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,
And What Will We Do Tomorrow? And What Will We Do Tomorrow? "And What Will We Do Tomorrow" is a short story by Orson Scott Card. It first appeared in his short story collection "Capitol" and then later in "The Worthing Saga". This story is about Mother the empress of Capitol. In it she wakes up from suspended animation for her one waking day every five years and meets with all of her ministers. All of them try lying to her except for the minister of colonization who doesn’t know anything about what is going on in his department. She sends him away and asks to