Prehistoric American Indian settlement discovered in Ohio

The earliest suggestion of something worth uncovering on thias plateau above the Huron River (Ohio, USA) were some dark electronic smudges on a piece of graph paper. The smudges piqued Brian Redmond's professional curiosity, though. They were a kind of map of the field's subsurface, traced by an instrument called a fluxgate gradiometer. Sweeping one a few inches above the ground produces a sort of magnetic fingerprint of subsurface soil that's been disturbed in some way, whether by digging or burning. The patterns that the Cleveland Museum of Natural History's archaeology curator saw on the graph paper looked like the signatures of a large-scale ancient dwelling. The dots could be cooking or trash pits, the parallel lines a couple of filled-in ditches, and the oval possibly the remnants of a stockade.