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Content
The limited content within the article is relevant to the topic, contains no distractions, and does not include dated information. However, because of the shortness of this article, there is much room for more information. There could be more discussion on the formation and characteristics of extrusive igneous rocks, including its chemical composition and the crystallization process. Other additional information could include a comparison of the different types of extrusive igneous rocks and a more detailed explanation concerning the difference between intrusive and extrusive igneous rocks. Furthermore, since the article has added a picture on the classification of igneous rocks, an analysis of this information would allow the reader to better understand that picture.

The information presented in the article is written in a scientific manner and does not include confusing jargon. However, the pictures that are included with the article include unexplained jargon such as "aphanitic." Though this is properly linked to another Wikipedia page, it might be better to explain the term within the article.

There are many links within the article that are helpful for understanding terms and examples, but the "See Also" section only points to topics related to underwater volcanic activity (Guyot, Seamount). I think it would be more helpful to link to an article about intrusive igneous rocks.

Tone
The tone of the article is objective, and there are no controversial view points.

Talk Page
This article was labeled a "level-5 vital article" and is a "Stub-Class" rated as "Mid-importance" for two WikiProjects: Volcanoes and Geology. The one conversation on the talk page concerns whether or not this page deserves to exist or whether it should just be on the "volcanic rock" page.

5 Textbook Sources
Schmincke, Hans-Ulrich (2004). Volcanism. New York City, New York: Springer-Verlag. ISBN 3540436502.

Winter, John DuNann (2001)''. An Introduction to Igneous and Metamorphic Petrology.'' Upper Saddle River, New Jersey: Prentice-Hall. ISBN 0132403420.

Németh, Károly; Martin, Ulrike (2007). Practical Volcanology: Lecture Notes for Understanding Volcanic Rocks from Field Based Studies. Budapest, Hungary: Geological Institute of Hungary. ISBN 9789636712594. https://mek.oszk.hu/18000/18027/18027.pdf

Jain, Sreepat (2014). Fundamentals of Physical Geology. New Delhi, India: Springer. ISBN 9788132215394. https://link.springer.com/content/pdf/10.1007%2F978-81-322-1539-4.pdf

Sen, Gautam (2014). Petrology: Principles and Practice. New York City, New York: Springer. ISBN 9783642388002. https://link.springer.com/content/pdf/10.1007%2F978-3-642-38800-2.pdf

Draft
Extrusive rock refers to the mode of igneous volcanic rock formation in which hot magma from inside the Earth flows out (extrudes) onto the surface as lava or explodes violently into the atmosphere to fall back as pyroclastics or tuff. In contrast, intrusive rock refers to rocks formed by magma which magma cools below the surface.

The main effect of extrusion is that the magma cools much more quickly in the open air or under seawater, and there is little time for the growth of crystals. Sometimes, a residual portion of the matrix fails to crystallize at all, instead becoming a natural glass or obsidian.

If the magma contains abundant volatile components which are released as free gas, then it may cool with large or small vesicles (bubble-shaped cavities) such as in pumice, scoria, or vesicular basalt. Examples of extrusive rocks include basalt, rhyolite, andesite, obsidian and pumice, scoria, and feldspar.

Texture
The texture of extrusive rocks is characterized by fine-grained crystals indistinguishable to the human eye, described as aphantic. Crystals in aphantic rocks are small in size due to their rapid formation during eruption. The extrusive rocks scoria and pumice have a vesicular, bubble-like, texture due to the presence of vapor bubbles trapped in the magma.

Extrusive Bodies and Rock Types
Shield volcanoes are large, slow forming volcanoes that erupt fluid basaltic magma that cools to form the extrusive rock basalt. Basalt is composed of minerals readily available in the planet's crust, including feldspars and pyroxenes.

Fissure volcanoes pour out low viscosity basaltic magma from fissure vents to form the extrusive rock basalt.

Composite or stratovolcanoes often have andesitic magma and typically form the extrusive rock andesite. Andesitic magma is composed of many gases and melted mantle rocks.

Cinder or scoria cones violently expel lava with high gas content, and due to the vapor bubbles in this mafic lava, the extrusive basalt scoria is formed.

Lava domes are formed by high viscosity lava that piles up, forming a dome shape. Domes typically solidify to form the rich in silica extrusive rock obsidian and sometimes dacite domes form the extrusive rock dacite, like in the case of Mount St. Helens.

Calderas are are volcanic depressions formed after an erupted volcano collapses. Resurgent calderas can refill with an eruption of rhyolitic magma to form the extrusive rock rhyolite like the Yellowstone Caldera.

Submarine volcanoes erupt on the ocean floor and produce the extrusive rock pumice. Pumice is a light-weight, glass with a vesicular texture that differs from scoria in its silicic composition and therefore floats.