Lithosphere-Asthenosphere boundary 100 km deep. Lithosphere-Asthenosphere boundary The Lithosphere-Asthenosphere boundary (LAB) represents a mechanical difference between layers in Earth’s inner structure. Earth’s inner structure can be described both chemically (crust, mantle, core) and mechanically. The Lithosphere-Asthenosphere boundary (referred to as the LAB by geophysicists) lies between Earth's cooler, rigid lithosphere and the warmer, ductile asthenosphere. The actual depth of the boundary is still a topic of debate and study, although it is known to vary according to the environment. The LAB is determined from the differences in the lithosphere and asthenosphere including, but not limited to, differences in grain size, chemical composition,
Theory of the Earth Theory of the Earth Theory of the Earth was a publication by James Hutton which laid the foundations for geology. In it he showed that the Earth is the product of natural forces. What could be seen happening today, over long periods of time, could produce what we see in the rocks. This idea, uniformitarianism, was used by Charles Lyell in his work, and Lyell's textbook was an important influence on Charles Darwin. The work was first published in 1788 by the Royal Society of Edinburgh, and later in 1795 as two book volumes. Hutton recognized that rocks record the