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.

Subscribe via EMail to the GeoWord of the Day.

equatorial limb . A term sometimes applied to the amb of a pollen grain or spore. It is undesirable because of possible confusion. Syn: limb [palyn].

ahlfeldite (ahl'-feld-ite). A brownish-pink monoclinic mineral: NiSe4+O3•2H2O . It is isostructural with clinochalcomenite and cobaltomenite.

lowmoor peat . Peat occurring on low-lying moors or swamps and containing little or no sphagnum. Its moisture is standing surface water and is low in acidity. Mineral matter and nitrogen content is high compared to highmoor peat; cellulose content is low. Cf: highmoor peat; planar peat; topogenous peat. Syn: fen peat.

conchiolin (con-chi-o'-lin). A fibrous protein, C3H48N9O11, that constitutes the organic basis of most mollusk shells; e.g. the material of which the periostracum and organic matrix of the calcareous parts of a mollusk shell are composed. Syn: conchyolin.

lintisite . A colorless to pale yellow monoclinic mineral: Na3LiTi2O2(SiO3)4•2H2O.

macrophagous (mac-roph'-a-gous). Said of an organism that feeds on relatively large particles. Cf: microphagous.

rhombic-pyramidal class (rhom'-bic-py-ram'-i-dal). That crystal class in the orthorhombic system having symmetry mm2.

three-dimensional survey . A survey involving collecting data over an area with the objective of determining spatial relations in three dimensions, as opposed to determining components along separated survey lines. The data from such a survey constitute a volume which can be displayed in different ways. Abbrev: 3-D. See also: time slice; horizon slice; fault slice; arbitrary line; attribute [seis].

hauckite (hauck'-ite). A light yellow to orange hexagonal mineral: (Mg,Mn2+)24Zn18Fe3+3(SO4)4(CO3)2(OH)81 .

equilibrated chondrite . A chondrite whose major mineral constituents (chondrules, matrix, and metal) have equilibrated during thermal metamorphism. These meteorites are of petrographic (petrologic) grade 4, 5, 6, or 7.


Subscribe to GeoWord of the Day