1. Chapter 1.2
Earth’s Land and Water

2. The lithosphere varies in thickness from about 10 to 200 kilometers (km).
Three main types of rocks make up the lithosphere; igneous rock, sedimentary rock, and metamorphic rock.
Igneous Rock – when liquid rock cools, it solidifies to become this type of rock.
The lava that flows from a volcano can cool to form the igneous rock basalt.
Liquid rock that cools deep within Earth can form the igneous rock granite.

3. Sedimentary Rock – Rocks break down slowly over time, the tiny pieces are called sediment. As layers of sediment accumulate, they become compressed and cemented in to sedimentary rock. Examples; Limestone and Sandstone.
Metamorphic Rock – Rock that has been transformed by heat and pressure. Examples; Marble and Slate.

4. More than 70% of Earth’s surface is covered by water.
More than 97% of the hydrosphere is salt water.
Fresh water takes up less than 3% of the hydrosphere.
There are two types of fresh water:
Surface water – water in lakes, streams, and rain runoff.
Ground water – found beneath the surface of Earth and moves very slowly through small spaces and between rocks.

5. An underground layer of porous rock that contains water is called an aquifer.
When an aquifer reaches the surface of the ground, it is considered a natural spring.
Wells in which water flows to the surface due to high pressure underground are called artesian wells.