Tutor profile: Taylor D.
What are the three types of rock?
The first thing to consider is that any one type of rock can be "transformed" into another. We typically refer to this process as the "rock cycle", however, there is not one beginning and one end. Igneous rocks are crystalline which form directly from cooling magma and are named based on their composition and the size of their crystals. Metamorphic rocks are formed from introducing heat and pressure to an igneous, sedimentary, and yes, even another metamorphic rock. Lastly, sedimentary rocks form from the weathering and erosion of rocks or the precipitation of minerals on a surface.
Subject: Environmental Science
What is sand made of?
Sand is typically composed of quartz. This is for a variety of reasons: the first is that quartz is incredibly resistant to weathering. The second reason is that the two elements that make up quartz (silicon and oxygen) are the two most abundant on Earth's crust. There are however a few locations on Earth that do not have sand primarily composed of quartz. These locations are often very close to volcanoes and have different minerals being sourced to the region.
Subject: Earth Science
Why do all of the continents look like they all fit together?
The Earth consists of "plates" that move along the surface. These plates move because of convection occurring in the mantle that transports hot material up towards the surface and cold material down. This process acts like a conveyor belt that constantly recycles rocks all over Earth.
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