Explosive eruptions involved gas and high amounts of magma and tephra ejected into the sky. Effusive eruptions involve outpouring of basaltic lava without much of any explosive activity. The most extreme effusive volcanic eruption is the Hawaiian eruption, while the most explosive eruptions are the Plinian eruptions. Not all eruptions are emitted out of the top of the structure. Remember that Hawaiian eruptions happen along the rift zones and not necessarily from the top. There is a scale called the VEI or volcanic explosivity index, which is a scale that runs from 0 to 8. It is used for both modern and prehistoric eruptions in ways like we now use the Richter scale. It is not linear but logarithmic. This wide variation means that most eruptions today are between 0 and 2 on the VEI scale.
LAVA FLOWS AND PYROCLASTIC FLOWS Let's talk about the different type of lava flows and eruptions you'll see in more detail. You can see how they range from fairly mild to very dangerous eruptions. Magmatic eruptions are those that have some intensity and gas behind them. Tiny ones are seen as lava fountains and big ones are seen as high as 30 kilometers in the sky. This is bigger than the eruption that destroyed Pompeii in 79 AD when Mount Vesuvius erupted. Hawaiian eruptions are the effusive kind you see in Hawaii. These are relatively tame volcanoes that erupt with small volumes of basaltic lava. Most eruptions are not in the center of the volcano but erupt all over the volcano in rift zones. Because of the way these eruptions look, they are often called a curtain of fire when they erupt. Hawaiian eruptions last a long time. A volcanic area on Kilauea has been erupting for more than 35 years. Strombolian eruptions are named after Stromboli, which has been erupting for centuries now. These are mostly driven by gas bubbles that burst through the magma. These bubbles will burst and pop loudly with magma ejected in the air. You will hear these occasional blasts when the bubbles pop. Despite the sound, they do not cause a great deal of damage. Expect a few volcanic bombs to be ejected in the air as well.
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