Thursday, April 19, 2012

A Meteorite in the Southside?

The German Methodist Church of Jefferson City, built in 1874, stood at the corner of Broadway and West Elm, facing Broadway.

The congregation disbanded in 1918 and sold its property to member and neighbor Albert Thomas. In 1930 Thomas converted the church building into a duplex, which is still standing.

While excavating a basement beneath the church, workmen discovered a large, unusual boulder embedded in the dirt seven feet below the surface. Professor Alfred C. Burrill, curator of the Missouri State Museum in the nearby Capitol, was summoned. He thought it might be a meteorite, according to a newspaper article published the same afternoon of the discovery. He noted that it was rounded, “a feature peculiar to meteorites.”

The boulder turned out to be a huge chunk of red granite, clearly not a rock native to central Missouri. The particular granite can be traced to a source in Minnesota or the Dakotas. But how did it get from that northern location to a hill five hundred miles away in Jefferson City’s Southside?

It is much too large to have been carried in the current of the Missouri River, and besides, the hill it was found on is sixty feet above the present Missouri River. And it could not have been transported south by glaciers, because geologists maintain that the great ice caps of the past never spread south across the Missouri River in central Missouri.

Here is what likely happened. This theory also explains the existence of similar granite boulders found in the Osage River valley as far upstream as Tuscumbia.

When the thick ice caps to the north were wasting away, great quantities of water came down the Missouri River for centuries, causing it to run “bluff to bluff” like the great flood of 1993. Floating in the great mass of raging meltwater were huge chunks of glacial ice with boulders and other debris in them. Some of these ice floes got pushed into tributary valleys like Wear’s Creek and the Osage River, where they lodged in quiet water on the hillsides. The ice melted, and the boulders and debris were left behind and later buried in windblown silt, or loess.

These boulders are therefore called “ice-rafted glacial erratics.”

Originally thought to be a meteorite, that piece of Dakota granite is still there, in the hillside rock garden next to the excavated church basement where it was found. Albert Thomas had a whimsical nature, and he placed his unique boulder in the center of his rock garden, surrounded by peonies.

He cemented a German garden gnome, called a knusperhexe, to its top. For decades, the garden gnome smiled down on passersby on the sidewalk.

The boulder of granite still sits in that rock garden on Broadway but lacks its guardian gnome, and it is much reduced in size, due to chipping chunks away for family members and friends.

By the way, this wasn’t the first “meteorite” found in Jefferson City. Earlier, in October 1912, a supposed “meteor” was found where the new High Street viaduct was going up. The newspaper at the time quipped that meteorites were said to have diamonds in them, but that wasn’t the case with this one.

Copyright 2012 by Walter A. Schroeder.

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