William Moss wrote:
>
> Has anyone any experience using a proton magnetometer in an urban setting,
> particularly over roadbeds?
>
> We have recently used ground penetrating radar on several different sites.
> The results can be useful, but they are generally difficult to interpret
> without test trenching. We would like to supplement the ground-penetrating
> radar with other means of geophysical prospecting in zones where it is not
> feasible to do trenching, notably on high-traffic city streets. A proton
> magnetometer survey would seem to be one possibility.
>
> Please note that we have considered the question of doing core-samples, but
> we want to fully investigate the question of non-invasive testing first.
>
> We would appreciate any comments or references to the question.
>
> Thanks in advance for your help.
>
> William Moss
> Archeologue principal
> Design et patrimoine
> Hotel de Ville
> C.P. 700, Haute-Ville
> Quebec (Quebec)
> Canada G1R 4S9
> Tel. : 418-691-6869
> Fax  : 418-691-7853
> email: [log in to unmask]
Our experience with using magnetometers within the Historic Area at
Colonial Williamsburg has met with little success.  Too many buried
ferrous pipes and debris.  They also are affected by vehicles in the
vicinity of testing.  We have had better luck with resistivity and GPR.
Andrew Edwards
Dept of Archaeological Research
The Colonial Williamsburg Foundation
Williamsburg, VA