________ is a dark, fine- grained extrusive rock. Examples of this rock type are the rocks that make up the bulk of the oceanic crust and is exhibited in a flow on the west side of Albuquerque, New Mexico.
Basalt is mafic fine-grained extrusive igneous rocks that are formed form rapid cooling of the magnesium and the iron-rich lava, more than 90% of the rocks makes the bulk of the oceanic crust and are also seen on the new Mexico western side.
It has lower viscosity due to the low silica content and has a rapid flow that can spread over larger areas on cooling. Its usually dark grey to black in color, and weathers to brown and red due to the oxidization process.
