Oceanic crust Oceanic crust Oceanic crust is the uppermost layer of the oceanic portion of a tectonic plate. It is composed of the upper oceanic crust, with pillow lavas and a dike complex, and the lower oceanic crust, composed of troctolite, gabbro and ultramafic cumulates. The crust overlies the solidified and uppermost layer of the mantle. The crust and the solid mantle layer together constitute oceanic lithosphere. Oceanic crust is primarily composed of mafic rocks, or sima, which is rich in iron and magnesium. It is thinner than continental crust, or sial, generally less than 10 kilometers thick; however it is denser,
The Core as those found in "The Core". In a poll of hundreds of scientists about bad science fiction films, "The Core" was voted the worst. On February 21, 2010, "The Guardian" ran an article about American professor Sidney Perkowitz's proposals to curb bad science in science fiction movies. In the article, Perkowitz is said to have hated "The Core". "If you violate [the coherent rules of science] you are in trouble. The chances are that the public will pick it up and that is what matters to Hollywood. "The Core" did not make money because people understood the science was so