The key difference between magma and lava lies upon the location. The formation of magma and lava results from rock superheating to a point where it becomes viscous. The main difference between magma and lava is that when this molten rock is within the Earth, it is known as magma but when magma reaches the surface and erupts from a volcano, it becomes lava. Let us now understand more about the difference between magma and lava by studying its roots.
What is Magma?
Magma is the molten or semi-molten rock, volatiles that is found beneath the surface of the Earth. This vicious or molten rock remains in the magma chamber beneath a volcano or solidifies underground to form an intrusion. Either the magma can fill up the cracks in rocks or comes out of volcanoes in eruptions. Certain mechanisms of magma generation in the mantle are decompression melting, heating, and lowering of the solidus.
What is Lava?
Magma reaching the surface erupting from a volcano is officially becomes lava. It is a semi-solid, burning hot substance. The study shows different kinds of lava depending on their thickness or viscosity.
Difference Between Magma and Lava
The important difference between magma and lava
|Definition||They’re the molten rock that’s still trapped underground.||When this molten rock comes to the surface and keeps flowing like a liquid. Its the Lava.|
|Temperature||700 °C to 1600 °C||700 to 1200 °C|
|Types||Basaltic, Andesitic, and Rhyolitic,||Pahoehoe flow, Aa flow, Blocky lava flow, and Pillow lava flow.|
|Composition||The mixture of minerals and small amounts of dissolved gases like carbon dioxide, sulfur.||Erupts with the slush of crystals, liquid, and bubbles. Contains chemical elements.|
|Cooling||Takes a longer time to cool down, as it is located underground.||Lava cools much quicker than Magma thus forms crystal sometimes.|
|Origin of Name||Ancient Greek.||Italian origin.|
After learning about the difference between Magma and Lava, it is important to know them in detail.
It is the molten or partially molten rock from beneath the earth’s surface. It cools to form igneous rocks. Magma forms due to high temperature and pressure. It usually consists of silicate liquid, although carbonate and sulfide melt occur as well. Rocks which forms due to solidification of magma beneath Earth’s surface are intrusive igneous. Magma is generated within Earth’s mantle, the thick layer between the crust and outer core.
On its way up toward the surface, magma can melt adjacent rock and forms metamorphic rocks.
Silicon dioxide (SiO2) is mainly found in magma. Along with its small proportions of aluminum oxide, iron, magnesium, calcium, sodium, potassium, titanium, manganese, phosphorus, and water is also there.
There are three basic types of magma,
1) Basaltic originating in the lower crust/upper mantle. It contains molten rock enriched in iron and magnesium and depleted in silica.
2) Rhyolitic originates in the oceanic crust. It erupts explosively, forming a frothy solidified magma called pumice along with ash.
3) Andesitic originates is the continental crust. It has fine-grained rocks that form when magma erupts and crystallized quickly on the surface.
Lava is actually the molten magma(molten rocks) expelled by a volcano during an eruption. It reaches the surface through a volcano vent. When first exuded from a volcanic vent, the hot lava is at temperatures ranging from 700 °C to 1,200 °C. When lava solidifies it is called “lava flow,” whereas the material that still contains molten rock is called an “active lava flow.” The major component of almost all types of lava has silicate minerals, mostly feldspars, olivine, pyroxenes, amphiboles, micas, and quartz.
There are four basic types of lava:
1) Pahoehoe lava flows are smooth, gently undulating, or broadly hummocky surfaces.
2) Aa lava flow resembles a very rough surface, covered with clinkers.
3) Block lava flow resembles as in having tops consisting largely of loose rubble, but the fragments are more regular in shape.
4) Pillow lava flow is a form of volcanic rock that results when low-viscosity magma such as basalt erupts underwater.
FAQs about Magma and Lava:
Q.1. What makes the magma come out of the chamber?
Ans- Magma forms from the partial melting of mantle rocks. When these melting rocks rise upward, gas molecules from the magma comes out of solution and form bubbles. These bubbles expand as they rise up. Pressure from these bubbles is stronger than the surrounding solid rock and creates fractures. Magma flows into these structures and gets to the surface.
Q.2. What is lava haze and why it is dangerous?
Ans- It occurs when molten lava flows into the ocean, reacting vigorously with seawater to create a different type of gas plume that results in hazy and noxious conditions at the place lava touches the sea.
This plume is dangerous to health. It is an irritating mixture of hydrochloric acid gas, steam, and tiny volcanic glass particles.