Volcanoes of North America (1992)

Volcanoes are much in the fore these days. They are hazardous and therefore newsworthy, and an evocative fountain and a splash of red flowing lava (usually of Hawaiian volcanoes) accompanies most film reports of volcanic activity. At present, Mt Redoubt in Alaska produces gas and ash emissions, and seismologists are monitoring it closely because any escalation of events could lead to major eruption, and that might spell disaster t o the oil facility down the Drift River at Cook Inlet. Eruption could be on the scale of Mt St FIelens in 1980, since it is also an ice-capped basalt-dacite stratovolcano. The world must therefore be kept informed. The Global Volcanic Network, organized by the Smithsonian Institution of Washington, DC. publishes a monthly bulletin of events. For more rapid dissemination, volcanologists as well as the emergency services are linked by an electronic mail network which gives details and the current ‘state of alert’ of eruption. For many, the attraction of volcanoes is their majesty and power, often set in areas of great scenic grandeur with wild rivers and lush forests. In North America, visting volcanoes is facilitated by the commendable policy of National Parks, with their camping grounds and trails. The wide interest shown by US and Canadian visitors must, a t least in part, be credited to these facilities. This book encourages such interest further by presenting good, in-depth information in a clear format. Wood and Kienle are to be congratulated on the way they reduced the contributions from 81 US and Canadian scientists into this easily consulted volume. It is nearly 100 years since the first and only detailed account of North American volcanoes was published; that was by Israel Russell in 1897. He missed many, and even this new book admits omitting a few small volcanic fields about which little is known. Apart from these few, it is a comprehensive record all the North American active and dormant volcanoes, and in fact seems to include any structure that is recognizably volcanic, some even as old as Miocene, although five million years is stated on p. 2 to be the age limit. Where to draw the line is always the bane of writers. In this case, Fhould small satellite vents be separately listed? The authors follow the truism that no volcano is a single vent, but is a collection of vents, sometimes clustered on or around a single stratovolcano such as Mt Garibaldi in British Columbia (p. 144), or sometimes spread over many miles such as the 52 vents and 65 flows covering 150 km’ of the Cima volcanic field in the Mojave desert of California (p, 240). The book follows the volcanic arc pattern of volcanoes, beginning in the northwest and working eastward and southward. Thus the book begins in the Aleutian Islands, then passes through Alaska, western Canada, western USA, ending in New Mexico, apart from the Hawaiian Islands which is tacked on at the end. The text is split into three parts: the volcanic structures of Alaska (100 pages); of Canada (36 pages); and of the western United States (200 pages) of which the last 33 pages are devoted to Hawaii. To my mind, it would have been better if Hawaii were considered as a separate and fourth part. Each part, and the Hawaiian section, is introduced by a clear summary of the plate tectonic or other reason for the presence of the volcanoes, relating them to subduction or hotspots as appropriate, and giving a short but up-to-date account of the mantle or other source of the magmas, how magmas progress through chambers in the crust, and how chemical variation seen in the lavas might occur. The emphasis on the volcanic structures of western USA rightly reflects the greater knowledge as well as the considerable public interest, combined with ease of access, of these volcanoes. Over 250 volcanoes and volcanic fields are listed in this book. Each is systematically described, beginning with a clear listing of name, general locality, type of structure, latitude and longitude, elevation, area o r island size, caldera depth, volcano and/or caldera diameter, eruptive history and petrological character. This enables quick retrieval of the essential information about each volcano. Key maps are given for each part and are most useful, the index is the minimum necessary, and the list of contents would become useful if the page number for each volcano were listed there instead of being buried state by state within the book. The next half dozen paragraphs describe the morphology of the volcanic structure, the distribution and accessibility of craters and lavas, and give a potted volcanological history of what happened where. Then comes the all important section of ‘how to get there’. usually condensed to five lines of ‘drive x km along highway y, stop at landmark z and then hike along the trails a, b and c’, or ‘x minutes float-plane ride to y, and then walk’. Cautionary remarks such as those for getting to Mt Redoubt are useful: you can’t land your helicopter in the National Park except with a permit from the park superintendent. Many others have access only at weekends. Finally references are given, usually two that tell you where to look for further detail. Useful 1:250000 scale maps accompany nearly all descriptions, and well-angled photographs accompany most. The authors hope the book will become the standard reference of North American volcanoes to be used by volcanologists, petrologists, geochemists and geographers. It should. I think it will also appeal to any inquisitively minded, ‘green’ person, since only a few parts of the text, particularly those in the introductions, embody professional terminology. I am glad to see that the authors use the most up-to-date nomenclature when naming rock types. The book is too bulky ( 2 9 0 ~ 2 2 O x 3 0 m m ) and too weighty (1.4 kg) to be a handbook, although it would be useful to have it in the field during visits. The binding is tough. The printing is in double column page layout, the print style is clear and the individual sections are instantly made evident by use of different founts; full marks for clarity. Nearly full marks for the scarcity of errors, but one glaring one which escaped detection is in the titling on p. 315 where Hawaii is apparently in Alaska.