Explosive eruptions are favored by high gas content and high viscosity (andesitic to rhyolitic magmas). Explosive bursting of bubbles will fragment the magma into clots of liquid that will cool as they fall through the air.

Magmas can vary widely in composition, but in general they are made up of only eight elements; in order of importance: oxygen, silicon, aluminum, iron, calcium, sodium, magnesium, and potassium (Figure 3.6).

Oxygen, the most abundant element in magma, comprises a little less than half the total, followed by silicon at just over one-quarter. The remaining elements make up the other one-quarter. Magmas derived from crustal material are dominated by oxygen, silicon, aluminum, sodium, and potassium.

Magma is formed by both wet and dry melting processes. By melting different parts of the layers of the earth, basaltic, rhyolitic and andesitic magma will be formed.

Several interrelated physical properties determine the characteristics of magma, including chemical composition, viscosity, dissolved gases, and temperature. Learn about magma and the role its components play in its rate of flow and overall explosiveness during volcanic eruptions.

Felsic magma has the highest silica content of all magma types, between 65-70%. As a result, felsic magma also has the highest gas content and viscosity, and lowest mean temperatures, between 650o and 800o Celsius (1202o and 1472o Fahrenheit).

Basaltic magma is high in iron, magnesium, and calcium but low in potassium and sodium.

Explosive eruptions are favored by high gas content & high viscosity magmas (andesitic to rhyolitic magmas). The explosive bursting of bubbles fragments the magma into clots of liquid that cool as they fall through the air. These solid particles become pyroclasts or volcanic ash.

Composite volcanoes are some of the most dangerous volcanoes on the planet. They tend to occur along oceanic-to-oceanic or oceanic-to-continental boundaries because of subduction zones. They tend to be made of felsic to intermediate rock and the viscosity of the lava means that eruptions tend to be explosive.

Scientists use the term magma for molten rock that is underground and lava for molten rock that breaks through the Earth’s surface.

The most common way to divide lava flows into distinct types is following: Pahoehoe lava flow, Aa lava flow, Blocky lava flow, and also Pillow lava flow. Sometimes Turbulent lava flow is also added, but the latter is only of theoretical interest to scientist because we will not see that type of lava flow in the nature.

Hardly any human has been killed by a lava flow – they are relatively slow-moving and while they can destroy huge tracks of farming land, houses, roads, and infrastructure, even on the most active volcanoes, you can outrun all the lava flows.

The lavas of different volcanoes, when cooled and hardened, differ much in their appearance and composition. If a rhyolite lava-stream cools quickly, it can quickly freeze into a black glassy substance called obsidian.

When lava reaches the surface of the Earth through volcanoes or through great fissures the rocks that are formed from the lava cooling and hardening are called extrusive igneous rocks. Some of the more common types of extrusive igneous rocks are lava rocks, cinders, pumice, obsidian, and volcanic ash and dust.

While lava can be as hot as 2200 F, some flames can be much hotter, such as 3600 F or more, while a candle flame can be as low as 1800 F. Lava is hotter than a typical wood or coal-buring fire, but some flames, such as that of an acetylene torch, is hotter than lava.

To put it simply, a diamond cannot melt in lava, because the melting point of a diamond is around 4500 °C (at a pressure of 100 kilobars) and lava can only be as hot as about 1200 °C.

Since it tends to flow more as a thick liquid it can pour uphill as well as downhill and can create a huge variety of interesting shapes. If pahoehoe lava flows over a fairly flat ground it will coat the ground much like a parking lot – with a thick, smooth, flat coating of lava.

Lava is molten stone that has a temperature range of 1,300 to 2,200 F. It can also range in consistency from extreme liquid, like water to a thick bubbling oatmeal consistency. If you touch it, it will feel like Hell for the few seconds it will take to vaporize your hand..

Scientists usually use the color of the lava as a rough indicator of how hot it is, with red being “cool” (about 1,472 °F), orange being slightly warmer (about 1,472–1,832 °F), and yellow being the hottest (from 1,832–2,192 °F), according to the USGS.

Freshly cooled lava can have smell and taste from roasted trees and other organics that it burned up. Consider that Hawaiian lava cooled in the ocean might taste salty unless the salt was washed away with rain water. Cool lava is darn close to pottery (ceramics) with hardly any taste.

Most lava is very hot—about 2,000 degrees Fahrenheit. At those temperatures, a human would probably burst into flames and either get extremely serious burns or die. Unlike a lake, people won’t immediately sink into lava.

In addition to regular menu items like café latte, cakes and sandwiches you can order edible lava at Bræðraborg Café in the town of Ísafjörður in the Westfjords. The pieces look exactly like lava, and they even feel like lava in your hand, so people don’t believe they are actually edible until they bite into them!”

If you tried to eat it, you would suffer burns before you ever got it in your mouth. If it was poured into your open mouth by someone else, it would cause third degree burns. You wouldn’t be able to swallow it — lava is molten rock, and as such, is extraordinarily dense and viscous.

While your lungs would almost undoubtedly be irrevocably charred from the hot air above the lava (assuming relatively static air conditions over the lava), it takes about 80 seconds for the average human to fall unconscious from lack of oxygen, and I highly doubt your body will last that long.

High enough heat will indeed burn bone. Anything living that has bones would certainly be destroyed by lava.

While exploring an active volcano, Dante Lopardo decided to urinate on some molten rock, which has a temperature of about 700°C. As seen in the video Lopardo took, the pee instantly vaporizes as it hits the liquid rock and the lava sizzles. It also leaves something of a charred black mark after sizzling off.

If you fall into a deep volcano you will survive with only psychological trauma 23.7 seconds followed by sudden loss of consciousness.

Despite their ubiquity all over Hawaii’s Big Island, it’s rare for someone to actually fall into a lava tube, experts have said. But it can happen. And on Monday, police said it happened to an elderly man — in his own backyard. He was transported to the hospital, where he was pronounced dead, police said.

Volcanic eruptions