From prehistoric times to the fiery destruction of Pompeii in 79 A.D. and the more recent pyrotechnics of Mt. St. Helens, volcanic eruptions have aroused fear, inspired myths and religious worship, and prompted heated philosophical and scientific debate. Melting the Earth chronicles humankind's attempt to understand this terrifying phenomenon and provides a fascinating look at how our conception of volcanoes has changed as knowledge of the earth's internal processes has deepened over the centuries.
A practicing volcanologist and native of Iceland, where volcanoes are frequently active, Haraldur Sigurdsson considers how philosophers and scientists have attempted to answer the question: Why do volcanoes erupt? He takes us through the ideas of the ancient Greeks--who proposed that volcanoes resulted from the venting of subterranean winds--and the internal combustion theories of Roman times, and notes how thinking about volcanoes took a backward, symbolic turn with the rise of Christian conceptions of Hell, a direction that would not be reversed until the Renaissance. He chronicles the 18th-century conflict between the Neptunists, who believed that volcanic rocks originated from oceanic accretions, and the Plutonists, who argued for the existence of a molten planetary core, and traces how volcanology moved from "divine science" and "armchair geology" to empirical field study with the rise of 19th-century naturalism. Finally, Sigurdsson describes how 19th and 20th-century research in thermodynamics, petrology, geochemistry and plate tectonics contribute to the current understanding of volcanic activity.
Drawing liberally from classical sources and firsthand accounts, this chronicle is not only a colorful history of volcanology, but an engrossing chapter in the development of scientific thought.

Volcanoes are unquestionably one of the most spectacular and awe-inspiring features of the physical world. Our paradoxical fascination with them stems from their majestic beauty and powerful, sometimes deadly, destructiveness. Notwithstanding the tremendous advances in volcanology since ancient times, some of the mystery surrounding volcanic eruptions remains today. The Encyclopedia of Volcanoes summarizes our present knowledge of volcanoes; it provides a comprehensive source of information on the causes of volcanic eruptions and both the destructive and beneficial effects. The early chapters focus on the science of volcanism (melting of source rocks, ascent of magma, eruption processes, extraterrestrial volcanism, etc.). Later chapters discuss human interface with volcanoes, including the history of volcanology, geothermal energy resources, interaction with the oceans and atmosphere, health aspects of volcanism, mitigation of volcanic disasters, post-eruption ecology, and the impact of eruptions on organismal biodiversity.

During drilling in the Caribbean Sea on Leg 165 of the Ocean Drilling Program (ODP) a well-preserved record of explosive volcanic eruptions was found as ashfall layers within the deep-sea Cenozoic sediments. The ash layers define two major episodes of volcanism, one in the late Eocene, the other in mid-Miocene. Much of Central America is blanketed in thick ignimbrite sheets, which extend from southern Mexico into Costa Rica. The research presented in this book ties the Caribbean Sea tephra discovered during ODP 165 with the Cenozoic volcanic deposits in Nicaragua and Honduras. Along with this correlation, a detailed petrogenetic model is presented to explain the formation of the Central American ignimbrite province including geochemical variation along and across the paleoarc and evidence for the influence of sediment-derived fluids from the paleosubduction zone.