What are 2 extrusive volcanic features?

Dome volcano – a volcano with steep sides that is formed by thick rhyolitic lava flows. Caldera – a large crater caused by the violent explosion of a volcano that collapses into a depression. Lava plateau – a wide, flat landform that results from repeated non-explosive eruptions of lava that spread over a large area.

What is a feature of an extrusive igneous rock?

Extrusive igneous rocks form after lava cools above the surface. Extrusive igneous rocks cool much more rapidly than intrusive rocks. There is little time for crystals to form, so extrusive igneous rocks have tiny crystals (Figure below). [Figure5] Cooled lava forms basalt with no visible crystals.

What are the intrusive and extrusive features of volcanoes?

Intrusive- magma cools, crystallises and solidifies into igneous rocks below the earths surface. Extrusive- magma surfaces as lava and cools, crystallises and solidifies through contact with air (fast) or the sea (rapid) into igneous rocks above the earths surface.

What are extrusive landforms give examples?

Extrusive landforms that are formed due to the eruption of…

• Conical hill: A cone shaped hill is a typical example of an extrusive landform.
• Cone: A cone is formed when rock materials and debris are thrown away by a volcanic eruption.
• Crater: It is a bowl shaped depression formed at the mouth of a volcano.

What are three extrusive volcanic features?

Volcanic Features and Landforms

• Craters. Craters form as the result of explosive eruptive activity at a volcanic vent where rock, magma, and other material is ejected leaving a conical void.
• Calderas.
• Diatremes and Maars.
• Lava Flows.
• Lava Tubes.
• Fumaroles.
• Geothermal Features.

What are the volcanic features?

Landform-scale, volcanic geomorphologic features include lava flows and related features (diverse types of scarps, levees, and lava flow surface features); lahars, calderas, the diverse types of cones and related rims, necks, domes, tubes, trenches, fissures and scarps.

What is an example of extrusive rock?

There are two basic types: 1) intrusive igneous rocks such as diorite, gabbro, granite and pegmatite that solidify below the Earth’s surface; and 2) extrusive igneous rocks such as andesite, basalt, obsidian, pumice, rhyolite and scoria that solidify on or above the Earth’s surface.

What are three volcanic features?

What are intrusive features?

When magma cools and solidifies in these spaces, Intrusive or plutonic igneous rocks are formed deep beneath the Earth’s surface. Intrusive features like stocks, laccoliths, sills, and dikes are formed. The mass of cooling magma is called a pluton, and the rock around is known as country rock.

What are the three types of volcanic landforms?

There are three types of volcanoes: cinder cones (also called spatter cones), composite volcanoes (also called stratovolcanoes), and shield volcanoes. Figure 11.22 illustrates the size and shape differences amongst these volcanoes. Shield volcanoes, which get their name from their broad rounded shape, are the largest.

What is intrusive volcanic features?

Intrusive Volcanic Features. INTRUSIVE volcanic features are intruded into the lithosphere or rock, there they cool and solidify into rocks and are later exposed at the land surface as erosion and weathering DENUDE the land downwards.

What is the most common type of intrusive rock?

Granite
Granite is the most common intrusive rock on the continents; gabbro is the most common intrusive rock in oceanic crust.

How are intrusive and extrusive volcanic landforms different?

Volcanic Landforms. Volcanic landforms are divided into extrusive and intrusive landforms based on weather magma cools within the crust or above the crust. Rocks formed by cooling of magma within the crust are called ‘Plutonic rocks’.

What are the intrusive and extrusive features of magma?

Intrusive- magma cools, crystallises and solidifies into igneous rocks below the earths surface. Slow cooling results in larger crystals e.g granite and dolerite. Extrusive- magma surfaces as lava and cools, crystallises and solidifies through contact with air (fast) or the sea (rapid) into igneous rocks above the earths surface.

Which is an example of an extrusive feature?

Extrusive- magma surfaces as lava and cools, crystallises and solidifies through contact with air (fast) or the sea (rapid) into igneous rocks above the earths surface. Quicker cooling results in finer crystals e.g basalt.

How are volcanic features formed on the surface?

Some features are formed on the surface and are known as extrusive volcanic features. Others are formed below the surface and are known as intrusive volcanic features. The CSEC / CXC syllabus requires you to know the following extrusive volcanic features: