Here's a breakdown:
* Felsic igneous rocks: These include granite, rhyolite, and other rocks rich in quartz and feldspar. They are typically found in the upper layers of the continental crust.
* Intermediate igneous rocks: These include diorite and andesite, which have a composition between felsic and mafic rocks.
* Metamorphic rocks: These are formed when existing rocks, both igneous and sedimentary, are transformed by heat, pressure, and chemical reactions. Examples include gneiss, schist, and marble.
In addition to igneous and metamorphic rocks, the continental crust also contains a significant amount of sedimentary rocks, such as sandstone, limestone, and shale, which are formed from the accumulation and cementation of sediments.
Key Differences from Oceanic Crust:
* Composition: The oceanic crust is primarily composed of mafic igneous rocks, like basalt and gabbro, which are denser and darker in color than felsic rocks.
* Thickness: The continental crust is much thicker than the oceanic crust, typically ranging from 30 to 70 kilometers, while the oceanic crust is only about 5 to 10 kilometers thick.
* Age: The continental crust is significantly older than the oceanic crust, with some parts dating back billions of years.
Overall, the continental crust is a complex and diverse geological structure that has been shaped by a long history of volcanic activity, tectonic plate movement, and erosion.
