Magma vs Lava – Difference Between Magma and Lava
The difference between lava and magma is that magma is the term used for molten rock that resides underground whereas lava is the term used to describe molten rock that breaks through to the surface.
They are both incredibly similar to one another, but their locational difference is ultimately how we can tell lava vs magma apart. There are a few other areas that separate them too, as we will highlight over the course of this post. If you are ready to find out more, then let’s dive straight into the definition of magma.
Definition of Magma – So What Is Magma?
The magma definition is a liquified combination of molten rock and gases located on the inside of a volcano.
It can be really challenging to determine the difference between lava and magma when we look at their composition alone because ultimately they are both formed out of molten rock and natural gases and both appear in liquid form.
There are luckily several different types or varieties of both lava and magma that we can use to tell them apart, but first we will focus on the most obvious difference, which is their individual location within the composition of a volcanic structure.
When people are searching for an answer to the question what is magma, this is often due to the belief that it is a completely separate and altogether different entity from lava. While this is partially true (mainly due to the different varieties of magma not being labelled in the same way as lava types), magma and lava are one and the same in practical reality. What sets them apart is purely their location.
Magma is located deep within the heart of a volcano in something known as the magma chamber. You could view this chamber as being the beating heart of a volcano. This is where all of the activity emanates from. The liquid rock and gas combination (magma) contained in the chamber then travels upwards due to pressure before being expelled into the air from the mouth of the volcano.
This pressure arises because of something known as tectonic plates gliding over each other. This creates friction that then leads to heat, which then leads to the creation of magma and pressure at the same time due to the buildup of gases during the heat exchange process.
The earth then naturally responds by creating an exit for the buildup to escape from in the form of a volcanic structure. In reality, a volcano is little more than a pressure cooker and a safety release valve to ensure that the pressure from the tectonic plate movement does not stay within the earth’s foundation and create some kind of implosion or collapse.
Magma is the precursor to (comes before) lava. So, the magma in the center of a volcano is the product of tectonic plate movement and friction, and the lava is the earth’s natural way of releasing the pressure being emitted from the heat of the magma combined with the kinetic movement of the tectonic plates. Magma flows; then lava follows.
Naturally, the lava release needs to be emitted upwards. It cannot go downwards because it has nowhere viable to travel in this direction. The laws of physics dictate that the only way that this heat energy can travel is up.
There are three common magma varieties that form depending on the unique mineral or chemical composition of the magma. This composition is largely dictated by the location of the magma or the tectonic plates that formed the magma and the structure of the tectonic plates.
Here are the three different varieties.
- Basaltic magma: Basaltic magma is formed as a result of high levels of magnesium, calcium, and iron. Low amounts of sodium and potassium are present, however. The typical temperature range for this type of magma is 1832 degrees Fahrenheit to 2192 degrees Fahrenheit.
- Rhyolitic magma: Sodium and potassium are present in very high amounts in this variety of magma. In contrast to basaltic magma, magnesium, calcium, and iron levels are low. The typical temperature range for this magma variety is 1202 degrees Fahrenheit to 1472 degrees Fahrenheit.
- Andesitic magma: This is a well-balanced magma variety that features sodium, calcium, potassium, magnesium, and iron at moderate levels. The typical temperature range for this magma type is 1472 degrees Fahrenheit to 1832 degrees Fahrenheit.
When we dive into the question what is the difference between magma and lava further in the next section by analyzing the specific definition of lava, you will see a significant difference in the classification of lava varieties as their names are entirely dissimilar to the different magma varieties.
Definition of Lava – So What Is Lava?
The lava definition is a combination of gases and molten rock that comes out of the mouth of a volcano.
Immediately, for anyone asking the question what is lava, we have a clear giveaway in the form of the external location of lava. We know that magma forms and stays within something known as the magma chamber, which is inside the core of a volcano. The fact that lava actually comes out of a volcano and reaches the exterior shows us that it is completely different.
Compositionally, the variations between magma vs lava are negligible because they are formed out of exactly the same material. With this in mind, you might be wondering why we mentioned that lava actually has several different classifications of its own.
Well, these classifications are based on the characteristics of the lava as opposed to what it is made out of. Consider these classifications of lava.
- A’a (a thick, viscous lava that moves incredibly slowly down the side of a volcano and once cooled, forms a solid structure that is hard to break).
- Pahoehoe (a free-flowing lava with a small degree of viscosity).
- Pillow lava (a type of lava that appears when an underwater volcano erupts).
Even though we can separate lava vs magma based on these unique classifications, it is worth mentioning that what ultimately determines the characteristics of lava (and therefore its unique classification) is its composition. Its composition will of course be determined by the type of magma that it is derived from.
To help answer the question what is the difference between magma and lava further, we are going to provide you with a quick reference table in the next section that visually highlights their main variations.
What Is the Main Difference Between Magma vs Lava?
The following table showcases every major difference between magma and lava in a format that you can come back to for a quick refresh anytime you get stuck with this subject.
|Definition||Molten rock and gas that appears on the surface of the earth||Molten rock and gas that appears on the inside of the earth|
|Temperature range||1300 – 2200 degrees Fahrenheit||1300 – 2400 degrees Fahrenheit|
|Cooling period||Significantly quicker than magma||Takes much longer to cool than lava|
|Location||On the outside of a volcano||On the inside of a volcano|
|Classifications||A’a, pahoehoe, pillow||Basaltic, rhyolitic, andesitic|
All of the major variations between magma vs lava appear above and form the backbone of the comparison between the two.
Magma vs Lava – FAQ
Here are the most frequently asked questions about these two natural volcanic substances.
Q: So, what is the difference between magma and lava?
A: The primary variation between these two volcanic substances is that magma is located on the inside of a volcano, whereas lava is located on the outside of a volcano.
Q: When does magma become lava?
A: Magma becomes lava at the exact point where it exits the volcano structure and reaches the earth’s surface.
Q: Is lava hotter than the sun?
A: No, the sun has a surface temperature of 10,000 degrees Fahrenheit, meaning that the sun is significantly hotter.
Q: Why is magma sometimes called lava?
A: The word magma has Italian origins and basically means “thick and pasty,” which is precisely what magma is like when it is inside the earth. Lava also has Italian origins, but it means “to slide,” which is exactly what lava does when it exits a volcano and reaches the surface of the earth.
Q: What are the similarities between lava and magma?
A: Magma and lava are both made out of molten rock and gases. Their main difference is simply their location. One is found inside the earth, and one is found on the surface of the earth.
Q: I’m trying to understand what is the difference between lava and magma and how they are made? Do they have different properties?
A: Lava is classified based on its physical characteristics, which are determined by the type of magma that creates it, whereas magma is classified based on its mineral composition.
Q: What is currently the hottest object in the known universe?
A: There is a star known as the “Dead Star” in the middle of the Red Spider Nebula that has a surface temperature of 250,000 degrees Fahrenheit. This is currently the hottest known object in the universe.
So What’s the Difference Between Lava and Magma? – Conclusion
Finally, you should now be able to easily summarize the difference between magma and lava based on their different definitions and the classifications they have.
If you ever find yourself asking the question what’s the difference between magma and lava again in the future, just remember that in summary, lava is found on the outside of a volcano whereas magma is found on the inside of a volcano.
If you ever need to refresh your memory on this subject again, simply take a look over the quick reference table we created for you, and it will help you to separate them in no time.