Geology.com offers many pictures of rocks, divided into their fundamental categories of igneous, metamorphic and sedimentary. The igneous rock section divides the rocks into extrusive and intrusive types, with special sections for gabbro, peridotite, tuff and others. The metamorphic rocks are divided into foliated and non-foliated rocks, with 10 separate sections focusing on marble, schist, gneiss and other rocks.Know More
Geology.com further divides sedimentary rocks into clastic, chemical and organic types, with a dozen sections devoted to conglomerate rocks, limestone, siltstone and more.
In addition, the site offers pictures of rocks and explanations of special phenomena regarding rocks such as the sliding rocks of racetrack playa. Further pictures are available of rocks on Mars, which appear to be very similiar to rocks on Earth. Another section offers pictures of lava, explaining and showing how a rock can be molten and liquid.
One gallery of pictures features types of sand from all over the world, with photos of exotic orange, green, black and white sands, among others. A separate photo gallery shows the beauty of individual grains of sand. Another close-up set of photos focuses on the beauty of coal when seen through a microscope.
One further startling photo gallery shows a rockfall at Yosemite National Park, along with the accompanying debris avalanche.Learn more about Geology
Humans use rocks for a wide variety of purposes, including construction and as a source of valuable minerals located inside the rocks. Additionally, humans use rocks for decoration, recreation and thermal purposes. Humans are not the only organisms that utilize rocks, as plants, animals and fungi use rocks for stability, digestive purposes and as a substrate.Full Answer >
Rocks are formed in three primary ways, and each method produces rocks with different characteristics. Rocks are either classified as sedimentary, igneous or metamorphic, depending on the manner in which they were formed. Most rocks encountered in everyday life are sedimentary, although some igneous rocks, such as granite, are also common.Full Answer >
Metamorphic rocks are formed when the properties of existing igneous or sedimentary rocks are altered by contact with heat or pressure. They are typically found deep underground where the conditions necessary for their formation exist.Full Answer >
The most common type of igneous rock, basalt, also known as malfic rock, can be found on oceanic plates at divergent plate boundaries. Intermediate and felsic igneous rocks show up along continental margins, as well. Because igneous rocks form from the cooling of lava and magma, they can be found around areas where volcanic activity is or has been present.Full Answer >