Review by Christy Bulkeley
Geology – August 2005 – Colorado Central Magazine
Earth: An Intimate History
By Richard Fortey
Published in 2004 by Alfred A. Knopf
ISBN 0-375-40626-3
RICHARD FORTEY’S STUNNING Earth: An Intimate History sweeps through not only the ages of the earth but also the evolution and politics of the sciences studying the earth. He also explores how the earth’s surface affects people and how people use it. Fortey, a paleontologist at the Natural History Museum in London, set out to “explain the character of the earth….(and) to explore the influence of geology on the character of landscape and the character of people.”
Indeed, “the rocks beneath us are like an unconscious mind beneath the face of the earth,” he says. Fortey offers huge amounts of information — from field studies and laboratory experiments to the human nature of those who have documented key theories of earth’s evolution.
Descriptions of locations where the drama of earth’s story remain visible anchor the book. Fortey takes the reader on journeys through the locales, telling how variations in the earth’s visible layers and features figured into scientific thought about the evolution of the earth and developed into the dominant theory of plate tectonics.
Fortey comes close to Central Colorado when he travels the basins and ranges to the west. He describes the eras seen from mule back on the trail into the Grand Canyon; cites the uplifting of the Colorado Plateau (as the Pacific tectonic Plate pushed under the North American Plate); acknowledges the Rocky Mountains as the oldest Western U.S. range resulting from repeated land-mass collisions; refers to an article co-authored by Kristy Tiampo of the University of Colorado’s Cooperative Institute for Research in Environmental Sciences (predicting an earthquake before it happened thanks to advances in the sciences).
Fortey also describes the birth and life of particular elements:
“Silver and gold are unusual in occurring in nature as the pure element. Few other elements other than gases occur in such an unadulterated condition…Copper also occurs in sheets and nuggets, often so distinctively shaped they seem to have been beaten out by an earth sprite with an eye for abstract sculpture.” Later, Fortey discusses experiments underway to figure out how particles of gold accumulate and aggregate into nuggets.
“Common elements make proletarian marriages…This does not mean that a common mineral cannot be uncommonly beautiful. Perfect quartz crystals (in) its more massive form, rock crystal, has a kind of vivid transparency that makes most glass look insipid…”
“The fiercest, strangest, least tractable features on the face of the earth belong to granite.” Competing theories of the formation and movement of granite occupied part of the last century and contribute to the human story; our understanding of granite has been advanced by answers made possible with improved laboratory equipment and continues still.
Although the scope of Fortey’s work precludes the kind of regional attention that readers expect to find in Colorado Central, detail upon detail reported from elsewhere feed into new ways of seeing, thinking about, questioning and understanding what’s all around us.
This multi-layered story lives up to Fortey’s description of the book as an anti-textbook. The narrative adds information, theories, evidence, and conclusions in much the same way that knowledge and thought developed over several hundred years. Thus the book doesn’t work as a reference (and wasn’t intended to); readers can’t turn to one or two places to find everything.
Fortey’s narrative opens at the Bay of Naples “where the science of geology started.” A crypt along the way serves as a “reminder of the third great class of rocks besides those of sedimentary and igneous origin. These are metamorphic rocks. They may have started out as either of the other two categories, but have been altered–or even completely transformed–by heat, pressure or by any combination of the two, when caught in the great mill of mountain-building within the depths of the earth.” That particular discussion then turns to marble (“which started as humble limestone…(and)…can appear to resemble anything from blue cheese to slices of liver, or they can be pure white…”).
Elsewhere, describing what happens when two land masses collide, Fortey says:
“The rocks themselves transform. This is because dramatic thickening also entails burial and burial means that the ambient pressure on the rock increases–as does the temperature…Minerals change from one to another; the very fabric of the rock is altered. The original rock becomes disguised and eventually unrecognizable. If the rocks were once sedimentary, any fossils they may have formerly contained become obliterated.”
Advancing technology adds to the story–enabling measurements of magnetic markers left in some minerals, which demonstrate where the magnetic poles were when the minerals were formed. The most common is a simple iron oxide called magnetite. Again, improved laboratory instruments have made the mapping of magnetic pole movement possible, which, in turn, has helped trace the movement of continents.
Other technological advances also enrich the story and understanding: Radiometric dating; X-rays that can discover the structure of crystals at the atomic level; lasers with which tiny amounts of a mineral can be punched out; and more.
Most of this story is probably known to geologists and other scientists whose work relates to earth’s evolution, and to those whose vocations or avocations tie in directly–say crystal and fossil hunters. Fortey writes for the rest of us, those of us who find ourselves living in dramatic, puzzling landscapes which provoke questions and curiosity.
Although Fortey carefully defined many technical terms in the narrative, a glossary would have helped. So would an index of technical drawings. I’d have given up at least some of the 32 pages of color photographs for such quick reference aids. But the author mostly succeeds in making earth’s story coherent and accessible. Though he illuminates the earth’s history by examining other places, much of what he describes is familiar, paralleling our own part of the world and making learning immediately relevant.
–Christy C. Bulkeley
Bulkeley, a former newspaper reporter, editor and publisher, lives in North Carolina and rides around Central and Southern Colorado with her Denver-based brother and sister-in-law, Peter Bulkeley and Edie Conklin.