Empire of Shadows by George Black

Author:George Black
Language: eng
Format: epub
Publisher: St. Martin's Press

26

NINE NIGHTS WITHOUT SLEEP

August 29–September 3, 1870

How much did Doane actually know about the inner workings of volcanoes, and about the reason for the plumes of steam he saw belching from the ground? Probably very little. In 1870, no one had a clue about continental drift, that the sphere of Earth was formed by a collection of plates slipping and sliding around on a bed of plasticized rock fifty miles or more beneath the surface; or about magma chimneys and chambers, or supervolcanoes.

Doane knew a caldera when he saw one, but he had no idea that this one had been formed by the latest in a long string of major eruptions of the volcanic hot spot that now lies beneath the upper Yellowstone. The first of these occurred about 16.5 million years ago, in northern Nevada and southeastern Oregon. But since then, the North American continent has slipped steadily southwestward, and the “bow-wave” of the hot spot has moved northeast along the Snake River plain.1 It reached the Yellowstone area a little over two million years ago, since when it has erupted three times. The first of these eruptions, the so-called Huckleberry Ridge event, was probably the biggest volcanic event in the history of the planet, swallowing entire mountain ranges whole and creating the Island Park caldera, to the west of the Yellowstone Plateau. The second, the Mesa Falls eruption, happened about 700,000 years after that and left a smaller caldera on the Henry’s Fork of the Snake River. Doane had seen both of these calderas on his ride from Cheyenne to Fort Ellis a year earlier.

The view from the top of Mount Washburn was the result of the third great Yellowstone eruption, the Lava Creek Event, 640,000 years ago, a mere blip in geologic time. Lava Creek had spewed out vast volumes of magma and superheated liquid ash, vaporizing everything that lay in its path. The roof of the crater had imploded, dropping a thousand feet and leaving a smoking pit almost fifty miles wide. Yellowstone Lake was the most visible result. The plateau that stretched away between Doane and the lake, including what would later be called Hayden Valley, was the remnant of a larger original lake, smoothed out over the millennia by continuing flows of volcanic rhyolite and three successive waves of glaciation.

* * *

It’s been said that geology was the “fashionable science” in the United States in the middle decades of the nineteenth century.2 Wealthy patrons supported the work of prominent geologists like Ferdinand Vandeveer Hayden, who had tried and failed to reach the upper Yellowstone in 1860. By 1867, when Hayden traveled to Nebraska to launch the new Geological Survey of the Territories, the federal government had thrown its full weight behind the new discipline. People flocked to lectures on the subject in New York, Boston, and Philadelphia. Sophisticated Victorian homes prized display cabinets full of rocks and mineral samples.

However, science was still struggling to break free of religious dogma. When Doane was a schoolboy

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