GEOG 1010 Lecture 11: Lecture11
Document Summary
Classification is an important part of natural science. Scientists often group similar objects to seek explanations for their origins. Genetic classifications: group items of similar process of origin. Geologists use a 3-category rock genetic classification scheme based on how rocks form. Formed by deposition and precipitation of materials coming from the breakdown of older rocks on earth"s surface . All rocks deteriorate when exposed to the process of weathering all the time. Physical weathering: causes rocks to break down into fragments or mineral grains. Chemical weathering: involves reactions among minerals, the atmosphere, & water, which produces dissolved ions & new minerals. Fragments form clastic sedimentary rock: sandstone is a clastic rock. Sediments of either type accumulate in layers (bedding), compress under their own mass and/or what buries them, and, with cements precipitating, form a hardened mass = sedimentary rock. Formed by the crystallization of molten material called magma.
