walkaway VSP . A vertical seismic profile that involves moving the source away from the wellhead between energy injections.
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paint . A term used in SW U.S. for an earthy, pulverulent variety of cinnabar (Thrush, 1968).
aphyric (a-phyr'-ic). Said of the texture of a fine-grained or aphanitic igneous rock that lacks phenocrysts; also a rock exhibiting such texture.
replacement [paleont] . A process of fossilization involving substitution of inorganic matter for the original organic constituents of an organism.
ferribarroisite . A dark green to black monoclinic mineral of the amphibole group, representing barroisite with essential Fe3+: NaCa(Mg3Fe3+2)(Si7Al)O22(OH)2.
palpus (pal'-pus). A term applied either to a pedipalpus (including pedipalpal coxae) or more properly to one of the five segments following the coxa in an arachnid (TIP, 1955, pt. P, p.62). Pl: palpi. Adj: palpal. See also: palp.
isinglass (i'-sin-glass). A syn. of mica, esp. muscovite in thin transparent sheets.
ice gneiss . Frozen ground with ice segregated in laminae so as to resemble a gneissic rock; term used by Taber (1943).
Ontarian (On-tar'-i-an). (a) Stage in New York State: Middle Silurian (middle and lower parts of Clinton Group). (b) An obsolete name for the Middle and Upper Ordovician in New York State.
ankaramite (an-ka'-ra-mite). An olivine-bearing basanite containing numerous pyroxene (usually clinopyroxene) phenocrysts, the former being more abundant than the latter, in a fine-grained groundmass composed of clinopyroxene microlites and calcic plagioclase. It was named by Lacroix in 1916 from Ankaramy, Malagasy.