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Ž .Journal of Volcanology and Geothermal Research 96 2000 143–144www.elsevier.comrlocaterjvolgeores
Book review
From Magma to Tephra: Modeling Physical Processes of Explosive Volcanic Eruptions, edited by ArminFreundt and Mauro Rosi. Elsevier, Amsterdam, 1998, 334 pp., US$ 135, Dfl. 285, ISBN 0-444-82959-8
Published under the Developments in Volcanol-ogy banner, this book presents a timely and informa-tive series of chapters concerning many of the majorissues in modeling and experimentation of explosivevolcanic processes. As the title suggests, the topicspresented take the reader through the life of a vol-canic fragment, from the time that it separates frommagma in a conduit to the time that it is deposited byfall, flow, or surge mechanisms onto the ground.
The book had its origins in the Short Course onthe Physics of Explosive Volcanism presented inconjunction with the General Assembly of the Inter-national Association of Volcanology and Chemistry
Ž .of the Earth’s Interior IAVCEI in January 1997 atŽPuerto Vallarta, Mexico. The editors also the short
.course organizers asked the contributors to updatethe short course notes, edited them to even out styledifferences, and produced this volume. One chapterwas added later to deal with volcanic conduit dynam-ics, a topic that was not the subject of an individualshort course presentation. The result is a readable,well-balanced group of seven chapters that present asynopsis of the important modeling and experimenta-tion advances in explosive volcanism. There is aminimum of repetition in the chapters and eachfollows from the previous in a well-ordered andlogical sequence.
Each chapter is written by a recognized authorityon the topic, and each presents both a personal viewand a wide ranging tour through the field of interest.The chapters are all review in nature, and bring thereader up to the state of understanding as of mid-1998. Contents were peer reviewed by another groupof experts in the various fields. The book’s sphere ofinterest does not include the nature of volcanic de-
posits, and although many insights into the cause ofdeposit characteristics are presented, the editors andauthors keep their sights aimed at the main theme —modeling and pertinent results of laboratory experi-ments.
Chapter 1, by Don Dingwell, treats magma de-gassing and fragmentation from the aspect of brittlefailure of magma in the conduit, especially experi-ments and theory that aid in our present understand-ing of how magma vesiculates and breaks up. Inter-nal and external influences on bubble growth thatproduce stresses which cause break-up are consid-ered, as well as analog experiments on acceleratingtwo-phase flows. The latest work with sudden de-compression experiments and a brief discussion ofnon-explosive degassing are also included. Thischapter underlines the complexities of magma frag-mentation, and the next on builds on this by addingan external source of water. Bernd Zimanowskidelves into the highly complex and poorly under-stood world of phreatomagmatic explosions in achapter based largely on the experimental work inhis laboratory at Wurzburg, Germany. He includes¨information from industrial engineering to investi-
Ž .gate the physics of molten fuel-coolant explosiveinteractions between magma and water, and givesapplications to eruptions, deposits, associated electri-cal phenomena, and volcanic hazards.
Chapter 3, by Paolo Papale, introduces the readerto the multi-phase, multi-flow regime world ofmagma rise, bubble growth, and fragmentation in thevolcanic conduit. Stressing the challenges of model-ing such highly complex phenomena, the authorpresents a grand tour of volcanic conduit dynamicsconcentrating on simulations involving viscous, gas-
0377-0273r00r$ - see front matter q 2000 Elsevier Science B.V. All rights reserved.Ž .PII: S0377-0273 99 00137-7
Book reÕiew144
rich magma. This chapter concludes with discussionof the relationship between conduit processes anderuption dynamics, and Greg Valentine elaboratesupon this issue in Chap. 4, where he gives a lucidand thorough treatise on eruption column dynamics.After laying down the principles of multiphase flowand the multifield approach adopted in his computa-tional experiments, he covers controls on column
Ž .buoyancy and collapse in the lower jet gas thrustregion. Influences on column height such as atmo-spheric moisture and wind are discussed and theinception of pyroclastic flows by fountain collapsereceives special attention. The most dynamic mani-festation of explosive eruptions, Plinian eruptioncolumns and particle fallout, are the topic of chapterfive, written by Mauro Rosi. This expands on onearea covered only briefly covered before -and it isthe only chapter that extensively introduces pyroclas-tic deposit characteristics. It ends by discussing howphysical parameters can be interpreted by the studyof pumice fall deposits.
The last two chapters, which make up almost halfof the book, give detailed discussions of the phenom-
Žena of pyroclastic flows by Armin Freundt and. Ž .Marcus Bursik and surges Ken Wohletz . The for-
mer very nicely combines deposit characteristics, therange of flow types, experimentation, and past nu-merical modeling from volcanology and sedimentol-ogy to attempt a globally applicable model of ashtransport and deposition by flows. The main vari-ables of magma volume, temperaturercomposition,
and steady or unsteady flow are considered, perhapshere in one place for the first time. Pyroclasticsurges, from historical, eruptive, deposit, and model-ing viewpoints, are described in the last chapter,centered around the concept of compressible two-phase flow of these gas-particle mixtures. Again, thisis as complete a treatment of this topic as can befound in any one source.
I am impressed at the overall standard of thereviews in this book. Those who want a timelysummary of much widely disseminated work willfind it invaluable. It will be purchased by academicand government volcanologists and advanced stu-dents, and would be a good choice for a graduate-
Žlevel class on explosive volcanism apart from its.price tag . The book is well presented, except for
some poor quality photograph reproductions in onechapter. It is a very good addition to the volcanologi-cal literature and the editors are to be commended.
From Magma to Tephra is available from thepublisher in Amsterdam or from the Elsevier Sci-ence, P.O. Box 945, Madison Square Station, NewYork, NY 10160-0757, USA.
Stephen SelfUniÕersity of Hawaii,
Hawaii Center for Volcanology,Department of Geology and Geophysics,
1680 East-West Road,Honolulu, HI 96822, USA
E-mail address: [email protected]