Noun. 1. heat sink-a metal conductor specially designed to conduct (and radiate) heat. conductor-a device designed to transmit electricity, heat, etc. sink - (technology) a process that acts to absorb or remove energy or a substance from a system; the ocean is a sink for carbon dioxide.
The crust is composed of many different types of rocks that fall within three main categories: igneous, metamorphic and sedimentary. However, most of those rocks originated as either granite or basalt. The mantle beneath is made of peridotite. Bridgmanite, the most common mineral on Earth, is found in the deep mantle. How We Know the Earth Has a Crust
Although the Archean crust is made up of many different types of rocks the most abundant rocks occur in greenstone belt s and granite-gneiss complexes. Granite-gneiss complexes are actually composed of a variety of rocks, with granitic gneiss and granitie plutonic rocks being the most common.