Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
3.2 Igneous Rocks 3 Families Granite – forms from felsic lava Basalt – forms from mafic lava, rich in iron Large crystals From slow cooling Deep underground Plageoclase feldspar & augite Diorite – medium-colored rocks made up of plageoclase feldspar, hornblende, augite, and biotite mica Intrusive Igneous Rocks Cools deep in the earth; Large grains Granite – most common; forms from felsic lava Gray = quartz Pink = feldspar Black = biotite mica Diorite Intrusive rock formations Batholith “deep rock” – over 100 square miles; form the core of many mountain ranges Laccolith – meaning “lake of rock” Sill– sheet of magma flows Dike– follows between rock layers existing vertical fractures Extrusive Igneous Rocks Little to no crystal growth! Rapid cooling Small grains Obsidian volcanic glass Pumice Shiprock, New Mexico Andesite Rhyolite Volcanic neck Lava flows... and Lava plateaus Sedimentary Rock Stratification – changes in type of sediment creating stripes in the rock. Erosion from wind & water 1. Clastic – cemented rock fragments Conglomerate Breccia Sedimentary Rock 2. Chemical – minerals once dissolved in water Halite - salt Limestone Gypsum Sedimentary Rock Special examples... Geodes Fossils Crystal caves Metamorphic Rock Change of one type of rock into another by heat, pressure, and/or chemical processes. Foliated – has visible layers or bands Unfoliated – w/out visible layers