Geology for Engineers. Minerals and Rocks (I). Irruputuncu, Chile, Smithsonian. Minerals and Rocks (I). Minerals and Rocks (I). Igneous Rocks. Key Questions: What are igneous rocks? From what are they formed? How do they crystallise? How are they emplaced?. Forms of Igneous Rocks.
Minerals and Rocks (I)
Irruputuncu, Chile, Smithsonian
This classification is based on composition. Formation of phenocrysts on cooling increases the viscosity
Mauna Loa (left) is the largest volcano on Earth, and is one of the most active
Olympus Mons (right) is the largest volcano, and has an area approximately the size of France.
Pumice - froth of felsic volcanic glass
Tuff - pyroclastic texture shows a mixture of rock fragments, pumice, and volcanic ash
Pahoehoe lava flow - Ropy lava - formed when a lava flow skins over while flowing very slowly
Aa lava flow - Jagged lava formed by the shattering of a solid skin that forms over a rapidly moving flow
Intrusion of a dyke
The Brandberg is an intrusion in the Namib desert in western Namibia with a diameter of about 15km and with a height of 2573m is the highest point in Namibia. Southwest of it is the Messum Crater, and behind, the Erongo Mountains