Granite is the most well-known and one of the most common intrusive magmatic (plutonic) rock type. It is formed when an intrusion of viscous magma with high silica content (68-75 wt %) remains under the surface of the earth, where it cools and crystallizes slowly inside the crust.
Granite is the equivalent of its extrusive (volcanic) rock type rhyolite. It is granular and coarse-grained in texture. Its principal minerals are feldspars, quartz, and mica.
Granites can be predominantly white, pink, or gray in color, depending on their mineralogy. Read all
Volcano & eruption special tours Tours dedicated to usually a single volcano currently in eruption. These trip, sometimes offered only last-minute through our newsletter, are among the most adventurous and most popular in our program.
Photos from Armenia Armenia is a very photogenic country with a large variety of landscapes showing some very spectacular geology, century-old monasteries and castles, and much more.
Gorely volcano photos Gorely is a young and very active shield volcano in southern Kamchatka. It is one of Kamchatka's easiest volcanoes to climb and offers stunning views into vast craters and the surrounding landscape.