Saturday, July 28, 2018


"Starting 16.5 million years ago, they say, vents in southeast Washington and northeast Oregon put out a series of flows that reached nearly to Canada and all the way to the Pacific Ocean. The flows created the Wapshilla Ridge Member of the Grande Ronde Basalt, a kilometer-thick block familiar to travelers in the Columbia Gorge and most of Eastern Washington. The researchers say it is “the largest mapped flood basalt unit on Earth.”

Volcanic peaks in the Northwest are scenic features but occasionally they become geological nightmares, as when Mt. St. Helens erupted.  "On May 18, 1980, the Mount St. Helens became the largest and most destructive volcanic eruption in U.S. history. By the end of its cycle of fire and fury, 57 people had died."  In Montana the main result was fine dust raining from the sky.  Then it became clear that the ancient floods of basalt had not reached inland as far as the east slope of the Rockies, but the air borne dust had created the gumbo so characteristic of the area.

"Gumbo" is a popular term for any soil that is largely clay, so that when it is wet it is sticky, slick, and impossible for wheels to travel through.  When it is dry, it is like concrete.  In Valier, when expanded, it swells a dozen times bigger under the houses; but when it dries out, it contracts and bends everything the other way.  Doorways in this town are likely to be rhomboids, but doors themselves stay square-cornered and thus can stick badly.  

A form of gumbo is bentonite, dropped by volcanoes millions of years ago, but not on land.  At that primal time the whole inland of the North American continent was a shallow sea and dropping the dust into water caused chemical changes.  Partly the gumbo is structured as tiny sheets or plates that slide against each other, and partly the particles carry an electrical charge that attracts them to the earth.  The advantage of gumbo is that it can hold water in drought.

In some places dinosaurs left their footprints in the gumbo mud, but in others the entire animal was mired until it died and was fossilized.  They say that gumbo was the lubricant that made it possible for slaves to push huge blocks of stone up inclined planes in order to build the pyramids.  They say that when Brother Van first exited the river steamboat in Fort Benton, by the time he crossed the riverfront road to the saloons aligned there, each foot weighed fifty pounds because of the mud sticking to them.   Until the gumbo roads on the rez were paved, whenever it rained Heart Butte, a hamlet of old folks was isolated.  And gumbo explains why Plains Indians never used wheels, but always used travois that slid behind the horses.  

Once I was driving in a dirt road when a passing shower slicked the surface.  My van slid uncontrollably into the ditch.  Luckily, I had a book to read.  When the grass dried out, I drove back onto the road and proceeded with no problem.

Besides creating soils, volcanoes throw up aerosols that are so full of dust that they shade the sun and drop temperatures so that winter freezes the rivers enough to drive vehicles on the ice and no crops get enough sun to grow.  These are world-wide events that are noted in the records of the survivors.  Eruptions are so effective that some have suggested it is a way to cool a warming planet, but who controls a volcano?

Bentonite is useful stuff for drilling for oil, which is a feature of the east slope.  It's slick to cool drills and can "set up" to plug old abandoned wells.  Today's drilling depends on frakking, which is the injection of water into wells to take the pressure high enough to drive up oil so it's accessible.  The water is mixed with chemicals and useless for any other purpose.  Sometimes it de-stabilizes the foundation rock enough to cause earthquakes.

Every change that yields enough profit for a boom is doomed to bust, sooner or later, but people don't necessarily plan what they will do afterwards, not just for income but also how to give up a home, material culture, a way of life.  There are basic lessons here:  one is that everything is connected to everything else even when there is a separation of a zillion years and a zillion miles; another is that all is process constantly changing and a human being is lucky if their place stays the same for lifetimes; and the third is that whatever humans do is controlled by the land, the air, and the water.  It's not the gods who control what we do, but rather the place. 

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