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this page Book Review: Canada Rocks - The Geologic Journey written by Nick Eyles and Andrew Miall (2007) Fitzhenry & Whiteside 512pp $60 By Claudia Cochrane, P.Geo., Communication Committee Member Somebody once proposed that every geologist should have a world list of must-see outcrops to visit similar to bird-watcher's life lists. If so, Canada Rocks - The Geologic Journey would be a good place to start that list. For this is Canada's story, built up rock by rock and terrane by terrane, over billions of years. A significant number of the rocks revealed at these sites are exotic slabs of real-estate acquired from foreign continents and oceans the world over.
The authors have scouted our country from coast to coast to find the outcrops that best depict their account of these events, and then have applied the most up-to-date geological and geophysical research to explain their origins. Consider if you will this sampling from the book: . the Acasta Gneiss in the Northwest Territories - at a little over 4 billion years of age, it is the oldest rock on the planet; . the crater formed by a meteorite which hit Sudbury 1.8 billion years ago; . pillow lavas in Newfoundland, resulting from extrusions of lava on the floor of the ancient Iapetus Ocean; . carbonate-capped sandstone hoodoos, which resemble giant Walt Disney mushrooms, overlooking the Red Deer Valley near Drumheller, Alberta; . diamonds from northern Canada created in former deep mantle 'hot spots'; . fossil tree stumps of Carboniferous age still standing in the Joggins Coal Beds Formation of Nova Scotia; and, . (in a note of whimsy) the beautiful Tyndall Stone from Manitoba, illustrated with a picture of an amused Queen Elizabeth standing in front of one such building block, her patterned dress blending in perfectly with the mottled bioturbated sediments of the carbonate rock. It is thought-provoking to observe how events such as tectonic activity or sea level change in one part of the country will affect the landscape of another, bearing in mind that this is a big land. Orogenies on the East Coast have influenced sedimentation in Southwestern Ontario and likewise in the west between the Rocky Mountains and the Prairies. The break-up of Pangea, and the opening of the Atlantic Ocean during the Cretaceous caused the intrusion of syenite and gabbro bodies into the Ordovician country rock of Quebec, resulting in the Monteregian Hills and their attendant marble and gemstones. Another consequence of this event continues to the present day, in the form of earthquake activity in the Ottawa-St. Lawrence system. And this vast land has been well-populated with wild life throughout the eons, whose appearance has taken many forms such as: . the very early Cambrian Ediacaran soft-bodied fauna found on the Avalon Peninsula; . the bizarre invertebrates of the Cambrian Burgess Shale outcropping in British Columbia; . the Devonian coral reefs which occupied the gentle shelf seas and are now the source of some of Alberta's oil riches; and later, . the bones of dinosaurs which roamed the Mesozoic shoreline in Alberta and Saskatchewan. An important outcrop of the K/T boundary clay is located in Frenchman Valley in southern Saskatchewan which is one of the examples that is cited to support the theory that the dinosaurs were ultimately wiped out by a meteorite.  The only thing that is missing from this compendium is a decent highway map to help us locate the sites. Perhaps the reason is because Canada Rocks is not just a catalogue of sites but an armchair travel book of a different kind; one that not only covers the length, breadth and depth of the country but journeys through time as well.
The story starts 4.5 billion years ago (or is it 4.6? - there is some contradiction in the text on this) with the early earth, a mass of planetary debris bombarded by meteorites and whirling around the sun. The theory of plate tectonics, in a cooler more solid earth, is explained next to prepare us for the main theme of the book. For as we will see, Canada is part of the 'United Plates of America'; there are 40 different terranes in Western Canada, alone. The authors observe that..."Standing in Point Pleasant Park in Halifax you can see rocks that were once part of North Africa. Fossils in a road cut in the small town of Cache Creek, British Columbia, once lived in a sea that covered China. The Arctic regions have been attached and dismembered from Siberia probably three times." The island province of Newfoundland is made up of 4 different terranes and it is here that the deep Iapetus subduction zone and the Moho are exposed at the surface; if the Russians had been able to read this book in the 1960's, they could have saved themselves the bother and expense of trying to drill to down to it! By Chapter IV, Canada Rocks takes off on its tour of the nation, starting with the oldest rocks and ending with the youngest. The first agglomeration of plates, the Pre-Cambrian Canadian Shield, is at the centre. Some of the Shield is subsequently covered in Phanerozoic sediments to make up the Interior Platform of the continent. The Interior Platform, is in turn bounded by the peripheral orogenies to the north, east and west (the source of those sediments). All of it was eventually covered by up to three kilometres of ice sheets during the last glaciation. Onto this is drafted the activities of humans such as exploiting resources, dealing with natural disasters ( including those of their own making, such as climate change) and indulging their innate ape-like inquisitiveness with investigations of the resulting scenery. Interwoven with the geology are commentary boxes about the events and scientific ideas that were generated at some of the sites: . Charles Lyell's visit to Niagara Falls in the mid-19th century, which affected his conclusions about 'deep time'; . the heralding of the 'hydro-carbon age' by the production of oil from Oil Springs, Ontario in 1858; . Touzo Wilson and the 'Plate Tectonic Revolution'; and, . Sir William Logan, founder of the Geological Survey of Canada, after whom the major Appalachian structural feature, Logan's Line was named. The authors are field geologists and most of the sites are roadside. The purpose of the book is to reach the non-specialist, which, given the broad mandate of this publication, applies to just about everybody - geologists included. Both of them are professors and have manifestly spent much time and thought to transmitting, in a logical and orderly fashion, their understanding of this very complex subject to a general readership. To this end, they have been successful and the effort they have expended is Canada's gain. The sites, are clearly and concisely explained and then illustrated with a combination of photographs and elegantly-conceived diagrams. The visual effect is further enhanced by lavish 2-page spreads of photos generated by the authors, as well as paintings, some by the famous Canadian Group-of-Seven landscape artists, and others by the French-Canadian science-fiction illustrator, Jean-Pierre Normand. And this brings us to the subject of layout and editing and the only overt criticism of Canada Rocks. It is a difficult book to read. This, not at all because of faulty composition, but because more attention could have been made to keep subject illustrations close to the written text so that the reader does not have to dodge temporarily irrelevant material in order to follow one train of thought to its logical conclusion. In some cases the text and the accompanying figures are 9 or 10 pages apart! For example, Figure 2.18, dealing with meteorite impacts is located on pages 42-43 and the text is not found until page 52. This leads to frustrating delay while the reader hunts for further elucidation on what was actually a very interesting point. A few figure numbers are actually wrong. It appears that the figure quoted on page 31 should be 2.8 instead of 2.78. Reference was made on page 68 to a series of sea-to-sea cross-sections labelled as Figure 3.7. This figure was out of order and located after Figure 3.13 toward the end of the chapter. This, by the way, was worth the hunt, as it is one of the most interesting diagrams in the book. Portions of some full page diagrams, such as Figure 3.14, which is a splendid summary of "Canada's Four Billion Year Journey", have been subducted into the book's binding. It is a matter of personal preference, but grouping four or six photos into one montage, makes it very difficult to decipher the subject matter of each individual photo. Separating them by narrow white margins results in greater clarity. There were just a few inconsistencies in the text, including the above-mentioned dating of the age of the earth, which could be caught by a more thorough editorial review. For example, according to the glossary, LIP's (Large Igneous Provinces) are not necessarily confined to ocean floor deposits, as noted in the commentary below Figure 2.14. And, there seemed to be uncertainty about the timing of Lyell's visit to Canada. Editorial issues notwithstanding (which in any case, can be easily corrected in the next edition), this book warrants a hard-cover version and should be on the shelf of every practicing geologist and nature enthusiast in Canada. This reviewer felt she was a better geologist after reading this book. It would create a durable reminder that "...the geologic history of the United Plates of Canada is a fitting metaphor for a nation whose rocks and peoples are all 'from some place else'. We are a vast confederation of continental crust and peoples brought together by plate tectonics and the lure and resources of the geologic landscape." For further reading about this new book read the interview with Andrew Miall by clicking the following link from the AAPG Explorer entitled "Canadian's Book Aimed at Public.". http://www.aapg.org/explorer/2007/11nov/canada_rocks.cfm |
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