Once were glaciers. There still are, for now, just not this low, not this south. But their tracks reach halfway down from the pole, evidence of past sprawl.
For a long time, "glacial" has meant slow. A glacial pace excruciates and frustrates, witholds fruition until long after you've lost interest. To some it's majestic, stately, an inspiring slow march across ages.
Of course we know that to be bullshit now, and although the concept of glaciers as slow may hang on among english majors and other metaphor junkies, scientists who've studied this kind of earth artistry now know just how fast a glacier can move. In our warmed atmosphere, they can break up quickly, mile after mile of what appeared to be a solid block of ice fracturing, sliding, turning into mush in a single summer. Beneath their stoic mantles, river rush and rage. And in the cores that remain solid (for now), strata of long-fallen snow tell about sudden onsets of ice ages, rapid accumulations, quick thaws.
Here in the northwest, especially in the sere interior, areas bare of towering forests and other rock-swallowing greenery, geology speaks of other glacial speed. Glaciers here once held enormous lakes, icy fastness damming inland seas. As the climate warmed, water sought the weak points, runnning off the top, tunneling through cracks and voids, shimmying beneath, pioneering trickles searching for opening to turn the vast potential energy of the impounded water kinetic and free. Lake Missoula, about 200 miles long and holding something like 500 cubic miles of water, let rip and carved out the canyons we call coulees. Rock formations downstream held back water for a time, but the lake drained in a couple of days, and rock cannot hold up to that forever, a couple hundred square kilometers of it gave way, turning the once broad expanses of the laval plateau into a tracery of coulees grand and miniscule.
The floods happened when people were still a new and naturalizing species in the new world. I can see them, living in a good spot along the river, enjoying the bounty of an unspoiled landscape, and then feeling the earth shake, hearing a roar, and then being wiped out by a wall of water. Throughout the Columbia watershed, the best human habitat was ripped apart. The archaeologist in me weeps not just for the people who were swept away, crushed by boulders, and drowned, but also for the earliest sites, obliterated. (Of course, there must also be some sites, located in a lucky lee or a high bench that only got a blanket of sand and silt, where entire Pleistocene camps must have been buried intact.)
But once the ice sheets ceded the lower latitudes and no ice dams held more potential cataclysms, the coulees remained. Over time, the interior dried out, and the canyons became oases, protecting streams and ponds from wind and sun, collecting mountain snowmelt, thunderstorm runoff, percolating rain of yore.
Above, scabland lava, sagebrush, fields of glacial till. Deer instead of mastodons, solitary sage grouse instead of sky-darkening flights of fowl. Beautiful in its way, and far short of desolation, but plenty of dessication to go around. People traversed this country, hunted some, found patches of roots to eat, but it was sunburnt and windswept.
Far better to retreat to the protection of a coulee. Here there was water, and waterfowl, and all the critters who come to drink...and feed the people. Here grew moisture loving plants that could not survive up top: food, medicine, fiber, mats, and so many materials vital to the organic age. Here was escape from the relentless wind, a place where fire can be tamed and live in a hearth and that had more wood to burn in the first place. Here, flood-ripped canyon walls exposed tool rock, flood deposits made easy picking for cooking and sweatlodge rocks. Here, labyrinths well known to locals afforded escape from marauders, ambushes for hunting, secret and secluded spots for communing with the spirits. The great coulees, Grand and Moses and others, became highways as bipeds grew in number and eventually reintroduced horses.
Cool. Ease.
For a long time, "glacial" has meant slow. A glacial pace excruciates and frustrates, witholds fruition until long after you've lost interest. To some it's majestic, stately, an inspiring slow march across ages.
Of course we know that to be bullshit now, and although the concept of glaciers as slow may hang on among english majors and other metaphor junkies, scientists who've studied this kind of earth artistry now know just how fast a glacier can move. In our warmed atmosphere, they can break up quickly, mile after mile of what appeared to be a solid block of ice fracturing, sliding, turning into mush in a single summer. Beneath their stoic mantles, river rush and rage. And in the cores that remain solid (for now), strata of long-fallen snow tell about sudden onsets of ice ages, rapid accumulations, quick thaws.
Here in the northwest, especially in the sere interior, areas bare of towering forests and other rock-swallowing greenery, geology speaks of other glacial speed. Glaciers here once held enormous lakes, icy fastness damming inland seas. As the climate warmed, water sought the weak points, runnning off the top, tunneling through cracks and voids, shimmying beneath, pioneering trickles searching for opening to turn the vast potential energy of the impounded water kinetic and free. Lake Missoula, about 200 miles long and holding something like 500 cubic miles of water, let rip and carved out the canyons we call coulees. Rock formations downstream held back water for a time, but the lake drained in a couple of days, and rock cannot hold up to that forever, a couple hundred square kilometers of it gave way, turning the once broad expanses of the laval plateau into a tracery of coulees grand and miniscule.
The floods happened when people were still a new and naturalizing species in the new world. I can see them, living in a good spot along the river, enjoying the bounty of an unspoiled landscape, and then feeling the earth shake, hearing a roar, and then being wiped out by a wall of water. Throughout the Columbia watershed, the best human habitat was ripped apart. The archaeologist in me weeps not just for the people who were swept away, crushed by boulders, and drowned, but also for the earliest sites, obliterated. (Of course, there must also be some sites, located in a lucky lee or a high bench that only got a blanket of sand and silt, where entire Pleistocene camps must have been buried intact.)
But once the ice sheets ceded the lower latitudes and no ice dams held more potential cataclysms, the coulees remained. Over time, the interior dried out, and the canyons became oases, protecting streams and ponds from wind and sun, collecting mountain snowmelt, thunderstorm runoff, percolating rain of yore.
Above, scabland lava, sagebrush, fields of glacial till. Deer instead of mastodons, solitary sage grouse instead of sky-darkening flights of fowl. Beautiful in its way, and far short of desolation, but plenty of dessication to go around. People traversed this country, hunted some, found patches of roots to eat, but it was sunburnt and windswept.
Far better to retreat to the protection of a coulee. Here there was water, and waterfowl, and all the critters who come to drink...and feed the people. Here grew moisture loving plants that could not survive up top: food, medicine, fiber, mats, and so many materials vital to the organic age. Here was escape from the relentless wind, a place where fire can be tamed and live in a hearth and that had more wood to burn in the first place. Here, flood-ripped canyon walls exposed tool rock, flood deposits made easy picking for cooking and sweatlodge rocks. Here, labyrinths well known to locals afforded escape from marauders, ambushes for hunting, secret and secluded spots for communing with the spirits. The great coulees, Grand and Moses and others, became highways as bipeds grew in number and eventually reintroduced horses.
Cool. Ease.
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