What is a rock?
According to Holt Science and Technology scientists define a rock as " a naturally occurring solid mixture of one or more minerals and organic matter".
So what's the point of rocks?
Rocks are an important natural resource, especially to humans. Early humans used rocks for tools. Rocks have also been used to make buildings, monuments, and roads. Some examples are the Eqyptians who used sedimentary rock for the pyramids and granite an igneous rock used to constunrct the Texas state capitol building.
So what is the Rock Cycle?
The rock cycle is a process which new rock forms from old rock. This rock cycle is made of several processes . Certain geological processes make and destroy rock. The location of rock determines which natural forces will have the biggest impact on the process of changes.
Wait there is different kinds of rocks?
Yes, there is! There is three main types of rocks; Sedimentary, Metamorphic, and Igneous.
Sedimentary rock is formed from particles of sand, shells, pebbles ands other fragments of materials (all these particles are sediment). Gradually the sediment accumulates in layers and over time hardens into rocks. Generally sediment rock is fairly soft and may break apart or crumble easily. Some examples of sedimentary rocks are Conglomerate and Limestone
Metamorphic rock is formed under the surface of the earth from the metamorphosis that occurs due to intense heat and pressure. The rocks that results from these processes often have ribbionlike layers and may have shiny crystals formed by minerals growing slowly over time on their surface. An example of metamorphic rock is Gneiss and Marble.
The last type of rock is Igneous which forms when magma cools and hardens. Sometimes the magma cools inside the Earth and others it erupts to the surface. An example is Basalt and Obsidian.
So what are these processes?
There are about seven different processes that a rock can go through to change. Weathering, erosion, pressure, heat, cooling, melting, compacting, and cementing. They usually go together in some way to vhange the rock.
This is an example of a version of the rock cycle
In conclusion (reflection)
The rock cycle is how rocks change on earth. The different types of rock (Igneous, metamorpic, sedimentary) determine what way it will change or where it will start. There is about 8 processes that a rock can go through to change, that result in different things.
Holt Science Textbook