Reference Work Entry

Encyclopedia of Complexity and Systems Science

pp 9763-9784

Volcanic Eruptions: Cyclicity During Lava Dome Growth

  • Oleg MelnikAffiliated withInstitute of Mechanics, Moscow State UniversityEarth Science Department, University of Bristol
  • , R. Stephen J. SparksAffiliated withEarth Science Department, University of Bristol
  • , Antonio CostaAffiliated withEarth Science Department, University of BristolIstituto Nazionale di Geofisica e Vulcanologia
  • , Alexei A. BarminAffiliated withInstitute of Mechanics, Moscow State University

Definition of the Subject

We consider the process of slow extrusion of very viscous magma that forms lava domes. Dome‐building eruptions are commonly associated with hazardous phenomena, including pyroclastic flows generated by dome collapses, explosive eruptions and volcanic blasts. These eruptions commonly display fairly regular alternations between periods of high and low or no activity with time scales from hours to years. Usually hazardous phenomena are associated with periods of high magma discharge rate, thus, understanding the causes of pulsatory activity during extrusive eruptions is an important step towards forecasting volcanic behavior, especially the transition to explosive activity when magma discharge rate increases by a few orders of magnitude. In recent years the risks have increased because the population density in the vicinity of many active volcanoes has increased.

Introduction

Many volcanic eruptions involve the formation of lava domes, which are extrusions ...

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