flat [lake] . (a) The low-lying, exposed, flat land of a lake delta or of a lake bottom. (b) The flat bottom of a desiccated lake in the arid parts of western U.S. Commonly used in the plural.
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calcite bubble . A nonattached hollow sphere, usually of calcite, that has formed around a gas bubble on the surface of a cave pool. Syn: cave bubble .
glance . A mineral that has a splendent luster; e.g. chalcocite, or copper glance.
radiolarian ooze . A deep-sea pelagic sediment containing at least 30% opaline-silica tests of radiolarians. It is a siliceous ooze.
kinoite (kin'-o-ite). A blue monoclinic mineral: Ca2Cu2Si3O8(OH)4 .
Båth's law . A generalization in seismology that the largest aftershock occurring within a few days of a main shock has a magnitude of 1.2 units lower than that of the main shock (Richter, 1958, p.69).
conotheca (co-no-the'-ca). (a) Conoidal theca with a small circular aperture located at the terminus of a short neck developed irregularly in colonies of tuboid graptolithines (Whittington and Rickards, 1968). (b) The outer shell of ectocochleate cephalopods and of the phragmocone of endocochleate cephalopods.
fenitization (fen''-it-i-za'-tion). As generally used today, widespread alkali metasomatism of quartzo-feldspathic country rocks in the environs of carbonatite complexes.
Wolfcampian (Wolf-camp'-i-an). North American series: lowermost Permian (above Virgilian of Pennsylvanian, below Leonardian).
caltonite (cal'-to-nite). A dark-colored analcime-bearing basanite that contains microphenocrysts of olivine and clinopyroxene in a trachytic groundmass composed of feldspar laths, clinopyroxene, iron oxides, and analcime. It was named by Johannsen (1931) for Calton Hill, Derbyshire, England. Obsolete.