There’s several things I question, one is supposedly the Wisconsin river cut thru quartzite over softer sandstone and limestone, or the even the ice! Secondly why would this area sink and be covered by sedimentary rock. And it’s limited to this lens shape.
The lake is in an ancient gorge. The river flowed through it in the distant past. During the end of the last ice age the ice melted back and glacial Lake Wisconsin drained in a different direction, cutting out the Wisconsin Dells very quickly. Said ancient gorge is now filled with sand and water from the melted glaciers and the river had to change the place it drained south because the moraine deposited at the Southeast end of the lake is like 100 feet high or more. Also, the quartzite isn't over the softer sandstone, it's the other way around.
Thanks for doing this work Esther and Eric! Both your talks that i've seen in this series have been hugely informative! Great essential stuff!
Why can't we get more drill cores?
Probably funding
That opening photo is taken from the South Bluff looking North.
Why was I not aware of this until now? LOL
This video?
You mean this video?
There’s several things I question, one is supposedly the Wisconsin river cut thru quartzite over softer sandstone and limestone, or the even the ice! Secondly why would this area sink and be covered by sedimentary rock. And it’s limited to this lens shape.
The lake is in an ancient gorge. The river flowed through it in the distant past. During the end of the last ice age the ice melted back and glacial Lake Wisconsin drained in a different direction, cutting out the Wisconsin Dells very quickly. Said ancient gorge is now filled with sand and water from the melted glaciers and the river had to change the place it drained south because the moraine deposited at the Southeast end of the lake is like 100 feet high or more. Also, the quartzite isn't over the softer sandstone, it's the other way around.