Hi Ksk, yes, the glaciers were the final act. They bulldozed out the great lakes, carved out river valleys, piled up mountainous moraines and spread tons of fine fertile dust across the land.😊
Could the arches also correspond to divides? Because in the case of the Kankakee Arch it seems all the rivers north of it flow into Lake Michigan and the rivers south of it flow into the Mississippi/Ohio watershed.
Great question Therese, My take is the rivers became established when the arch ( anticline) was in fact a ridge. As the ridge eroded, rivers cut down into it and maintained their orientation through time😊
Hi T, Took a second look at the Kankakee Arc, and you are quite right. It IS a structural high. Im gonna do more geo- digging and then do an “ addendum “ video. Thanks for your observation!😊
@@PapaRocks Thanks! I'm not sure about the other two as I haven't done as much traveling in those areas but I am very familiar with the landscape of northwestern Indiana and southwestern Michigan. There is an east-west road paralleling the Borman Expressway (I-80/94) to the south called Ridge Road (the original routing of US 6) and I think you will find your structural high there. I wouldn't be surprised to learn Ridge Road was based on a Native American trail as the surrounding lowlands were/are quite swampy (the Borman in particular is prone to flooding which makes it even more of a nightmare to navigate). As for Nashville being in a basin, that was something I also noticed on my travels through that part of Tennessee. You have to climb down into it and then climb back out. If you want to see an example of an ancient rift valley, the Sequatchie Valley west of Nashville is an excellent example.
@@theresemalmberg955I grew up in Hammond (54 thru 77). Ridge Road was the former lakeshore of Lake Michigan. Route 30 ran along the big moraine left by the last glacier. The main E-W roads south of Ridge Road also ran along former lake shores. The land between Ridge Rd. and 165th St. was a bottom land drained by the Little Calumet River. North of 165th was the start of wooded sand dunes and sloughs. The Cook County Forest Preserves are the remaining woods and swamps / peat bogs that were present when the first settlers arrived. The settlers and stage coaches used the same E-W paths on high dry grounds as the natives did. There's one that starts at State Line just north of 165th called Michigan City Road that runs NW thru Cook County. That once connected to 165th to take East to reach Michigan City. The Kankakee Arch outcrops in Thornton where I-80 crosses over the big limestone rock quarry. Around 50 miles to the SE south of the Kankakee River there is a meteor impact dome called the Kentland Crater. There you can the rock strata that makes up the Kankakee Arch standing vertical inside a rock quarry. That strata is 2000 feet underground except where it shot up after being forced down by a meteor. All traces of the crater have been removed by erosion and glaciers. They figure around 900+ feet of the dome also has been removed by both.
I will definitely have to watch this several more times and locate an appropriate geology book. I live in southwest Ohio just east of the Great Miami River. At this late stage of my life I am constantly wondering about the land beneath my feet. Strange. Thank you for the video Papa! 👍👍!!!