01:460:110 Lecture Notes - Lecture 3: Continental Crust, Tape Recorder, Ferrari 312B
Document Summary
Rigidity: the earth"s lithosphere is broken into a series of rigid plates justified by fit of continents. Construction/destruction: plates are created at mid ocean ridges and destroyed at subduction zones; steady state. Modern tectonic plates move slowly, averaging several cm (a few (cid:922)(cid:927)c(cid:921)(cid:918)(cid:932)) (cid:929)(cid:918)(cid:931) y(cid:918)a(cid:931) (cid:919)a(cid:932)(cid:933) a(cid:932) y(cid:928)(cid:934)(cid:931) (cid:919)(cid:922)(cid:927)(cid:920)(cid:918)(cid:931)(cid:927)a(cid:922)l (cid:920)(cid:931)(cid:928)w(cid:932). Not only is there symmetry of the magnetic signature on the seafloor but there is also a similar symmetry with respect to age of the volcanic rocks making up the seafloor relative to the mor . Youngest ocean crust is at mor (red) and the oldest ocean crust is generally furthest from the. India and china combined to make the highest mountain chain on earth. Earthquake studies of oceanic ridges and trenches provided key evidence needed to further support the emerging theory of plate tectonics. Wilson, made a major contribution by noting lateral sliding movement at faults near mors connecting the spreading movements taking place at adjacent ridge segments (fig.