Carbon mantle/primordial

Estimates of the carbon content of the Earth indicate that it too is a major component of the Earth s volatile budget. Tingle (1998) estimated that the primordial carbon content of the Earth was between 1024 and 1025 g. This is many orders of magnitude greater than the total carbon at the Earth s surface, and even allowing for carbon stored in the Earth s core implies that the mantle is a huge carbon reservoir. Precisely locating this carbon, however, is more difficult and this topic is discussed more fully in Chapter 5, Section 5.1.2. 

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