1. MAGMA TYPES OF MAGMA WITH DETAIL

2. TYPES OF MAGMA Magma Introduction Types of Magma Classification on the basis of Silica % Classification on the basis of Formation Summary Table

3. INTRODUCTION Magma is extremely hot liquid and semi-liquid rock located under Earth’s surface. Earth has a layered structure that consists of the inner core, outer core, mantle, and crust. Much of the planet’s mantle consists of magma. This magma can push through holes or cracks in the crust, causing a volcanic eruption. When magma flows or erupts onto Earth’s surface, it is called lava. Like solid rock, magma is a mixture of minerals. It also contains small amounts of dissolved gases such as water vapor, carbon dioxide, and sulfur. The high temperatures and pressure under Earth’s crust keep magma in its fluid state.

4. MAGMA FORMATION :-

5. TYPES OF MAGMA Why there are so many different types of magma ? Because it depends on the source, how it interacts with its surroundings (assimilation), and whether crystals sink as they form (partial melting and magma mixing) also on the formation of magma and silica content.

6. CLASSIFICATION ON THE BASIS OF FORMATION OF MAGMA Primitive Magma They are unmodified magmas that form through anataxis ( melting of mantle rocks that have not been changed In composition since they are formed. The leucosomes of migmatites are examples of these melts.

7. PRIMARY MAGMA This magma are chemically unchanged melt derived from any kind of pre-existing rocks. All primitive magma are primary but most primary magma that yield modern rocks is not primitive. Formed at depth and not subsequently modified by Fractional Crystallization or Assimilation. When a rock melts, the liquid is a primary melt. Primary melts have not undergone any differentiation and represent the starting composition of a magma.

8. IMPORTANCE :- By finding the primary magma composition of a magma series it is possible to model the composition of the mantle from which a melt was formed, which is important in understanding evolution of the mantle.. In nature it is rare to find primary melts.

9. PARENTAL MAGMA Where it is impossible to find the primitive or primary magma composition, it is often useful to attempt to identify a parental melt. A parental melt is a magma composition from which the observed range of magma chemistries has been derived by the processes of igneous differentiation. It need not be a primitive melt. For instance, a series of basalt flows are assumed to be related to one another. A composition from which they could reasonably be produced by fractional crystallization is termed a parental melt. Fractional crystallization models would be produced to test the hypothesis that they share a common parental melt.

10. BASIC TYPES OF MAGMA( ON THE BASIS OF SILICA %) Andesitic Magma Basaltic Magma Felsic Magma Intermediate Magma Mafic Magma Rhyolitic Magma Ultramafic Magma

11. ANDESITIC MAGMA When it comes to its features, heat, fluidity, and gas content, andesitic magma is considered to be in the middle. It has a silica content of roughly 55% to 65%, and its sodium, potassium, iron, calcium, and magnesium contents are considered average. After andesitic magma cools it becomes andesite rock.

12. CONTI…. The magma is slightly explosive, although not as vicious as other types of volcanoes, and it is found in small- to medium-sized earthquakes because of the faults that result from its explosive eruptions. A good example of andesitic magma is the eruption of Oregon’s Mount St. Helens. Andesitic magma has a mean temperature that is between 1471 and 1832 Fahrenheit.

13. BASALTIC MAGMA With a 45-55% accumulation of silica, basaltic magma is high in minerals such as magnesium, iron, and calcium, while its potassium and sodium contents are fairly low. Basaltic magma has a mean temperature that is between 1832 and 2192 Fahrenheit, although this estimate is based mostly on limited field operations and measurements within the lab. When basaltic magma changes to rock

14. CONTI…. It is very difficult to get close to basaltic magma, which is why exact measures of this type of magma are not possible. Basaltic magma is also more fluid than any other type of magma, though it is nowhere near the fluidity of water. In fact, basaltic magma is roughly 10,000 to 100,000 times less fluid than water. It also has a very low amount of gas and is found in “hot spots” throughout the earth, including Hawaii. Basaltic magma becomes basalt rock once it cools.

15. RHYOLITIC MAGMA Rhyolitic magma is formed by a combination of basaltic magma and another material that is siliceous. It can also be formed by melting parts of the earth’s sialic layer. The magma is made up of rhyolite, which has a high content of silica and is very gelatinous. Its flow is similar to that of toothpaste when it is coming out of its tube, and it often piles up and forms domes of lava.

16. CONTI…. Rhyolitic magma is sometimes rich in gas, and when this is so, it can spew viciously into the air. In these instances, pumice is formed, which is solid magma that is lightweight and light in color. In other instances, rhyolite lava is very porous and can form a glass-like material that is dark in color, called obsidian. In fact, rhyolite is similar to granite when it comes to volcanoes. When it changes into rock

17. MAGMA TYPES AND THEIR ROCKS

18. FELSIC MAGMA Of all the types of magma that exist, felsic magma has the most silica in it. The percentage of silica in felsic magma is between 65% and 70%, and, because of this, it also has the highest viscosity (gooiness) and gas content. Of course, it also has low mean temperatures compared to other types of magma, with numbers that range from 1202 and 1472 Fahrenheit. Felsic magma is very thick and gooey, which means that it sometimes gets gas bubbles in the magma chamber of the volcano.

19. CONTI… These bubbles can cause extremely dangerous eruptions that cause lava to spew into the air and eventually turn into rhyolite and dacite rock. Felsic magma is similar to intermediate magma, as both have sticky, thick lava that spews out in a rough manner and causes rock formations later on. Its magnesium, calcium, and iron contents are low, but it is high in both sodium and potassium.

20. CONTI… The magma also has a lot of unstable gases and melted rock, and it can form very large calderas, which are depressions or craters found on larger volcanoes. You can see a large caldera in Yellowstone Park, and these craters are usually formed when the magma chamber of a volcano becomes empty.

21. INTERMEDIATE MAGMA Although it doesn’t have a silica content that is as high as felsic magma, intermediate magma is roughly 60% silica, so it still contains a lot of silica. Like felsic magma, however, intermediate magma is very thick and very gooey, and its mean temperature is usually between 1472 to 1832 Fahrenheit, making it much hotter than felsic magma. Intermediate magma tends to build up pressure when it is below the surface of the earth, and, afterwards, it is released as lava

22. CONTI…. Intermediate magma often transforms into andesite because of its heat content, and these are rocks that get their name from the Andes Mountains in South America.

23. MAFIC MAGMA Made up of only 50% silica, the silica content of mafic magma is considered very low. However, it does contain a lot of magnesium and iron, along with a low gas content and not very much gooiness. Mafic magma has a very high mean temperature – between 1832 and 3632 Fahrenheit – which is one of the reasons that its viscosity is a little lower than other types of magma.

24. CONTI…. Of course, this factor also allows it to be one of the most fluid types of magma, and it both moves very quickly and erupts in a non-aggressive manner. Its lava eventually cools down into a rock called basalt, which is dark-colored and very heavy. The color is due to the amount of magnesium and iron in the magma, because both of these minerals are very dark in color.

25. CONTI… In addition, basalt is a very common rock found in the earth’s crust, and it is also found in the volcanic islands developed by hot spots. The islands found in Hawaii are a perfect example of the results of eruptions made up of mafic magma.

26. TYPES OF MAGMA CONTI…..

27. COMPOSITION

28. ULTRAMAFIC MAGMA Also known as komatiite magma, this type of magma is not found anywhere today because of the planet’s cooler temperatures. When this type of magma was still around, it reached temperatures of approximately 2900 Fahrenheit. Ultramafic magma burned very hot but flowed very fast; in fact, it would flow down a volcano almost as quickly as water would.

29. PHYSICAL AND CHEMICAL CHARACTERISTICS OF MAGMAS

30. MAGMA OF IGNEOUS ROCKS AND THEIR MINERALS

31. SUMMARY TABLE OF BASIC THREE TYPES OF MAGMA

32. THANKS FOR YOUR ATTENTION