What is the difference between basaltic andesitic and rhyolitic magma?
Viscosity is most affected by temperature and silica content. There are three common types of magma which are as follows from high temperature to low temperature: basaltic (50% SiO2); andesitic (60% SiO2); and rhyolitic (70% SiO2). Basaltic magma has a low viscosity whereas rhyolitic magma has a high viscosity.
What are 3 types of magma?
Different Types of Magma
- Basaltic Magma. Basaltic magma is made up of 45 to 55 percent silica. …
- Andesitic Magma. Andesitic magma is the "middle" magma in terms of heat; fluidity, or speed of flow; and gas content. …
- Felsic Magma. …
- Ultramafic Magma.
What are the 4 types of magma?
Because many of the properties of a magma (such as its viscosity and temperature) are observed to correlate with silica content, silicate magmas are divided into four chemical types based on silica content: felsic, intermediate, mafic, and ultramafic.
Is magma classified as basaltic andesitic or rhyolitic?
Viscosity of Magmas
| Summary Table | ||
|---|---|---|
| Magma Type | Solidified Rock | Viscosity |
| Basaltic | Basalt | Low |
| Andesitic | Andesite | Intermediate |
| Rhyolitic | Rhyolite | High |
Sep 14, 2015
What is the difference between andesitic and basaltic?
Andesitic lava is an example of a high viscosity lava whereas balastic lava has a low viscosity, so is more runny. High silica content in the andesitic lava contributes to causing this high viscosity and low silica content in the basaltic lava means it is of a lower viscosity.
What is the difference between basalt and rhyolite?
Rhyolite is a sticky or viscous lava that usually does not flow very far from the place where it is erupted. In contrast, basalt is a volcanic rock that contains relatively little silica and abundant iron and magnesium, so phenocrysts of olivine and pyroxene are common. Basalt is usually black to dark brown in color.
What is rhyolitic magma?
Rhyolitic lavas are viscous and tend to form thick blocky lava flows or steep-sided piles of lava called lava domes. Rhyolite magmas tend to erupt explosively, commonly also producing abundant ash and pumice.
What is andesitic magma?
Andesite is a gray to black volcanic rock with between about 52 and 63 weight percent silica (SiO2). Andesites contain crystals composed primarily of plagioclase feldspar and one or more of the minerals pyroxene (clinopyroxene and orthopyroxene) and lesser amounts of hornblende.
What are the 3 ways magma can form?
There are three principal ways rock behavior crosses to the right of the green solidus line to create molten magma: 1) decompression melting caused by lowering the pressure, 2) flux melting caused by adding volatiles (see more below), and 3) heat-induced melting caused by increasing the temperature.
What are the main difference between basaltic and andesitic magma?
Basaltic magma is high in iron, magnesium, and calcium but low in potassium and sodium. It ranges in temperature from about 1000oC to 1200oC (1832oF to 2192oF). Andesitic magma has moderate amounts of these minerals, with a temperature range from about 800oC to 1000oC (1472oF to 1832oF).
What type of igneous rock is andesite?
extrusive igneous Andesite is a fine-grained, extrusive igneous or volcanic rock. It is dark grey and made up of equal amounts of light and dark minerals, although the crystals are too small to be seen without a magnifier. Occasionally andesite may contain some larger crystals.
Is rhyolite extrusive or intrusive?
extrusive igneous rock rhyolite, extrusive igneous rock that is the volcanic equivalent of granite.
What is basaltic magma?
Basaltic (or mafic) magma predominates in nonexplosive volcanic eruptions. It is a high-temperature magma (1,200 °C (about 2,200 °F)) characterized by flowing lava, and it is made up of about 45–55 percent silica (SiO2) by weight.
How is rhyolitic magma formed?
Rhyolitic magma forms as a result of wet melting of continental crust. Rhyolites are rocks that contain water and minerals that contain water, such as biotite. The continental crust must be heated above the normal geothermal gradient in order to melt.
What type of volcano has rhyolitic magma?
stratovolcanoes Shield volcanoes are formed by basaltic magma, typically above a mantle plume, whereas the stratovolcanoes (sometimes referred to as composite volcanoes) are formed by andesitic/rhyolitic magma.
What is rhyolite rock?
rhyolite, extrusive igneous rock that is the volcanic equivalent of granite. Most rhyolites are porphyritic, indicating that crystallization began prior to extrusion.
What is the difference between basalt and andesite?
Both lavas are formed at different plate boundaries which is why they have different silica contents: the basaltic lava forms from the hot mantle material at constructive plate boundaries and hotspots whereas the andesitic lava forms at destructive plate boundaries from melting crust.
Is basalt intrusive or extrusive?
extrusive igneous basalt, extrusive igneous (volcanic) rock that is low in silica content, dark in colour, and comparatively rich in iron and magnesium.
What is andesitic lava?
Andesite is a gray to black volcanic rock with between about 52 and 63 weight percent silica (SiO2). Andesites contain crystals composed primarily of plagioclase feldspar and one or more of the minerals pyroxene (clinopyroxene and orthopyroxene) and lesser amounts of hornblende.
What is an andesitic volcano?
Andesite is a gray to black volcanic rock with between about 52 and 63 weight percent silica (SiO2). Andesites contain crystals composed primarily of plagioclase feldspar and one or more of the minerals pyroxene (clinopyroxene and orthopyroxene) and lesser amounts of hornblende.
What is basaltic volcano?
Basaltic volcanoes are characterized by persistent periods of activity ranging from effusive lava flows to explosive eruptions with variable intensity (i.e., lava fountains to high-intensity, short-lasting paroxysmal events), each posing different types of potential threats to the local population.
What is basalt rocks?
basalt, extrusive igneous (volcanic) rock that is low in silica content, dark in colour, and comparatively rich in iron and magnesium. basalt.
What kind of rock is basalt?
volcanic rock Basalt is a hard, black volcanic rock. Basalt is the most common rock type in the Earth's crust. Depending on how it is erupted, basalt can be hard and massive (Figure 1) or crumbly and full of bubbles (Figure 2).
Is rhyolite intrusive or extrusive?
extrusive igneous rock rhyolite, extrusive igneous rock that is the volcanic equivalent of granite.
What is rhyolitic lava?
Rhyolitic lavas are viscous and tend to form thick blocky lava flows or steep-sided piles of lava called lava domes. Rhyolite magmas tend to erupt explosively, commonly also producing abundant ash and pumice.
What is basaltic lava?
Basaltic lava is another term for mafic lava. Mafic lava is molten rock that is enriched in iron and magnesium and low in silica. When mafic lava cools on the earth's surface, it forms basalt, which is why mafic lava is commonly called 'basaltic lava.
What type of rock is rhyolite?
rhyolite, extrusive igneous rock that is the volcanic equivalent of granite. Most rhyolites are porphyritic, indicating that crystallization began prior to extrusion.