Diabase (/ ˈ d aɪ. ə ˌ b eɪ s /), also called dolerite (/ ˈ d ɒ l. ə ˌ r aɪ t /) or microgabbro, [1] is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. Diabase dikes and sills are typically shallow intrusive bodies and often exhibit fine-grained to aphanitic chilled margins which may ...

2023年8月26日 · Diabase, also known as dolerite, is a type of igneous rock that holds significance in the field of geology due to its unique characteristics and formation process. It is an intrusive rock, which means it forms from molten magma that …

In the United States and Canada, the name " diabase " is used for a dark gray to black, fine-grained, intrusive igneous rock that has a composition similar to basalt and gabbro. The difference between basalt, diabase, and gabbro is in their grain size - …

2023年9月4日 · Diabase, dolerite, or microgabbro is a medium-grained, dark-colored, hypabyssal, or subvolcanic rock with a composition similar to plutonic gabbro or volcanic basalt. It commonly occurs in dikes, sills, and sometimes in plugs, sheeted dikes, laccoliths, or lopoliths.

diabase, fine- to medium-grained, dark gray to black intrusive igneous rock. It is extremely hard and tough and is commonly quarried for crushed stone, under the name of trap. Although not popular, it makes an excellent monumental stone and is one of the dark-coloured rocks commercially known as black granite.

2024年4月11日 · Dolerite, diabase, or formally microgabbro, is a dark-colored, medium-grained subvolcanic rock equivalent to basalt or gabbro in composition. Subvolcanic or hypabyssal rock is a plutonic rock that forms at shallower depths less than 2 km (1.2 mi) from the Earth’s surface. Cooling is a bit faster at these shallower depths than other intrusive ...

Dolerite is an intrusive igneous rock that is composed mainly of plagioclase feldspar and pyroxene. It is formed when magma is intruded into other rocks, and then cools and solidifies underground. Dolerite typically has a fine-grained texture, and is …

Diabase (dolerite) is a dark-colored igneous rock. It is compositionally equivalent to gabbro and basalt but texturally between them. Diabase is a common rock type. It occurs mostly in shallow intrusions (dikes and sills) of basaltic composition.

Dolerite is a holocrystalline subvolcanic rock equivalent to basaltic volcanic rocks or plutonic gabbro. It occurs as dikes (gangue rocks) and sills (stock dikes). Dolerite usually has a fine but visible texture, consisting of euhedral, needle- or rod-shaped plagioclase crystals embedded in a finer matrix of clinopyroxene, typically augite.

Dolerite is the name given to the medium-grained intrusive basic igneous rock commonly found in dykes and sills; in North America and continental Europe it is often referred to as diabase, but many authors restrict this term to altered dolerite.