what is the origin of vesicles in a basalt
Basalt Basalt with a vesicular texture is called vesicular basalt, when the bulk of the rock is mostly solid; when the vesicles are over half the volume of a specimen, it is called scoria. This texture forms when dissolved gases come out of solution and form bubbles as the magma decompresses as it reaches the surface, yet are trapped as the erupted lava hardens before the gases can escape.
Stone Mountain Stone Mountain is a pluton, a type of igneous intrusion. Primarily composed of quartz monzonite, the dome of Stone Mountain was formed during the formation of the Blue Ridge Mountains around 300â€“350 million years ago (during the Carboniferous period), part of the Appalachian Mountains.[6] It formed as a result of the upwelling of magma from within the Earth's crust. This magma solidified to form granite within the crust five to ten miles below the surface.