Reading Rocks

By R.Z. Sheppard

IN SUSPECT TERRAIN by John McPhee

Farrar, Straus & Giroux: 210 pages; $12.95

No other journalist avoids the obvious with as much success as John McPhee. To hold readers through books about oranges, the New Jersey Pine Barrens or birchbark canoes is a tribute to his eye for narrative grain and hand for prose dovetails. The sanding and finishing are done by editors at The New Yorker, where McPhee's books first appear.

In Suspect Terrain, the latest issue of this arrangement, is a companion volume to Basin and Range (1981). That book explained the New Geology, based on McPhee's travels through the far West with a proponent of plate tectonics. This branch of earth science grows from the theory that the planet's great land masses slide around like dishes on a boat. Over time, Africa could end up in Brazil's feijoada, Australia in China's egg foo yung.

Hot stuff but overrated, says Anita Harris, the geologist who guides McPhee through gaps, folds and sediment from Brooklyn to the dunes of northern Indiana. Harris reads old rock, both high and low, and she is not convinced that plate tectonics adequately explains a great deal of "suspect terrain." The whys and wheres of her disclaimers may not rivet the attention of readers whose geology begins on the front lawn and ends at the beach. But Harris' rigors of body and mind cannot fail to impress. She moves robustly over the landscape lugging her hammers and rock samples. She computes the hard evidence of a canyon wall or handful of dirt with quick confidence and cheerful clarity. "I see little pieces of carbon. I see green chert. I see a bug crawling through the sand."

McPhee succeeds beyond expectation in revealing character in the disciplines of work. He, too, is very busy backing and filling to present a story that spans 4.6 billion years. Beginnings and middles can get lost in this world without end. Geology, which never tires of repeating itself, is oblivious to the need for plot and moral. Despite quakes and eruptions, the earth is agonizingly incremental, and McPhee must use all his skills to extract its story. On the reluctant process of diamond formation: "They want to be graphite, and with a relatively modest boost of heat graphite is what they would become, if atmospheric oxygen did not incinerate them first. They are, in this sense, unstable--these finger-flashing symbols of the eternity of vows, yearning to become fresh pencil lead." Noting that the last Ice Age stopped around Ebbets Field, vanished home of the Brooklyn Dodgers, he writes: "When a long-ball hitter hit a long ball, it would land on Bedford Avenue and bounce down the morainal front to roll toward Coney on the outwash plain. No one in Los Angeles would ever hit a homer like that."

Usually McPhee expands on a small subject. Geology presents the opposite problem: condensing events that might or might not have happened during incomprehensible periods of time. Still, in his 210-page book, he does what no other writer has done. For an hour and a half, he makes the earth move. --By R.Z. Sheppard This file is automatically generated by a robot program, so viewer discretion is required.