In the TAS classification, this substance is located between a “picro-” counterpart and below a “trachy”form of it. Goldberg et. al studied carbon dioxide sequestration and mineralization with this substance, the subject of Project FAMOUS. This rock is the primary component of stone wool. The tholeiitic (-5[1])type of this rock is low in alkali elements and uranium. A substance named for this rock, which forms (*) MORBs, (10[1])is lower in viscosity and silica and higher in iron than andesitic and rhyolitic forms. This quick-cooling rock is the extrusive equivalent (-5[1])of gabbro. Geomagnetic reversal is supported by the reversal of polarity of this rock at mid-ocean ridges. For 10 points, name this volcanic igneous rock which comprises most of the seafloor. ■END■ (10[1]0[1])