200 kilometers Rocks making up the lithosphere
Igneous Rock
Sedimentary Rock
Metamorphic Rock

5. Igneous Rock
Formed when magma (molten rock deep within the earth) cools and hardens.
When lava cools very quickly:
no crystals form
rock looks shiny and glasslike
Gas bubbles trapped in the rock during the cooling process
tiny holes and spaces form

6. Igneous Rock Examples Pumice Obsidian Basalt
Other examples include: Diabase, Diorite, Gabbro, Granite, Rhyolite, Scoria

7. Sedimentary Rock
As rock breaks down slowly over time, the tiny pieces of rock that wear off become sediments that are carried away by wind and water.
Sediments settle into layers
Layers of sediment accumulate and are compressed and cemented
Fossils are almost always found in sedimentary rock!!!

8. Sedimentary Rock Examples
Shale = silt particles
Sandstone = sand particles
Limestone = calcium carbonate or calcite (shells of marine organisms)
Other examples include: Breccia, Conglomerate

9. Metamorphic Rock
Formed under the surface of the earth from the metamorphosis (change) that occurs due to intense heat and pressure (squeezing).
Ribbon-like layers
May have shiny crystals, formed by minerals growing on their surface slowly over time

10. Metamorphic Rock Examples
Marble
Slate
Gneiss
Other examples include: Quartzite, Schist, Serpentinite

11. Characteristics Used to Identify Rocks
Crystals Fossils Gas Bubbles
Glassy Surface Ribbon-Like Layers Sand or Pebbles

12. The Rock Cycle