hypha (hy'-pha). One of the individual tubular filaments or threads that make up the mycelium of a fungus; e.g. a conidiophore. Pl: hyphae.
GeoWord of the Day
The GeoWord of the Day is a free service of the American Geosciences Institute. All of the terms and definitions are from the Glossary of Geology, 5th Edition Revised.
continuous stream . A stream that does not have interruptions in space; it may be perennial or ephemeral, but it does not have wet and dry reaches. Ant: interrupted stream.
terrestrial peat . Peat that is developed above the water table. Syn: terrestric peat.
horotely (hor'-o-tel''-y). A phylogenetic phenomenon characterized by a normal or average rate of evolution. Cf: bradytely; tachytely.
inner sphere adsorption . Adsorption of ions that occurs with the elimination of water of hydration in the space between the adsorbed ion and the surface. The force of retention of ions involves both ionic and covalent bonding. Strong adsorption of anions and cations at variable charge sites in organic matter, oxides, and phyllosilicate edges involves inner sphere adsorption. See also: outer sphere adsorption.
alpine peridotite . A tectonic, not petrologic, term for ultramafic rock, commonly serpentinized and bounded by fault surfaces, marking convergent plate boundaries.
recentered projection (re-cen'-tered). A term preferred by the BNCG (1966, p.33) to the synonym interrupted projection.
dictyonine (dic'-ty-o-nine''). adj. Said of a hexactinellid sponge whose parenchymalia (spicules) form a rigid framework composed of dictyonal strands; more loosely, said of a sponge whose skeleton is composed of subparallel hexactines rigidly fused so that the limits of individual spicules are not apparent. Ant: lyssacine. n. A dictyonine sponge.
conglomeratic sandstone . (a) A sandstone containing 5-30% gravel and having a ratio of sand to mud (silt + clay) greater than 9:1 (Folk, 1954, p.347); a consolidated gravelly sand. (b) A sandstone containing more than 20% pebbles (Krynine, 1948, p.141). Cf: pebbly sandstone.
dirty sand . A term used in electrical prospecting for a sandstone that contains abundant clay and hence can exhibit appreciable membrane polarization and abnormally high electrical conductivity because of surface conduction along the clay minerals.
Pages
