Imaging the lithosphere and upper mantle: where we are at and where we are going

Hypotheses and conclusions concerning the physical state of the interior of the Earth are under constant debate. At least part of the controversy lies in the fact that traditionally studies of different nature (i.e., seismic, geochemical, electromagnetic, etc.), with very different spatial and temporal resolutions and sensitivities to the thermochemical structure of the Earth’s interior, have been used in isolation to explain the same phenomena (e.g., temperature or velocity anomalies, magmatism, plate motion, strain partitioning, etc.). There is no a priori reason, however, why the results from these diverse studies should be strictly comparable, consistent, or compatible, despite sampling the same physical structure. In recent years, however, advances on computational power, inversion methods, and laboratory experimental techniques, as well as the dramatic increase on both quality and quantity of multiple geophysical and geochemical datasets, have created great interest on integrated (joint) multidisciplinary analyses capable of exploiting the complementary benefits of different datasets/methods. This chapter endeavors to provide a comprehensive review of the current state of the art in such integrated studies of the lithosphere and sublithospheric upper mantle, as well as of their benefits and limitations. Although important stand‐alone (single‐data) methods are briefly discussed, the emphasis is on forward, inverse, and probabilistic techniques that integrate two or more datasets into a formal joint analysis. The role of emerging trends for imaging the Earth’s interior and their potential for elucidating the physical state of the planet are also discussed.