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Related to diabase: anorthosite, dolerite, dunite, pyroxenite


A dark-gray to black, fine-textured igneous rock composed mainly of feldspar and pyroxene and used for monuments and as crushed stone.

[From French diabase, originally meaning "diorite," (now "basalt or gabbro lightly modified by metamorphism"), coined by French mineralogist Alexandre Brongniart (1770-1847), probably from Greek diabasis, a crossing over (from diabainein, to pass through or over; see diabetes; the rock being so called because it is often found as intrusive sills and dikes in other rocks), or perhaps an alteration of an intended French *dibase (di-, two, from Greek di-; see di-1 + base, basis, from Old French; see base1; the rock being so called in reference to feldspar and amphibole, two important constituent minerals of diorite).]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


1. (Geological Science) Brit an altered dolerite
2. (Geological Science) US another name for dolerite
[C19: from French, from Greek diabasis a crossing over, from diabainein to cross over, from dia- + bainein to go]
ˌdiaˈbasic adj
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈdaɪ əˌbeɪs)

a fine-grained gabbro occurring as minor intrusions.
[1830–40; < French, =dia- (error for di- two) + base base1]
di`a•ba′sic, adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
For chemical analysis thirty ore samples (with 0.5 m interval) from the bauxite profile (Figure 2) and three rock samples from diabase unit in the studied district were collected (Fig.
The coarse aggregates included gravel, limestone, granite, and diabase, with nominal maximum sizes varying from 0.75 in to 1.5 inches (1.9 cm to 3.8 cm).
His dissertation dealt with the Logan diabase sills of the Thunder Bay-Lake Nipigon area of Ontario and was supervised by W.W.
M2 EQUITYBITES-February 12, 2018-Uranium Energy Acquires the Canadian Diabase Project from Nuinsco
Uranium Energy announced that the Company has closed a definitive Property Purchase Agreement, with Nuinsco Resources to acquire 100% of the Diabase project located on the south rim of the Athabasca Basin uranium district in Saskatchewan, Canada.
Brace, "Post-failure behavior of a granite and diabase," Rock Mechanics, vol.
The type of asphalt mixture considered in the current study was dense asphalt concrete (AC) with diabase aggregates and conventional or modified bitumen.
It is massive and is mainly comprised of pebbles and boulders of limestone, quartzite, porphyritic rocks, sandstone, gneiss, schist, diabase, etc.
In which [[alpha].sub.E] depends on the source of the aggregate, and [f.sub.ck] and Eci in megapascals (MPa): [[alpha].sub.E] = 1.2 for basalt and diabase; [[alpha].sub.E] = 1.0 for granite and gneiss; [[alpha].sub.E] = 0.9 for limestone; [[alpha].sub.E] = 0.7 for sandstone.
Therefore, we approximated the RM composition to be a diabase. Composition of the plagioclases ranged widely depending on the petrology of the sill sector and also varied from the periphery to the center of each crystal.
Rock wool is obtained from the mineral stone, dolomite, basalt and diabase with the addition of coke (Civic, Vucijak 2014).