the holes in extrusive igneous rocks (lava) are called vesicles. They are formed by gas escaping from the rock when molten, leaving bubbles in the melt which
which may be preserved when the lava solidifies
the holes in extrusive igneous rocks (lava) are called vesicles. They are formed by gas escaping from the rock when molten, leaving bubbles in the melt which which may be preserved when the lava solidifies
extrusive rocks can form from Basaltic Lava and Andesitic Lava. :)
Igneous rocks are classified as either extrusive or intrusive. Extrusive rocks form from lava at or above the ground, and intrusive rocks form from magma below the ground. Granite is intrusive, pumice is extrusive.
Intrusive rocks form within the crust of the Earth while extrusive rocks form on the surface.
Rhyolititcen rocks.
Extrusive rock forms from cooling lava.
At the Earth surface.
Extrusive is a form of igneous rock - it's what you get when the magma is extruded or squeezed out onto the surface in the form of lava.
Some do. These are called extrusive igneous rocks. However a large portion of igneous rocks form beneath the surface. These are intrusive igneous rocks.
Many extrusive volcanic rocks contain holes, or vesicles, which have formed from gases trapped in the magma during eruption. As the lava cools and solidifies, these gases escape, leaving behind the characteristic holes in the rock.
Extrusive igneous rocks are igneous rocks that form above earth's surface. They are usually fine-grained due to the rate in which they cool.
Extrusive rocks form above the surface, cooling quickly and bearing a glassy or fine texture and may be vesicular. Intrusive rocks form below the surface and form slowly, giving it a coarse texture.