Which composition of igneous rock is likely to contain the most plagioclase feldspar?

Which composition of igneous rock is likely to contain the most plagioclase feldspar?

granodiorite, medium- to coarse-grained rock that is among the most abundant intrusive igneous rocks. It contains quartz and is distinguished from granite by its having more plagioclase feldspar than orthoclase feldspar; its other mineral constituents include hornblende, biotite, and augite.

Are made mostly of dark colored silicate minerals and plagioclase feldspar?

Mafic igneous rocks
Mafic igneous rocks are iron and magnesium rich and contain abundant pyroxene, and calcium rich plagioclase feldspar. Mafic igneous rocks are dark or black in color.

Which composition type of igneous rock contains a high percentage of dark silicate minerals?

Such rocks are called granitic rock. Rocks which contain large amounts of the ferromagnesian dark matter and about 50% silica are said to have basaltic composition.

What type of silicate is feldspar?

All the rock-forming feldspars are aluminosilicate minerals with the general formula AT4O8 in which A = potassium, sodium, or calcium (Ca); and T = silicon (Si) and aluminum (Al), with a Si:Al ratio ranging from 3:1 to 1:1.

Which igneous rock is dark colored cooled rapidly on Earth surface is composed mainly of plagioclase feldspar olivine and pyroxene?

Basalt
Basalt is a fine-grained, dark-colored extrusive igneous rock composed mainly of plagioclase and pyroxene. The specimen shown is about two inches (five centimeters) across.

Which property is common to most dark colored igneous rocks?

Which property is common to most dark-colored igneous rocks? High density. The table below provides information about the mineral composition of a sample of beach sand from Hawaii.

In what way are the dark silicate minerals different from the light silicate minerals?

(ferromagnesian) silicates, and list four common minerals from each group. The main difference between the light and dark silicates is their relative specific gravities (densities); light silicates are less dense (lower specific gravity) than the dark silicates.

What is a dark colored igneous rock called?

A rock that has a large amount of ferromagnesian minerals in it will be a dark-colored rock because the ferromagnesian minerals (other than olivine) tend to be dark-colored; an igneous rock that is dark in color is called a mafic rock (“ma-” comes from magnesium, and “fic” from ferric iron).

Which rock has highest percentage of dark minerals?

In general, igneous rocks have an increasing proportion of dark minerals as they become more mafic (Figure 7.16). The dark-coloured minerals are those higher in iron and magnesium (e.g., olivine, pyroxene, amphibole, biotite), and for that reason they are sometimes referred to collectively as ferromagnesian minerals.

What is a dark-colored rock containing a large amount of olivine and pyroxene?

mafic rock, in geology, igneous rock that is dominated by the silicates pyroxene, amphibole, olivine, and mica. These minerals are high in magnesium and ferric oxides, and their presence gives mafic rock its characteristic dark colour.

What is the percentage of silica in igneous rocks?

Most igneous rocks contain between 45 and 65 wt% silica. They range from lower-silica basalt and gabbro to higher-silica rhyolite and granite. Other elemental concentrations vary systematically, too.

What is the composition of the Green xenolith?

The green xenolith contains light green olivine, (minor) emerald-green clinopyroxene, and darker orthopyroxene. Igneous minerals crystallize from a magma to form igneous rocks. Magmas have variable compositions giving rise to many different kinds of rocks containing different minerals. Cooling rate affects crystal size and rock texture.

How does magma affect the composition of rocks?

Magmas have variable compositions giving rise to many different kinds of rocks containing different minerals. Cooling rate affects crystal size and rock texture. Minerals crystallize in an orderly and predicable way during magma cooling. Silicates are the most important minerals in igneous rocks.

Do igneous minerals crystallize from magma?

Igneous minerals crystallize from a magma to form igneous rocks. Magmas have variable compositions giving rise to many different kinds of rocks containing different minerals. Cooling rate affects crystal size and rock texture. Minerals crystallize in an orderly and predicable way during magma cooling.