4a. Draw the rock cycle. State two characteristics of the three (3) main rock types
The rock cycle is a continuous process in which rocks are formed, broken down, and transformed over time. Here is a simplified representation of the rock cycle:
[Diagram of the rock cycle]
Characteristics of the three main rock types:
1. Igneous rocks:
- They are formed from the cooling and solidification of molten rock, either beneath the Earth's surface (intrusive) or on the surface (extrusive).
- They often have a crystalline texture and can contain various minerals, depending on the cooling rate and composition of the magma.
2. Sedimentary rocks:
- They are formed from the accumulation, compaction, and cementation of sediments, which can originate from the weathering and erosion of other rocks, chemical precipitation, or the remains of plants and animals.
- They frequently exhibit layers or strata, and may include fossils and various types of sedimentary structures.
3. Metamorphic rocks:
- They are formed through the alteration of pre-existing rocks (igneous, sedimentary, or other metamorphic rocks) by heat, pressure, and chemical activity without completely melting them.
- They can have a wide range of appearances, textures, and mineral compositions, often exhibiting foliation (parallel mineral alignment) or banding due to the rearrangement of minerals during metamorphism.