Town of Frankfort centennial
Township tidbits, pp. 138-144 ff.
Ice Age organic material unearthed in Frankfort January 1982. Tribune-Phonograph. Not far below the surface of the Town of Frankfort fire pond is a still-recognizable layer of vegetation that may have grown several hundred thousand years ago. That estimate comes from the Wisconsin Geological and Natural History Survey in Madison, whose experts studied a sample of material discovered during the pond's excavaton and compared it to other similar material from the same glacier-de- posited formation. Robert Ballerstein, who lives just up the road from the site, was interested in the pond's creation two years ago, and was a frequent observer of the work. Excavation down to about 16 feet did not yield the spring the township had counted on, so a backhoe operator went down in that hole and dug about 25 feet deeper yet. Ballerstein noticed a black peaty-looking material coming out of that deeper excavation, and went down to look at where it was coming from. "I had never seen such black dirt. It was black as coal, and veryloose too. I got ahold of a big chunk ofit and pulled, and just about fell over backwards," Ballerstein said. The object he had yanked out of the excavation wall was abig piece of organic material, and it opened up to reveal swamp grass and cattails. "At first I thought it was abigrock, but then I sawit was some kind of plants. It wasn't alfalfa, I knew that, but I wanted to find out exactly what it was," he continued. Ballerstein, sensing a significant find, gave a sample of the stuff to a Marathon County official, who sent it to the Geologi- cal and Natural History Survey (GNHS) in Madison. The material was scrutinized by the staff and found to be consistent with material found in another neighboring glacial layer of con- siderable age. Radiocarbon dating of similar material, a GNHS official said, has yielded dates "beyond the capability of carbon-14 dating methods, so the material is certainly greater than 40,000 - 45,000 years old." The organic stuff, which is compressed and can be peeled off layer by brown layer, is a component of a soil unit known as the "Edgar Till" laid down during Ice Age times or earlier. According to John Attig of the GNHS, the word "till" refers to material deposited directly by glaciers. Geologists can deter- mine the direction of a glacier's flow, and the distance it traveled, by examining material laid down in tills. The Edgar Till, Attig explained, is special. "What that glacier laid down is different from most of the other deposits in the area. Minerals and fossils in the layer make it clear the glacier came from the Winnipeg lowlands in Canada, and came from the northwest, whereas most ofthe other glaciations in this area originated in the Superior or Michigan basins, and came from the north or northeast,: he said. The Ice Age, which the world is still experiencing, began two million years ago. Ice sheets have been advancing from the north and retreating back "as regular as clockwork," Attig said, for most of that time. During that two million years, there have been 15 to 20 continent-sized glacial events worldwide. Later ice sheets tend to obliterate evidence of earlier gla- ciers, making tougher work for scientists trying to identify characters of each flow. Erosion also wears away formations over time. Attig said the area around Abbotsford, now virtually flat, probably looked more like the Chequamegon area near Medford after the last glacier - very swampy, with bogs and broken terrain. There is conjecture, Attig continued, that the material in the Edgar Till is slightly younger than the stuff in a layer it covered, the Medford Till. That layer is from 750,000 to 2.1 million years old. "So the Edgar Till is a very old unit in Ice Age terms. It's beyond the reach of radiocarbon dating,* he stated. He said the age actually cannot be determined. It is also possible that younger organic material became covered and mixed with other layers. Of the 100 or so samples of material from the Edgar Till, fewer than half a dozen have yielded organic material like the one from the Frankfort fire pond. Most are composed of various proportions of three basic materials - sand, silt and clay. "Evidence indicates that the ice came and went, and there was time in between for organic material to accumulate," Attig said. The theory is that the advancing glacier plowed up soil and other debris and buried sections of swampland. Swiftly and completely cut off from oxygen, the vegetation did not decom- pose as it would have if exposed to air for any length of time. It became compressed in layers under further deposits of soil and is now located in the western and northwest areas of Marathon County, even underlying another glacial deposit, the Merrill Member, in the north. The material Ballerstein emerged from the hole with is one of 197 samples of the similar local samples identified by the state. According to Attig's report, "it displays considerable thickness for a glacial unit, ranging up to 25 meters (roughly 25 yards) on upland areas; more commonly the unit is 6 to 15 me- ters thick. The greatest thickness occurs at the western edge of the county and the unit thins and becomes patchy eastward." Ballerstein prefers a Biblical interpretation of the presence of the ancient vegetation. He feels it was inundated during the time of the great flood described in the Bible, which only Noah and his family survived. If ice was involved, he said, it was the submerged masses of icebergs that plowed through the water and leveled the vegetation, also pushing soil over it and sealing it from oxygen. Whatever the exact cause for the layer of organic stuff, Ballerstein is excited about it. "This is special. Where else are you going to find something that old? You can't go to Shopko and buy something like that," he stated. Ballerstein, somewhat of a student of natural history, said he has heard stories of old farmers trying to drill wells in the Frankfort area and hitting old logs and other material at around 28 feet - close to the depth at which he found the vegetation. The letter from Tom Evans of the GNHS stated that the material in the Edgar Till belongs to the early Pleistocene Age or the late Pliocene, "so this material is likely to be much older (than 45,000 years), possibly several hundred thousand years." To geologists, however, that distant past is merely a tick of the clock in the history of the earth. The Ice Age has occupied the earth for the past two million years. Dinosaurs were dominant, by contrast, 200 million years ago. There is every reason to believe, Attig continued, that an- other round of glaciation is coming. The past 700,000 years have shown a regular cycle of about 90,000 years of ice and cold, followed by 10,000 to 12,000 years of "interglacial" periods like the one we are in now. If calculations are correct, in another couple thousand years, glaciers will again be moving south. "The glaciation is based on the geometric relationships between the earth and the sun, and that is cyclical. Unless we 140
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