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Tanveer_Computers
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Because of its relatively low density continental lithosphere that arrives at a subduction zone cannot be pushed much further than about hundred km before resurfacing. As a result continental lithosphere is not recycled at subduction zones the way oceanic lithosphere is recycled. Instead continental lithosphere is a nearly permanent feature of the Earth. The concept of the lithosphere as strong outer layer of Earth was described by A.E.H. Love and further developed by Joseph Barrell who introduced the term lithosphere. The concept of lithosphere was based on the presence of significant gravity anomalies over continental crust from which he inferred that there must exist a strong solid upper layer above a weaker layer which could flow. They have been broadly accepted by geologists and geophysicists. These concepts of a strong lithosphere resting on a weak asthenosphere are essential to the theory of plate tectonics.