Is Pillow Basalt A Form Of Granite

Basalt is an igneous volcanic rock that forms commonly in oceanic crust and parts of.

Is pillow basalt a form of granite.

Basalt and granite are two types of igneous rocks that we can find on earth. This pillow texture is very common in underwater basaltic flows and is diagnostic of an underwater eruption environment when found in ancient rocks. Basalt wikipedia wikimedia foundation 13 sept. Basalt is a dark colored fine grained igneous rock composed mainly of plagioclase and pyroxene minerals.

Summary of basalt vs. Basalt is more common in oceanic crust while granite is more common in continental crust. Along the mid ocean ridge. Basalt mostly forms lava flows because it is among the least viscous magma types and therefore does not generate explosive volcanic eruptions but sometimes.

Where do pillow basalts form. Pillow lavas are commonly of basaltic composition although pillows formed of komatiite picrite boninite basaltic andesite andesite dacite or even rhyolite are known. Outer part of forming pillow cools very quickly in contact with cold seawater while the interior still fills with molten lava. Summary basalt vs granite.

Basalt can form in a few days to months whereas granite plutons can take millions of years to cool and harden. Pillow basalt is a volcanic igneous rock that forms when lava of basaltic compositionis erupted underwater. Basalt or greenstone dark greenish gray to black tiny to no visible crystalline matrix or grains may have small holes vesicles sometimes filled with silica minerals may form large rounded pillow shapes on outcrop. When basalt erupts underwater or flows into the sea contact with the water quenches the surface and the lava forms a distinctive pillowshape through which the hot lava breaks to form another pillow this pillow texture is very common in underwater basaltic flows and is diagnostic of an underwater eruption environment when found in ancient rocks.

It most commonly forms as an extrusive rock such as a lava flow but can also form in small intrusive bodies such as an igneous dike or a thin sill it has a composition similar to gabbro the difference between basalt and gabbro is that basalt is a fine grained rock while. Which layer of the earth contains the most iron. In general the more felsic the composition richer in silica resulting in an intermediate composition the larger the pillows due to the increase in viscosity of the erupting lava. The rapid cooling of the lava by cold water on all sides forms the pillow shaped bodies which can then break open and extrude more of the hot lava from inside.

The key difference between basalt and granite is that basalt is mostly occurring on ocean floors while granite is in the crust of the earth in all continents. Pillow basalt forms as a result of very rapid cooling. The most common minerals in the earth s crust are.