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IMPLICATIONS OF PLATE TECTONICS 415
Fig. 13.10 Locations of hot brine pools and metalliferous sediments in the Red Sea (redrawn from Bignell et al., 1976,
with permission from the Geological Association of Canada).
where strong ocean currents prevent the accumulation slices of oceanic or backarc basin lithosphere tectoni-
of clastic sediments. These deposits are of hydrous cally emplaced within continental crust during colli-
origin and accumulate slowly, sometimes forming sional orogenesis. One of the most intensively studied
extensive pavements. As well as iron and manganese, bodies of this type is the Troodos complex of Cyprus
they also contain smaller amounts of copper, nickel, (Fig. 13.11), and other examples include ophiolites of
and cobalt. northwestern Newfoundland, the Semail Ophiolite of
In addition to the exhalative processes of mineraliza- Oman, and Ergani Maden in Turkey. At high levels in
tion described above, ore bodies may form within the the lithosphere, massive sulfide deposits (marcasite,
oceanic lithosphere as it is created. Much of our knowl- chalcopyrite and sphalerite) occur on top of or within
edge of these deposits is derived from studies of ophio- the pillow lavas of layer 2. It has been suggested that
lites (Section 2.5), which are interpreted as allochthonous these sulfides formed either in a manner similar to the
