Is basalt a diabase?

Diabase (/ˈdaɪ. əˌbeɪs/), also called dolerite (/ˈdɒl. əˌraɪt/) or microgabbro, is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro.

What is a diabase rock?

Diabase is a fine-grained igneous rock that would have formed when molten rock material cooled rapidly on or near the surface of the Earth.

What type of igneous rock is diabase?

Diabase is an intrusive igneous rock with the same mineral composition as basalt.

What is diabase texture?

diabase, also called Dolerite, fine- to medium-grained, dark gray to black intrusive igneous rock. In diabase, poorly formed pyroxene crystals wrap around or mold against long, rectangular plagioclase crystals to give it the characteristic texture known as diabasic or ophitic.

How do I know if I have diabase?

Diabase is best identified in thin section with a petrographic microscope, with x-ray diffraction, or with other instruments that can identify the component minerals and their relative abundances.

What minerals are found in diabase?

Diabase is dense, hard, and sparsely fractured. It is composed mostly of plagioclase (An50-70), clinopyroxene (mostly augite) and magnetite +/- ilmenite. Accessory minerals include apatite, quartz, alkali feldspar, hornblende, titantite, and zirocon. Olivine is rare.

Is diabase the hardest rock?

The strongest rock in the world is diabase, followed closely by other fine-grained igneous rocks and quartzite. Diabase is strongest in compression, tension, and shear stress. If mineral hardness is the determining factor of strength then diamond is technically the strongest rock in the world.

Is gabbro a diabase?

Diabase is actually a variety of gabbro which consists mainly of labradorite feldspar, augite, magnetite, and olivine. The grain size of diabase is on the smaller side. Diabase and gabbro have the same general mineral composition as basalt, but they have a larger grain size.

What types of rock is gabbro?

1 Mafic Intrusive Igneous Rocks. Gabbro is a mafic intrusive coarse-grained rock with allotriomorphic texture. Gabbros contain low silicon (no Quartz or Alkali feldspar) and essentially of ferromagnesian minerals and Plagioclase feldspar rich in calcium.

How strong is diabase?

The strongest rock in the world in compression is Diabase, which can stand up to 350 MPa.

What do basalt diabase and gabbro have in common?

Diabase and gabbro have the same general mineral composition as basalt, but they have a larger grain size. Because extrusive rocks make contact with the atmosphere they cool quickly, so the minerals do not have time to form large crystals.

What is the difference between basalt and gabbro?

Gabbro and Basalt are Related Gabbros are equivalent in composition to basalts. The difference between the two rock types is their grain size. Basalts are extrusive igneous rocks that cool quickly and have fine-grained crystals. Gabbros are intrusive igneous rocks that cool slowly and have coarse-grained crystals.

What is the difference between basalt diabase and gabbro?

The difference between basalt, diabase, and gabbro is in their grain size – which was determined by their cooling rates. Basalt: rapid cooling in a lava flow produced individual crystals that are so small they are difficult to see with the unaided eye.

What type of rock is diabase?

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.

What type of rock is gabbro made of?

Chemically, slow-cooling, coarse-grained gabbro is equal to rapid-cooling, fine-grained basalt. Most of the oceanic crust on Earth is made up of gabbro rocks. This rock type forms at mid-ocean ridges. We can also find gabbro in plutons that are associated with continental volcanism.

What is a microgabbro rock?

The term “microgabbro” is sometimes used to refer to such rocks. Diabase with notable plagioclase phenocrysts from La Palma, Canary Islands. Width of sample is 5 cm. Diabase is composed of plagioclase feldspar (mostly labradorite) and pyroxene ( augite ).