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| Environmental and Engineering Geoscience |  |
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1 Geology Department, Kent State University, Kent, OH 44242
There has long been a need for a book that summarizes the geology of Ohio. The good news is that this is a decent book, indispensable to anyone interested in Ohio geology, and is thus well worth its modest cost.
After a 33-page introductory section, the book breaks its coverage into four parts: first, two major sections comprising 114 pages on the western till plains and 155 pages on the eastern uplands (the Allegheny Plateau); second, two smaller sections on the Lake Erie lakeshore and the Ohio River valley (37 pages on each). This allows a logical treatment, starting with the oldest bedrock and the simpler glacial deposits, followed by younger bedrock and more complex glacial deposits. Each section has its own introductory material, and then within each section Dr. Camp provides a few pages of general treatment for a new area, a map of the area (based on a road section plus adjacent terrain), and additional descriptions of the geology along the road. The book makes extensive use of "side trips" to cover particular points of interest.
The maps are especially successful. They are bicolor maps, similar but superior to ones I have seen in earlier Roadside Geology volumes. They consist of black/white, grey, and diverse shades of brown with inlaid patterns that work amazingly well; they pack a lot of information into extremely sophisticated and attractive diagrams. Black-and-white photographs are abundant (almost two for every three pages). They are serviceable, and the non-historical ones must look quite good in original glossy prints (well framed; clearly an effort to get winter and spring photos of many outcrops before leaves cover everything up), but the publication quality is unexciting: I do not think people will ever thumb through the book and buy it on account of the photos.
Dr. Camp emphasizes old quarries and mines and the important role that industrial geology and geological resources have played in the history and development of Ohio. It is hard to imagine that another book should ever be needed on this topic.
My main criticisms of the book are not particularly fair, as they stem from what I would have liked the book to be and what books like this cannot provide. My ideal state geology book is Dorr and Eschmann's Geology of Michigan, which has highly educational, detail- and context-rich, period-based chapters in stratigraphic order, which teach amateurs much about geology in general and the state in particular and (with illustrations and text in the appendices) permit them to identify most of the minerals, rocks, and fossils that they will encounter in the state. (Baldwin on Oregon and Hintze and Stokes on Utah also come to mind.) In contrast, the Roadside Geology series suffers from some inherent difficulties that get resolved to varying degrees by different authors. First, it is hard to achieve the right level for the audience: too little background or too much detail and you have lost the lay-folk who would like to learn a little about the geology that they are driving through, but too little detail and you leave the trained geologist without enough to chew on. Second, discussions of geology organized around roads, to be read (hopefully to rather than by the driver) during a trip, necessarily involve considerable repetition of mid-level details, at the expense of additional context, synthesis, analysis, and explication. Third, the concept of the roadside guides really requires more cross-linkages than a book can provide, as the reader would benefit from being able to zoom in for additional detail, zoom out for context, or switch around for additional background on an as-needed basis. (These guides would really benefit if they could be presented via internet-based Wikipedia/hypertext media.)
To elaborate on these points, overall, the book is aimed at novices (it explains such things as water tables, till, meanders, and geodes), but it often seems more appropriate for someone who has taken introductory geology and remembered much of it. I did not notice any typographical or factual errors, but the writing is not always sensitive to potential misunderstandings by geological novices. For example, page 21 could be misread as saying that ostracoderms are present in the Cleveland shale, and on page 17, I would have preferred to read about evaporites being precipitated, rather than settling out. More significantly, readers probably will not be able to identify many rocks, fossils, or minerals (even to the level of ammonites, bryozoans, limestones, and quartz) that they do not already know, so illustrations and additional diagnostics would have been desirable. (They will just have to lug along copies of Feldmann's Fossils of Ohio and Carlson's Minerals of Ohio.) Although readers will learn a little about depositional settings (such as from reading that one unit represents a shallow sea whereas another represents a swamp), they will not learn much about interpreting depositional environments and facies sequences for themselves, which would be useful in a state that offers nothing but sedimentary strata. Teach readers how to interpret an outcrop and they are set for life, but tell them only what is in an outcrop, and you will have to explain every roadcut for the rest of the journey.
Overall, the book tends to use a bunch of words to get across a concept where a simple diagram would have been much better. General readers could have used graphical geological columns that cartoon how formations differ, plus more cross-sections, paleogeographic reconstructions (some are present), and, especially, more explanatory diagrams such as of types of mass movements, hypothesized drainage changes, genesis of natural bridges, more and better diorama reconstructions, stromatolite formation, rock shelter development, and examples of informative sedimentary structures and how they form (e.g., crossbedding). In fact, if half to two-thirds of the things that are listed in the glossary were instead cross-referenced in the text to more detailed descriptions and accompanying explanatory diagrams in various introductory sections, this book would be vastly more useful for lay readers. These need not have taken up a lot of space: many items could be covered sufficiently by such things as a diagram or two of glacial and post-glacial landscapes showing the formation of kettleholes, moraines, eskers, kames, glacially dammed lakes, and the like; a comparable diagram of a karst landscape that illustrates such features as sinking streams, sinkholes, caves, and karst springs; a diagram of facies relationships in meandering streams and on deltas; and so forth. A bunch of low-angle air photos or digital elevation models could also have been valuable from time to time: the ground-level photos depict many features, but often fail to help explain them. (However, the book does have some very helpful diagrams, such as the ones explaining the astrobleme structures at Serpent Mound and drainage changes on the Teays and Tuscarawas Rivers.)
Two associated problems are that road-by-road coverage also ensures a bit too much repetition of overly brief explanations, whereas key information is scattered around and can be hard to find, even though the book provides a reasonable glossary and index. I lost track of how many times I read through rather lame and overly brief explanations of honeycomb weathering, and there was also considerable repetition (albeit nicely done) about how lakes form in side-valleys that become blocked by massive and differential alluvial build-up when the main valley is full of outwash but the side-valleys are not. In contrast, the Bowling Green Fault is plotted on a map on page 62 that is not cross-referenced in the index nor in the various places the fault is discussed. Likewise, the far-too-brief description of the world-class soft-sediment deformation features found in the Berea and Bedford formations (such as the astounding mud diapirs, subaqueous slides, complex microfaulting, overturned beds, rolled-up strata, and soft-sediment thrust faults seen at and around Elyria, Berea, and Bedford) can only be found by reading through the book and running into it in the Uplands introduction. My recommendation is bulking up the introductory sections with more detail and diagrams, then superscripting page numbers throughout the text to provide cross-references between examples of things in the field and detailed explanations of them in the introductory sections. In particular, I ended up using a host of sticky tabs to mark some key pages (p. iv for roads, p. 10 for a statewide geological map, p. 15 for a state-wide overview of glacial deposits, p. 39 for geological columns, p. 157 for Pennsylvanian stratigraphy, and especially p. 25 for a diagram that happens to name Ohio's counties), so I think that the book could be greatly improved by a more detailed introductory section that starts with a series of statewide maps on each right-hand page, with matching explanations on the left (so that page-flipping superimposes the maps).
The book apparently reflects an unfortunate decision not to extend illustrations beyond the state's borders. Although the text describes tectonic events in the Appalachians and explains how they influence deposition in Ohio, the book would have benefited from illustrations of the entire Appalachian basin and its relationship to the Appalachians and to other Paleozoic basins and domes. A paleogeographic reconstruction and cross-section showing Upper Devonian facies across the northeastern United States would likewise have been very informative. Similarly, a simplified map of moraines and other glacial deposits from Maine to Minnesota would have helped a novice reader, and it is especially difficult for such a reader to understand the pre-Erie glacial lake deposits in northwest Ohio on the basis of a map that stops at Ohio's borders, in contrast to one that traces the moraines around the entire west end of the basin (i.e., including parts of Indiana, Michigan, and Ontario).
At a professional level, I would have preferred to see more detailed vertical sections, the coal industry's numbers for minable coal seams, the subsurface formation names used by drillers, and more specifics about depositional environments and paleogeography. It is of course impossible for a book like this to be comprehensive, but I missed treatment of world-class recumbently overturned crossbeds at Kendall Ledges northwest of Akron and of the unconformity-related paleokarst features studied in northwest Ohio by Charles Kahle. Nonetheless, I learned all sorts of fascinating details about Ohio geology, such as the now-fallen Devil's Tea Table (a demoiselle or pedestal rock at McConnelsville), the Oil City story, the New Concord meteorite field, big stromatolites at Maumee, and Ohio's sole "sea" arch.
In short, it is a much-needed book that represents a huge amount of work by the author, but it does have some shortcomings. It is an obligatory purchase that you will not regret if you are interested in Ohio geology.
REFERENCES CITED
Camp, M.J., Roadside Geology of Ohio:, 2006, Salt Lake City, UT Mountain Press. 411 ISBN 0-87842-524-1, $24.00.
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