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
1 The crust is about 0.5 % of the earthâs total mass. 2  The crust is made up of silicate rocks such as granite and basalt. 3  The continental crust is much thicker than the oceanic crust as shown here in the diagram of the earth's crust. Continental crust (continental cratons) - Where there are continents the crust is about 30 to 50 km thick. 2  It is made up of igneous, metamorphic, and sedimentary rocks. 3  The continental crust is less dense than the oceanic crust.