0
Felsic magmas have higher silica content, making them more viscous and prone to trapping gas bubbles. When trapped gas pressure builds up, it can lead to a more explosive eruption. Mafic magmas, on the other hand, have lower silica content and are less viscous, allowing gas to escape more easily, resulting in less explosive eruptions.
What else can I help you with?
Does mafic magma explode?
Mafic magmas generally have lower viscosity and gas content compared to felsic magmas, so they tend to flow more easily rather than explode. However, in certain conditions where gas build-up is high and pressure is released rapidly, mafic magma may still explode, but it is less common than with felsic magmas.
What is mafic lava like?
Mafic lava is low in silica and high in iron and magnesium, which makes it less viscous and more fluid compared to felsic lava. It tends to flow easily and often forms basaltic rocks when it cools. Mafic lava eruptions typically result in gentle, effusive lava flows rather than explosive eruptions.
Does rhyolite have a more mafic composition than basalt?
Rhyolite is not a mafic rock, but a felsic rock, high in silicates, and similar to granite in composition.
What is the lithosphere made of mafic or felsic?
Its made up of both. Oceanic crust is mostly mafic magma (basalt) and continental crust is mafic and felsic. The lithosphere also contains the upper portion of the upper mantle which is mostly mafic. The earths crust is 60% Si02 (silicates). Felsic rocks are much more silicate heavy than mafic. So one would assume that the crust is more felsic than mafic. That's just my conceptual thought process so don't take me on my word. Then again, the lithosphere also contains the upper mantle which is heavily mafic. So maybe the lithosphere in total is more mafic? Basically just typing thoughts down as they enter my brain. Answer I know for certain- Lithosphere is mafic and felsic.
Is Tuff mafic or felsic?
Pumice is more related to a textural feature, rather than a compositional attribute. For example, pumice originates when there are enough dissolved gases in the magma, such that when it is ejected from the volcano, the depressurization of the dissolved gases causes a rapid expansion as the gases exsolve (just like when you open a pop - the gases are initially under pressure, and you release that pressure by opening the can or bottle). The rapid change in temperature, from hundreds to thousands of degrees to the temperature of of the surrounding environment, causes a rapid cooling effect, whereby the expanding gases are frozen in place. These two factors are what give pumice its distinctive texture and ability to float when placed in water, as opposed to other volcanic rocks (such as scoria).Whether or not the pumice is felsic (light in color) or mafic (dark in color) depends on its chemical composition and therefore, pumice can be both felsic or mafic depending on its parental magma.General classification as to whether a rock is felsic or mafic is with regards to the silicate content of the rock as follows:felsic < 69% SiO2Intermediate Felsic 63 - 69% SiO2Intermediate 52- 63% SiO2Mafic < 52% SiO2Ultra Mafic < SiO2This said, felsic pumice (white or light tan brown colors) are more common to find than mafic pumice.
What eruption is worse mafic or silicic?
Eruptions involcing silicic or felsic magma are generally the worst. Eruptions of mafic material are usually effusive or only mildly explosive, producing cinders or lava flows. Eruptions of felsic material often produce large ash clouds and deadly pyroclastic flows.
Does Krakatoa have felsic magma or mafic?
Krakatoa volcano typically has mafic magma, which is low in silica content and high in magnesium and iron. This type of magma tends to be more fluid and can lead to explosive eruptions due to the rapid release of gases.
Does mafic magma explode?
Mafic magmas generally have lower viscosity and gas content compared to felsic magmas, so they tend to flow more easily rather than explode. However, in certain conditions where gas build-up is high and pressure is released rapidly, mafic magma may still explode, but it is less common than with felsic magmas.
Do composite cone volcanoes have mafic lava?
They can. Composite volcanoes vary in what they erupt. Many composite volcanoes are composed of a mixture of mafic, felsic, and intermediate rock. However, in most cases intermediated or felsic rock predominates.
What is mafic lava like?
Mafic lava is low in silica and high in iron and magnesium, which makes it less viscous and more fluid compared to felsic lava. It tends to flow easily and often forms basaltic rocks when it cools. Mafic lava eruptions typically result in gentle, effusive lava flows rather than explosive eruptions.
Does rhyolite have a more mafic composition than basalt?
Rhyolite is not a mafic rock, but a felsic rock, high in silicates, and similar to granite in composition.
Is mauna loa mafic or felsic?
The 1980 eruption of Mount St. Helens produced dacite, which has an intermediate-felsic composition.
What type of lava does mauna loa have felsic-rhyolitic intermediate-andesitic mafic-basaltic?
Mauna Loa exhibits non-explosive eruptions (like many in the Hawaiian islands) in the form of low viscosity (more fluid) lava due to poor silica content.
How does mafic lava turn into felsic lava?
Mafic lava, before cooling, has a low viscosity, in comparison to felsic lava, due to the lower silica content in mafic magma. Water and other volatiles can more easily and gradually escape from mafic lava, so eruptions of volcanoes made of mafic lavas are less explosively violent than felsic lava eruptions. Most mafic lava volcanoes are oceanic volcanoes, like Hawaii.Felsic is a term used in geology to refer to silicate minerals, magmas, and rocks which are enriched in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium. The term combines the words "feldspar" and "silica." Felsic minerals are usually light in color and have specific gravities less than 3. Common felsic minerals include quartz, muscovite, orthoclase, and the sodium-rich plagioclase feldspars. The most common felsic rock is granite. On the opposite side of the rock spectrum are the iron and magnesium-rich mafic and ultramafic minerals and rocks.There are a few means by which felsic magma can be generated from mafic magma. Felsic materials have lower melting points than mafic materials and so will tend to melt first during partial melting. This can shift composition to something more felsic. Another process is called fractional crystalization. Here, more mafic material crystallizes and settles out of a magma chamber, making the remaining molten material more felsic. Finally, as mafic magma moves though continental crust, which is generally felsic in composition, it incorporates some of the rock and becomes more felsic.
Are pyroclastic flows felsic or mafic?
Pyroclastic flows can be of any composition, but are more commonly felsic or intermediate.
Why silica rich magma is more dangerous than iron rich magma?
The silica-rich magma, also called felsic magma, is more viscous than iron-rich or mafic magma. This means resists flow more (just as syrup is more viscous than water). The high viscosity means that the felsic magma can trap more gasses, leading to explosive eruptions, rather than effusive ones.
What is the difference in density in mafic rocks in relation to felsic rocks?
Mafic rocks, such as those found in the oceanic crust, are more dense than the felsic rocks found in the continental crust.
