plate tectonics

geological theory that is widely accepted today, theory that the Earth's crust is composed of many separate plates which are moving on top of the molten material inside the Earth

Plate tectonics (from Greek  τέκτων, tektōn "builder" or "mason") is a theory of geology that has been developed to explain the observed evidence for large scale motions of the Earth's lithosphere. The theory encompassed and superseded the older theory of continental drift from the first half of the 20th century and the concept of seafloor spreading developed during the 1960s.
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The theory that the Earth's lithosphere consists of large, rigid plates that move horizontally in response to the flow of the asthenosphere beneath them, and that interactions among the plates at their borders cause most major geologic activity, including the creation of oceans, continents, mountains, volcanoes, and earth quakes.

Noun
1. the branch of geology studying the folding and faulting of the earth's crust
(synonym) tectonics, plate tectonic theory
(hypernym) morphology, geomorphology
(class) Pangaea, Pangea