Igneous Rocks Granite To Gabbro

Gabbro ˈ ɡ æ b r oʊ is a phaneritic coarse grained mafic intrusive igneous rock formed from the slow cooling of magnesium rich and iron rich magma into a holocrystalline mass deep beneath the earth s surface.

Igneous rocks granite to gabbro.

Unlike granite gabbro is low in silica and has no quartz. Gabbro is a dark medium to coarse grained intrusive igneous rock composed of calcium plagioclase pyroxene and minor olivine but no quartz. By the weathering of pre existing rocks. Intrusive igneous rocks crystallize below earth s surface and the slow cooling that occurs there allows large crystals to form.

Medium or coarse grained rocks gabbros dark green pyroxene in principle augite and smaller orthopyroxene amounts plus white or green colored plagioclase and black millimeter sized grains of magnetite and or ilmenite. What are igneous rocks. Examples of intrusive igneous rocks are diabase diorite gabbro granite pegmatite and peridotite. When the magma solidifies within the earth s crust it cools slowly forming coarse textured rocks such as granite gabbro or diorite.

Is caused by leaching. The central cores of major mountain ranges consist of intrusive igneous rocks usually granite. It is the most abundant rock in the deep oceanic crust. Granite is a medium tocoarse grained acid igneous rock with essential quartz 20 and feldspar where alkali feldspar constitutes between 100 and 35 of the feldspars and minor mafic minerals.

When exposed by erosion these cores called batholiths may occupy huge areas of the earth s surface. It means that it formed as magma cooled slowly in the crust. Igneous rocks with similar composition are basalt extrusive equivalent of gabbro and diabase the same rock type could be named dolerite or microgabbro instead. Gabbro with large augite phenocrysts embedded in white plagioclase.

Also gabbro has no alkali feldspar only plagioclase feldspar with a high calcium content. It is usually black or dark green in color and composed mainly of the minerals plagioclase and augite. Gabbro is a dark colored igneous rock that is considered to be the plutonic equivalent of basalt. Granite is made from three commonplace minerals quartz mica and feldspar and when viewed from a distance appear tan pinkish or gray relying at the concentrations and grain sizes of the 3 minerals.

Gabbro is a coarse grained and usually dark colored igneous rock it is an intrusive rock. Trapped deep within the earth magma is authorized to cool slowly. Determines the color of the rock. Igneous rocks are formed from the solidification of molten rock material.

Examples of intrusive rocks are granite and gabbro. Records the rock s cooling history. There is a gabbro intermediate or low silica content and rarely contains quartz. Slow cooling coarse grained gabbro is chemically equivalent to rapid cooling fine grained basalt much of the earth s oceanic crust is made of gabbro formed at mid ocean.

Igneous rock is formed. The texture of an igneous rock. Gabbro is a coarse grained dark colored intrusive igneous rock.