Permian (Per'-mi-an). The uppermost system of the Paleozoic Erathem of the Standard Global Chronostratigraphic Scale, above the Carboniferous and below the Triassic System of the Mesozoic Erathem. Also the time during which these rocks were formed, the Permian Period, covering the time span between 295 and 250 Ma. It is named after the province of Perm, Russia, where rocks of this age were first studied.
wave-built terrace . A gently sloping coastal feature at the seaward or lakeward edge of a wave-cut platform, constructed by sediment brought by rivers or drifted along the shore or across the platform and deposited in the deeper water beyond. Cf: marine terrace; beach plain. Syn: wave-built platform.
formation evaluation . The process of evaluating gas- or oil-bearing formations penetrated by a well or wells, and of appraising their commercial significance.
interval scale . A continuous scale of measurement that has an arbitrary origin and in which the differences between successive units of the scale are constant. The Celsius and Fahrenheit temperature scales are classic examples. Cf: nominal scale; ordinal scale; ratio scale.
suspension feeder . An animal that obtains its food by removing particulate organic matter from water, but not necessarily through the use of a filter. Cf: filter feeder.
suspension feeder . An animal that obtains its food by removing particulate organic matter from water, but not necessarily through the use of a filter. Cf: filter feeder.
water mass . (a) A body of seawater having a characteristic temperature and salinity range defined by a temperature-salinity curve. (b) A mixture of two or more water types. See also: intermediate water; deep water; bottom water [oceanog]; surface water.
lake [coast] . A term loosely applied to a sheet of water lying along a coast and connected with the sea; e.g. one of the shallow (1-2 m deep), interconnected bodies of water in the Florida Bay area, Fla.
