diabase

American  

[dahy-uh-beys] / ˈdaɪ əˌbeɪs /

noun

Petrology.

1. a fine-grained gabbro occurring as minor intrusions.

2. British. a dark igneous rock consisting essentially of augite and feldspar; an altered dolerite.

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diabase British  

/ ˈdaɪəˌbeɪs /

noun

1. an altered dolerite

2. another name for dolerite

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diabase Scientific  

/ dī′ə-bās′ /

1. A dark-gray to black, medium-grained igneous rock consisting mainly of labradorite and pyroxene. Diabase is compositionally similar to andesite, but has coarser grains. It is commonly found in sills and dikes.

2. Also called dolerite

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Other Word Forms

• diabasic adjective

Etymology

Origin of diabase

1810–20; < French, equivalent to dia- (error for di- two) + base base ¹

Example Sentences

Away from the ranges, the bowlders are generally of some crystalline rock, such as granite and diabase.

From The Geography of the Region about Devils Lake and the Dalles of the Wisconsin by Atwood, Wallace W.

The igneous rocks are commonly acid intrusives of a granite or porphyry type, less commonly intrusives of gabbro and diabase and surface lavas of rhyolite and basalt.

From The Economic Aspect of Geology by Leith, C. K. (Charles Kenneth)

Lenticular intercalations of gabbro, diabase, &c., occur in the Flysch in Calabria on the Pyrenees.

From Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 5 "Fleury, Claude" to "Foraker" by Various

At Gympie, the auriferous area is confined to veins traversing a crystalline diorite, or within a certain limit of its boundary, marked by the presence of fossiliferous diabase tufas.

From Early Days in North Queensland by Palmer, Edward

The sandstone and trap are of the Triassic Period, and the trap of this vicinity is more particularly classified as diabase.

From Transactions of the American Society of Civil Engineers, vol. LXVIII, Sept. 1910 The Bergen Hill Tunnels. Paper No. 1154 by Lavis, F.