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

Quartz porphyry, diabase and diorite appear in the Ardennes.

From Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 1 "Calhoun" to "Camoens" by Various

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.

These rocks are metamorphic, and though having a mineral constitution somewhat similar to that of diorite, they have been produced really from rocks of more basic character, such as diabase, dolerite and gabbro.

From Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 6 "English Language" to "Epsom Salts" by Various

The igneous rocks themselves furnish desirable building stones, such as granite, diorite, porphyry, diabase, etc.

From North America by Russell, Israel C. (Cook)

It is traversed in places by dikes and sills of diabase or dolerite, while bosses of more or less altered gabbro rise through it.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 6 "Groups, Theory of" to "Gwyniad" by Various