Feldspars are the second most common group of minerals on Earth. The are important contributors to soils as they weather relatively easily to form clays. Potassium, Sodium and Calcium are the most common elements in Feldspars passed on to plants and animals, and are all elements critical to human life.
Igneous rocks are rocks derived from the cooling of magma, molten material originating from the upper Mantle/lower crust. Igneous rocks are classified by their texture and their composition. Rocks ' textures range from fine-grained (extrusive/volcanic) or coarse-grained (intrusive/plutonic). Compositions range from silica-rich (felsic) to silica-poor (mafic).
Volcanoes form when magmas make their way to the Earth's surface and erupt. Volcanoes vary by type; cinder cones, stratovolcanoes or shield volcanos. The intensity of the eruption depends in part on the composition if the lava, and following, how much gas is contained within the melt and how viscous (reseitive to flow) the magma is upon reaching the Earth's surface. This episode demonstrates how the release of gas is an importance factor in the violence of a volcanic eruption through the classic baking soda-vinegar volcano, and a more modern analog with diet soft drinks.
This episode discusses the scientific theory of plate tectonics, in which the Earth’s crust is subdivided into a series of large and small tectonic plates. Convergent, divergent or transform boundaries are discussed and demonstrated with brittle graham crackers and icing to illustrate the motions of the plates at these boundaries. A second demonstration consisting of heating cream in a pan, representing convecting upper mantle, driving a relatively brittle layer of cocoa powder (the Crust).