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presents what it claims is evidence for vast time spans.
This is graphically illustrated in a chart on pages 36–37: man’s existence is in such a tiny segment at the end of a 5-billion-year time-line that it has to be diagrammatically magnified twice to show up.
If we neglect to ask how the greenhouse effect of various gases is quantified in terms of real, measurable thermodynamic properties, the idea of anthropogenic global warming may well survive long enough for us to ask how the carbon budget establishes that observed increases in CO is one of the lightest volatiles (materials of relatively low melting point), found in the mantle (Wilson, 1989).
The fluid nature of the aesthenosphere, or upper mantle of the earth, ensures that lighter volatiles are fractionated, buoyed towards the surface, and either extruded or outgassed into the atmosphere via volcanoes and faults.
Since their constituent minerals are crystallized from molten material, igneous rocks are formed at high temperatures.
They originate from processes deep within the Earth—typically at depths of about 50 to 200 kilometres (30 to 120 miles)—in the mid- to lower-crust or in the upper mantle.
The Redkino, Kotlin and Rovno regional stages have been substantiated in the type area of the Vendian on the basis of the abundant organic-walled microfossils, megascopic algae, metazoan body fossils and ichnofossils.
Metamorphic rocks are often formed by processes deep within the Earth that produce new minerals, textures, and crystal structures.