Bina, C. R., Seismological constraints upon mantle composition, in Treatise on Geochemistry, vol. 2 (ed. R. Carlson), 39-59, Elsevier Science Publishing, 2003.
Introduction. Direct sampling of mantle rocks and minerals is limited to tectonic slices emplaced at the surface (see Chapter 2.04), smaller xenoliths transported upwards by magmatic processes (see Chapter 2.05), and still smaller inclusions in such far-traveled natural sample chambers as diamonds (see Chapter 2.05). Because of such limited direct access to mantle materials, knowledge of mantle structure, composition, and processes must be augmented by geophysical remote sensing. What can various seismological observations tell us about the major-element composition of the upper mantle? How can they constrain possible differences in chemical composition between the upper and lower mantle? What light can they shed upon the nature of velocity heterogeneities in both the upper and lower mantle? It is these questions that we shall seek to address in this chapter.Copyright © 2003 Elsevier Science B.V.