filter feeder . An animal that obtains its food by removing particulate organic matter from water that passes through a part of its body used as a filter; e.g., bryozoans, barnacles, bivalves. Cf: suspension feeder.
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boralsilite . A colorless or white monoclinic mineral: Al16B6O30(Si2O7).
natural remanent magnetization . The entire remanent magnetization of a rock as measured in the absence of an inducing magnetic field. Abbrev: NRM. Syn: natural remanence; natural remanent magnetism.
mesogenetic (mes''-o-ge-net'-ic). A term for the period between the time when newly buried deposits are affected mainly by processes related to the depositional interface ( eogenetic stage) and the time when long-buried deposits are affected by processes related to the erosional interface ( telogenetic stage). Also applied to the porosity that develops during the mesogenetic stage (Choquette and Pray, 1970, p.220).
stream gradient . The angle between the water surface or the channel floor and the horizontal, measured in the direction of flow; the "slope" of the stream. Cf: law of stream gradients. Syn: stream slope; slope [streams].
detrital mineral . Any mineral grain resulting from mechanical disintegration of parent rock; esp. a heavy mineral found in a sediment or weathered and transported from a vein or lode and found in a placer or alluvial deposit.
dypingite (dy'-ping-ite). A white mineral: Mg5(CO3)4(OH)2•5H2O .
fault basin . A depression separated from the surrounding area by faults.
jacutinga (jac-u-tin'-ga). A term used in Brazil for disaggregated, powdery itabirite, and for variegated thin-bedded high-grade hematite iron ores associated with and often forming the matrix of gold ore. Etymol: from its resemblance to the colors of the plumage of Pipile jacutinga, a Brazilian bird.
WWV . Radio station of the U.S. Bureau of Standards, which broadcasts time and frequency standards. WWV (Ft. Collins, Colorado) and WWVH (Maui, Hawaii) broadcast continuously on 2.5, 5, 10, 15, 20, and 25 MHz (the last 2 only by WWV). WWV is off the air for 4 min commencing at 45 min 15 s after each hour and WWVH for 4 minutes commencing at 15 min 15 s after each hour. Each second is marked by a signal or tick. A voice announcement is given every minute, e.g., "National Bureau of Standards, WWV, Fort Collins, Colorado. At the tone, 17 hr, 16 min, Coordinated Universal time."