Table of Contents
Is a basalt rock a igneous rock?
Basalts are common aphanitic igneous extrusive (volcanic) rocks. Basalts are composed of minute grains of plagioclase feldspar (generally labradorite), pyroxene, olivine, biotite, hornblende and <20% quartz.
Is basalt an igneous or metamorphic rock?
extrusive igneous
basalt, extrusive igneous (volcanic) rock that is low in silica content, dark in colour, and comparatively rich in iron and magnesium. Some basalts are quite glassy (tachylytes), and many are very fine-grained and compact.
What is igneous rock question answer?
Answer: The cooling and solidification of magma or lava produce igneous rock. Igneous rock can form either below the surface as intrusive rocks or on the surface as extrusive (volcanic) rocks, with or without crystallisation. This magma can come from partial melts of existing rocks in the mantle or crust of a planet.
What is not an igneous rock?
The correct answer is option 2 i.e., Dolomite. It is a sedimentary rock similar to limestone. It is also known as “dolostone” and “dolomite rock.”
Which is not an igneous rock?
What are called igneous rocks?
Igneous rocks (from the Latin word for fire) form when hot, molten rock crystallizes and solidifies. The melt originates deep within the Earth near active plate boundaries or hot spots, then rises toward the surface.
What is igneous rock examples?
Extrusive Igneous Rock Hot gasses are often trapped in the quenched lava, forming bubbles (vesicles). Types of extrusive igneous rocks include: pumice, obsidian, andesite, rhyolite, and basalt.
Is basalt a sedimentary rock?
Basalt is not a sedimentary rock. It is actually an igneous rock formed from cooled, melted rocks.
How is basalt form?
Basalt (UK: /ˈbæsɔːlt, -əlt/; US: /bəˈsɔːlt, ˈbeɪsɔːlt/) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon.
What’s basalt made of?
Basalt is a dark-colored, fine-grained, igneous rock composed mainly of plagioclase and pyroxene minerals. 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.
What is a basalts in geology?
Clarification: Basalts are volcanic igneous rocks formed by rapid cooling from lava flows from volcanoes either over the surface or under water on oceanic floors. 10. What can be said about the grain size of pegmatite?
Which statement is an example of an intrusive igneous rock?
Rewrite the False Statement Correctly : Basalt is an Example of an Intrusive Igneous Rock. – Geography Write True or False. Rewrite the false statement correctly : Basalt is an example of an intrusive igneous rock. Correct : Basalt is an example of extrusive igneous rock.
What are the questions on important igneous rocks?
Engineering Geology Multiple Choice Questions on “Important Igneous Rocks”. 1. Granite belongs to which mode of occurrence of igneous rock? Clarification: Granites may be defined as plutonic light coloured igneous rocks. These are among the most common igneous rocks.
What does the texture of igneous rocks depend on?
The texture of igneous rocks will depend greatly on: The amount of magnesium they contain. The rate at which they cool. The amount of quartz they contain. Whether or not they contain silica. The amount of iron they contain. Question 29 29. Which of the following minerals would be found abundantly in mafic rocks?