Which type of crust is typically thicker, containing mainly granite?

The type of crust that is typically thicker and contains mainly granite is known as the continental crust. This crust averages about 30 to 50 kilometers in thickness, with some areas, such as mountain ranges, reaching even greater depths. Granite, a light-colored, coarse-grained igneous rock, is the dominant rock type found in continental crust, providing it with significant buoyancy compared to the denser rocks found in oceanic crust.

In contrast, oceanic crust is much thinner, averaging around 5 to 10 kilometers thick, and is primarily composed of basalt, which is denser and significantly different in composition from granite. The lithosphere refers to the rigid outer layer of the Earth that includes both the crust and the upper part of the mantle, but it does not specifically denote the composition of the crust itself. The asthenosphere is a semi-fluid layer beneath the lithosphere that plays a crucial role in plate tectonics but is not classified based on crustal thickness or rock type. Thus, the distinct characteristics of the continental crust—thickness and predominant granite composition—make it the correct answer.