Improving and facilitating research on collapse calderas

Abstract

Roughly circular depressions known as calderas are distinctive features in volcanic areas (see Figure 1). Current views explain a caldera as the surface expression of a magma chamber's collapsed roof after magma drains elsewhere. Although not all calderas are associated with explosive activity, most major eruptions (i.e., those with a volcanic explosivity index of 5 or higher) develop such collapse calderas. Calderas are usually associated with magmatic systems that have endured for thousands of years at least. These systems undergo periods of unrest highlighted by ground displacement, seismicity, and gas emissions. As a consequence, calderas are some of the most studied volcanic features, particularly for their possible implications for hazard assessment and mitigation. In addition, calderas can be associated with geothermal and ore resources and can affect climate through the products they emit.