7. Rock Studies PT.1

• Sedimentary rocks are formed from the compression of dead, shelly sea creatures at the bottom of seas or lakes.
• The Earth's crust is made up of two types of rocks - sedimentary and igneous.
• 'Igneous rocks form when molten magma cools and solidifies either below ground (intrusive) or on the surface (extrusive).'
• 'Metamorphic rocks form when existing rocks change due to heat and pressure deep underground.'
• 'Different types of rocks have different properties based on how they were formed, such as hardness, porosity, permeability, and resistance to erosion.'
• 'Texture refers to the size, shape, arrangement, and distribution of grains within a rock.'
• 'Hardness is determined by the ability of one mineral to scratch another.'
• 'Porosity is the amount of space between particles in a rock that can hold water or air.'
• 'Permeability is the ability of a rock to allow fluids to pass through it.'
• Resistance to erosion depends on factors like grain size and texture.
• igneous rocks - granite, basalt
• sedimentary rocks - sandstone, limestone
• metamorphic rocks - quartz, marble
• The three main types of weathering are physical, chemical, and biological.