1. Pacific Plate: The largest tectonic plate on Earth, it is primarily composed of oceanic crust, which is made up of SIMA.
2. Nazca Plate: Located off the western coast of South America, this plate is also predominantly composed of oceanic crust.
3. Cocos Plate: Situated off the coast of Central America, this plate is largely made up of oceanic crust, similar to the Pacific and Nazca plates.
SIMA is a term used to describe the composition of the Earth's oceanic crust, which is primarily made up of silica (Si) and magnesium (Ma).
It's important to note that while these plates are primarily composed of SIMA, they might contain small portions of continental crust (SIAL) in some areas, particularly at their boundaries.
