Volcanic Plumes (image) American Geophysical Union Share Print E-Mail Caption The figure above shows illustrations of plume shapes that would result from different types of volcanic eruptions. A weak plume (left) typically forms above small eruptions such as the April-May 2010 eruption of the Eyjafjallajökull volcano in Iceland, as shown in this NASA Earth Observatory image. A strong plume with a major umbrella cloud (right) forms during very large eruptions, such as shown in this Japanese Meteorological Agency image of the Pinatubo cloud on June 15, 1991. During superuruptions, umbrella clouds from strong plumes may push their way hundreds or thousands of kilometers upwind, according to a new study published in Geochemistry, Geophysics, Geosystems. Credit Credit: USGS Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.