Mornin all!
Antiqua:
It makes one wonder what the archies found to do a dig there....
Here in the great lakes area and to the North , were feasts of the dead. I'm guessing from memory it was the Ottawa nation here. (But let's not trust my memory too much..) When stored remains would be interred en masse at certain intervals.
Part of ceremonies involved grave goods interred with them. Perhaps that was the interest? IF the low area was a large dug communal grave originally.
This link suggests relocating previously stored remains when a village was moved. The old accounts I read years back detailed the cleaning of bones and their being kept in lodges till interment. No mention of relocating them after the intermittent ceremonial mass internment.
Could be era , or a given nation's traditions , or mixed information .....
If the depression is natural , perhaps it was used as a fortification ,shelter, or wind break.
One South of me with an interesting tie to relics farther North was termed an earthwork , but was really just a single vertical log wall with a ditch on one side.
The ditch was removed earth to strengthen the wall base , but also the refuse pit.
One may speculate why the wall was desired. From attracting smoke to travel up, and to reflect heat. To a visual screen. To a defensive structure/cover. To a wind break. Ect..
Of note , as with many sites it was where/near two rivers converging. Alas , I no longer recall how far from water.
During threat of assault , I could see backing off travel/waterways to be out of sight ,hearing, smell..
And in times of peace /security , being with water at /near hand.
https://en.wikipedia.org/wiki/The_Huron_Feast_of_the_Dead