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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).]


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


(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.
References in periodicals archive ?
Subsequently, Fouque and Michel Levy (1879) used a derivative term "ophite" to describe diabase or dolerite.
Behavior of trace and major elements and minerals during early stages of weathering of diabase and granite in Central Wisconsin.
They are geologically favorable to PGMs, as they include mafic intrusive rocks of the River Valley Intrusive and Nipissing Diabase.
The property mineralization hosts two styles of gold mineralization, including near surface, steeply dipping north-northwest striking diabase Dyke Zone, and the east-west trending, steeply dipping gold mineralization in sheared granodiorite similar to the near-by Howey and Hasaga mines.
The purpose of the contract is to develop or replace document and case management system Diabase against a business system as a whole solution handles:
Velocity of seismic waves and crack systems were assigned for Devonian and Triassic limestone, Cretaceous and Oligocene sandstone, Paleogene basalt, Permian porphyry, Permian diabase and Paleozoic granite (Fig.
Mapping in this area also outlined a swarm of diabase dykes and associated diatreme breccias, which were emplaced in the main E-W rift associated with the Richmond Gulf zone (Simard et al.
The ore types were further subdivided into degrees of perceived hardness, which, in the case of the diabase, depended upon the degree of alteration.
Tesla-10 have now added a Geonics EM-31 conductivity-meter to complement their vehicle-borne mobile magnetometer system that is being used to map saline areas and diabase dykes in agricultural areas of Western Australia.
The purpose of this procurement is to develop or replace the document and case management system Diabase towards an operational system that holistically manages.