QA #3

Q How much lava, exactly, erupts from an exploding volcano? Is there much variability?

A Yes, there is tons of variability in the amount of lava that shoots out of a volcano (or system of volcanoes) over its lifetime. For example, one eruption (or, more likely, a series of eruptions) that happened roughly 250 million years ago in present-day Siberia produced enough lava to cover a surface area equal to that of western Europe, or about 2-million square kilometers. As for thickness, one article states that the Siberian eruption produced enough lava to cover the entire U.K. in about 12 kilometers of basalt (a common volcanic rock) – holy hole in a donut, Batman! In contrast, the Hawaiian volcano of Mauna Loa (considered the largest active volcano on our planet) ‘only’ has a surface area of about 5-thousand square kilometers and a thickness of about 15-17 kilometers. While that may sound like roughly 80% of the mass of all the Hawaiian islands combined (because, in fact, it is), it’s potatoes compared to Siberia.

Photo: Eruption at Mauna Loa Volcano, Hawaii. Date unknown.

Next up: Spotlight: plate tectonics and the recent Chilean and Haitian earthquakes.

Au revoir, my friends!


  1. The Mauna Loa eruption photo looks like the 1949 cone if it is M Loa. I hike this area every now and then. The southwest area of the main caldera. Don't know of any other eruption of that magnitude since then in the caldera. Having a large fountain vs a curtain of fire like in 1984. There was an eruption event in the same area around 1975 too. It was a one day fissure event.

    Start Date: 1949 Jan 6 Stop Date: 1949 May 31
    Dating Technique: Historical Records
    Volcanic Explosivity Index (VEI): 0
    Lava Volume: 1.2 x 108 m3
    Area of Activity: Mokuaweoweo and SW rift zone

    Eruptive Characteristics:
    Central vent eruption
    Radial fissure eruption
    Explosive eruption
    Lava flow(s)

  2. Thanks for answering my question! That's a load off of my mind.. =]