Extrusive rock instead becoming a natural glass or obsidian. If the magma contains abundant volatile components which are released as free gas, then it may cool with large or small vesicles (bubble-shaped cavities) such as in pumice, scoria, or vesicular basalt. Examples of extrusive rocks include basalt, rhyolite, andesite, obsidian and pumice. Extrusive rock Extrusive rock refers to the mode of igneous volcanic rock formation in which hot magma from inside the Earth flows out (extrudes) onto the surface as lava or explodes violently into the atmosphere to fall back as pyroclastics or tuff.This is as opposed to intrusive rock formation, in
Magma Geopark magma and high mountains. Through millions of years, glaciers helped to form the landscape we see in the area today. The main rock type is anorthosite, which is more common on the Moon than on the surface of Earth. Magma Geopark has several nature, culture, history and industrial attractions for both local visitors or tourists. The area has wide network routes and locations for outdoor activities, such as hiking, biking, climbing, kayaking. The geoVR virtual exhibition is now ready for the public in the centre of Egersund. From 1 June at the office located in Elvegaten 23 you can also