I should think your best bet at least cost for defining the limits
would be a remote sensing survey. See R.R.B. von Frese (1984) and von
Frese and V.E. Noble (1984) in Historical Archaeology. We located a
number of early historic graves at the site of Ft. Ouiatenon in
central Indiana. Since Ralph von Frese is now on the physics faculty
at Ohio State, he is nearby and may be able to give you some advice on
how to proceed. He also may be able to work with you on the problem
using students from the university.
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